|
|
Walter Schirra
Pictured is astronaut Walter
11/19/07
| Description |
Pictured is astronaut Walter M. Schirra, one of the original seven astronauts for Mercury Project selected by NASA on April 27, 1959. Schirra's Mercury-Atlas 8 mission, during which he piloted his Sigma 7 spacecraft, was the third manned orbital flight by the United States. Image credit: NASA |
| Date |
11/19/07 |
|
Titan (T16) Viewed by Cassin
| Description |
Titan (T16) Viewed by Cassini's Radar July 22, 2006 |
| Full Description |
This radar image shows the entire scene in which hydrocarbon lakes were first discovered on Titan, near its north pole (see Lakes on Titan). This image was acquired on July 22, 2006, by Cassini's radar instrument in synthetic aperture mode. The most striking landforms are the lakes: dark patches, some circular, some irregular, many with apparently steep rims, over much of the terrain north of 70 degrees latitude. The most convincing lake forms occur at the narrowest, central part of the scene, which is at the highest latitudes. Here they have short, stubby channels leading into them, and brighter areas within that indicate either dried-up lakes or that we are seeing through a transparent liquid. The image also shows the considerable variation in the kinds of surface features found at different latitudes. Beginning at the left (20 degrees north by 142 degrees west) and heading north, a circular feature about 75 kilometers (47 miles) in diameter is seen, which could be either an impact crater or a volcanic caldera. Other less distinct circular forms are seen next, possibly including some dried lakes, followed by some ridge-like terrain with dark meandering channels or valleys. The dark lakes begin to appear next (at about 70 degrees north), with more distinct lakes in the middle of the scene, where the swath is closest to the pole and starts to descend to the south. Farther on, apparently dry lakes and canyons begin to dominate, and the region becomes more complex and etched. At the extreme right end, dunes similar to those seen previously mingle with brighter features. The swath ends at 13 degrees north by 347 degrees west. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL |
| Date |
January 11, 2007 |
|
Liquid Lakes on Titan
| Description |
Liquid Lakes on Titan |
| Full Description |
The existence of oceans or lakes of liquid methane on Saturn's moon Titan was predicted more than 20 years ago. But with a dense haze preventing a closer look it has not been possible to confirm their presence. Until the Cassini flyby of July 22, 2006, that is. Radar imaging data from the flyby, published this week in the journal Nature, provide convincing evidence for large bodies of liquid. This image, used on the journal's cover, gives a taste of what Cassini saw. Intensity in this colorized image is proportional to how much radar brightness is returned, or more specifically, the logarithm of the radar backscatter cross-section. The colors are not a representation of what the human eye would see. The lakes, darker than the surrounding terrain, are emphasized here by tinting regions of low backscatter in blue. Radar-brighter regions are shown in tan. The strip of radar imagery is foreshortened to simulate an oblique view of the highest latitude region, seen from a point to its west. This radar image was acquired by the Cassini radar instrument in synthetic aperture mode on July 22, 2006. The image is centered near 80 degrees north, 35 degrees west and is about 140 kilometers (84 miles) across. Smallest details in this image are about 500 meters (1,640 feet) across. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm . Credit: NASA/JPL/USGS |
| Date |
January 3, 2007 |
|
Two Sides of Dunes
| Description |
Two Sides of Dunes |
| Full Description |
This pair of images, taken by the Cassini spacecraft radar mapper on two different Titan passes on Dec. 11, 2006 (T21 left), and Oct. 29, 2005 (T8 right), represent two different views of a field of dunes located near 9.4 degrees south latitude by 290 degrees west longitude. The images were taken in synthetic aperture mode and have a resolution of approximately 500 meters (1,640 feet). North is toward the top of both images, and each image is approximately 400 kilometers (250 miles) long by 275 kilometers (170 miles) wide. The images are different only because the radar instrument illuminated the dunes from different directions. Acting somewhat like a flash camera, the radar sends out microwave pulses and makes an image from the pulses after they are reflected back. Imagine that both the "camera" and the "flash" come from the left in the left image and from the top in the right image. Most obvious differences are seen in the large bright feature at the center of both images. At left, its left edge is brighter, emphasizing the more steep slopes there. Farther left, the dunes are more clearly defined in the right image as their faces are caught by the illumination. However, since the dunes are visible in both images, it is likely that the materials making up the dark and light stripes are also somehow different. More detailed studies of how materials on Titan reflect and scatter at different angles are giving us clues about what different materials might be present in this cold and distant world. For more information about dunes on Titan, see Dunes Galore. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL |
| Date |
January 11, 2007 |
|
Titan Dunes over Possible Cr
| Description |
Titan Dunes over Possible Craters (T23) |
| Full Description |
This radar image of Titan's well-known dunes is distinctive because it may show an age relationship between different classes of features on the surface of this frigid world. Taken by Cassini's radar mapper on Jan. 13, 2007, during a flyby of Titan, three kinds of terrain can be seen. Throughout the image, the fine striping has been identified as dunes, possibly made from organic material and formed by wind activity. Dunes are a common landform on Titan (see Two Sides of Dunes and Swimming in Dunes). The bright material at the lower right of the image is interpreted as being topographically higher than the dunes that go around it, and several circular features seen at the top center may be craters that are slowly being buried by the dunes. Since the dunes seem to lie over the craters, the dune activity probably occurred later in time. This image was taken in synthetic aperture mode and has a resolution of approximately 350 meters (1,150 feet). North is toward the top left corner of the image, which is approximately 160 kilometers (100 miles) long by 150 kilometers (90 miles) wide. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL |
| Date |
January 24, 2007 |
|
A New Crater on Titan?
| Description |
This radar image of Titan shows a semi-circular feature that may be part of an impact crater. Very few impact craters have been seen on Titan so far, implying that the surface is young. |
| Full Description |
This radar image of Titan shows a semi-circular feature that may be part of an impact crater. Very few impact craters have been seen on Titan so far, implying that the surface is young. Each new crater identified on Titan helps scientists to constrain the age of the surface. Taken by Cassini's radar mapper on Jan. 13, 2007, during a flyby of Titan, the image swath revealed what appeared to be the northernmost half of an impact crater. This crater is roughly 180 kilometers (110 miles) wide. Only three impact craters have been identified on Titan and several others, like this one, are likely to also have been caused by impact. The bright material is interpreted to be part of the crater's ejecta blanket, and is likely topographically higher than the surrounding plains. The inner part of the crater is dark, and may represent smooth deposits that have covered the inside of the crater. This image was taken in synthetic aperture mode and has a resolution of approximately 350 meters (1,150 feet). North is toward the top left corner of the image, which is approximately 240 kilometers (150 miles) wide by 140 kilometers (90 miles) high. The image is centered at about 26.5 degrees north and 9 degrees west. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. Credit: NASA/JPL |
| Date |
February 16, 2007 |
|
Titan (T18) Viewed by Cassin
| Description |
This radar image, obtained by Cassini's radar instrument during a near-polar flyby on Sept. 23, 2006, is the second scene that shows clear shorelines reminiscent of terrestrial lakes. |
| Full Description |
This radar image, obtained by Cassini's radar instrument during a near-polar flyby on Sept. 23, 2006, is the second scene that shows clear shorelines reminiscent of terrestrial lakes. With Titan's colder temperatures and hydrocarbon-rich atmosphere, these lakes most likely contain a combination of methane and ethane (both hydrocarbons), not water. This high-latitude opportunity confirmed scientists' predictions that lakes would be present here, consistent with calculations that suggested that hydrocarbons would be stable as liquids at the colder, high latitudes. It also showed unusual complex terrain, the origin of which remains a mystery. The image is illuminated by the radar from the top, and shows features as small as about 300 meters (980 feet). Starting at the left (63 degrees north latitude by 255 degrees west longitude), where the terrain appears bland and dark, the swath heads northeast into a more rugged, mottled terrain, probably containing dried lakes and canyons formed by the presence of liquid hydrocarbons. The first lake, an irregular, almost-triangular shape about 16 kilometers (10 miles) across at the widest point, can be seen near the bottom of the image, it appears to be fed by two channels from the south. Several more lakes can be seen about one-third of the way into the swath, near the closest approach to the pole, (north of 75 degrees north latitude), including Titan's "kissing lakes," each 20 to 25 kilometers (12 to 16 miles) across. Two other lakes feature narrow or angular bays, including a broad peninsula that on Earth would be evidence that the surrounding terrain is higher and confines the liquid. Continuing on, about three-quarters of the way through the swath, the terrain becomes brighter and more rugged, again indicating possible dried lakes and canyon-like structures. A long 100-kilometer (60-mile) series of grooves appears, likely carved by liquids. Next is an area of bright terrain with an unusual directional texture, indicating possible dunes, but brighter and perhaps different in nature than those seen elsewhere. Finally, towards the end of the swath, where the image quality is poorest, the terrain becomes mottled and difficult to interpret. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. Credit:NASA/JPL |
| Date |
February 20, 2007 |
|
Titan: Larger and Larger Lak
| Description |
Titan: Larger and Larger Lakes |
| Full Description |
This radar image, obtained by Cassini's radar instrument during a near-polar flyby on Feb. 22, 2007, shows a big island smack in the middle of one of the larger lakes imaged on Saturn's moon Titan. This image offers further evidence that the largest lakes are at the highest latitudes. The island is about 90 kilometers (62 miles) by 150 kilometers (93 miles) across, about the size of Kodiak Island in Alaska or the Big Island of Hawaii. The island may actually be a peninsula connected by a bridge to a larger stretch of land. As you go farther down the image, several very small lakes begin to appear, which may be controlled by local topography. This image was taken in synthetic aperture mode at 700 meter (2,300 feet) resolution. North is toward the left. The image is centered at about 79 north degrees north and 310 degrees west. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. Credit: NASA/JPL |
| Date |
February 27, 2007 |
|
Titan (T25) Viewed by Cassin
| Description |
Titan (T25) Viewed by Cassini's Radar Feb. 22, 2007 |
| Full Description |
This image of Saturn's largest moon, Titan, obtained by Cassini's radar instrument during a near-polar flyby on Feb. 22, 2007, features dunes and lakes, one of which is larger than any lake on Earth and could be legitimately called a sea. First discovered by Cassini's radar in July 2006 (see Lakes on Titan), Titan's lakes are thought to consist of liquid methane and ethane. The image runs from southern latitudes, starting at 32 degrees south, 55 degrees west, where we see featureless terrain with bright streaks, heading north and slightly east, through dune fields interspersed with exposed bright mounds. In places, the dunes wrap around the bright mounds, which suggests the mounds are raised (see Titan Features and Interactions). In one case, the dunes wrap around an unusual rose-shaped structure, approximately 70 kilometers (40 miles) across. Near the spacecraft's closest approach (33 degrees north, 28 degrees west), where the swath is at its narrowest, the terrain is dark and mottled, with occasional bright outcrops and fine dunes. As we continue to head north, we see the first signs of the action of liquids -- fine channels and canyon-like structures. Later, depressions can be seen. These are similar to those seen in the lake region and are interpreted as volcanic calderas or drained lakes. As the swath continues, these become more plentiful, and some are partly filled with dark material thought to be liquid hydrocarbons, hence lakes. In places, the lakes reside in what appear to be nested, near-circular depressions, reminiscent of nested calderas. The final section of the swath, which is closest to the pole, contains by far the largest lakes observed by Cassini's radar to date. Part of the first of these was seen during a previous flyby (see Titan's Great Lakes?), and is fed by a long river -- over 200 kilometers (120 miles) in length, and hundreds of meters to over 1 kilometer (0.6 miles) in width - running through what appears to be a flood plain. The lake's bright, jutting shoreline indicates that old, eroded landforms may have been flooded. The end of the next lake was also observed before (see Lakes and More lakes), appearing to be, in both form and scale, similar to Lake Powell, a flooded drainage system in Utah and Arizona. We can now see that this lake on Titan connects via a relatively narrow channel to a much larger (at least 45,000 square kilometers or 17,000 square miles) lake, containing a large (approximately 12,000 square kilometers or 4,600 square miles) island or peninsula (see Titan: Larger and Larger Lakes). The last part of the image passes close to the pole (86 degrees north, 290 degrees east), before heading east and slightly south. At the end of the swath, we see the largest lake observed yet -- at least 100,000 square kilometers (39,000 square miles), which is greater in extent than one of the largest lakes on Earth, Lake Superior (82,000 square kilometers or 32,000 square miles), and covers a greater fraction of, Titan than the largest terrestrial inland sea, the Black Sea. The Black Sea covers 0.085 percent of the surface of the Earth, this newly observed body on Titan covers at least 0.12 percent of the surface of Titan. Because of its size, scientists are calling this a sea. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL |
| Date |
March 13, 2007 |
|
Titan Sea and Lake Superior
| Description |
Titan Sea and Lake Superior |
| Full Description |
This side-by-side image shows a Cassini radar image (on the left) of what is the largest body of liquid ever found on Titan's north pole, compared to Lake Superior (on the right). This close-up is part of a larger image (see Titan (T25) Viewed by Cassini's Radar - Feb. 22, 2007) and offers strong evidence for seas on Titan. These seas are most likely liquid methane and ethane. This feature on Titan is at least 100,000 square kilometers (39,000 square miles), which is greater in extent than Lake Superior (82,000 square kilometers or 32,000 square miles), which is one of Earth's largest lakes. The feature covers a greater fraction of Titan than the largest terrestrial inland sea, the Black Sea. The Black Sea covers 0.085 percent of the surface of the Earth, this newly observed body on Titan covers at least 0.12 percent of the surface of Titan. Because of its size, scientists are calling it a sea. The image on the right is from the SeaWiFS project, NASA's Goddard Space Flight Center, Greenbelt, Md. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL/GSFC |
| Date |
March 13, 2007 |
|
Powering Saturn's Jets (with
| Description |
Powering Saturn's Jets (without labels) |
| Full Description |
+ View labeled version of the image Using images like the one presented here, Cassini imaging scientists have made a major finding about the mechanism powering the general circulation of Saturn. The image shows small-scale, sheared-out cloud features associated with turbulent eddies in the vicinity of one of Saturn's eastward flowing jet streams, or "jets." The jet itself, located at 27.5 degrees south latitude, is indicated by the large horizontal arrow. Winds in this jet have blown continuously at speeds close to 320 kilometers per hour (200 miles per hour) for as long as scientists have observed Saturn. By tracking the movements of these cloud features in successive images separated by about 10 hours (about one Saturn rotation), Cassini scientists have confirmed that the eddies on either side of the jet give up their energy and momentum to help keep the winds in the jet blowing. The tilted arrows indicate the direction in which the eddies move the energy and momentum that power the jet. The winds that accomplish this are so strong that they combine to stretch out the eddies into bright, tilted streaks that are visible here, parallel to the arrows. The analysis of Cassini images covering most of Saturn's southern hemisphere suggests that similar processes occurring all over Saturn explain the remarkable decades-long stability of its alternating pattern of eastward and westward jets. The same process also occurs on Jupiter, and on Earth in the storm track along the east coast of the United States. Prior to this discovery, it was thought that the jets on Saturn and Jupiter were powered by an entirely different process, analogous to the tropical circulation on Earth. But now it appears that a comparison to the atmospheric motions in the Earth's mid-latitudes is more appropriate. The eddies seen in this image also create circulation patterns of upward and downward motion (in altitude) at different latitudes that help explain the general banded structure of global cloud patterns on the Jovian planets. A labeled version of the image is presented here as well. The image was taken using a spectral filter sensitive to wavelengths of infrared light centered at 750 nanometers. The view was acquired with the Cassini spacecraft narrow-angle camera on Feb. 5, 2005, at a distance of approximately 3.4 million kilometers (2.1 million miles) from Saturn. Image scale is 20 kilometers (12 miles) per pixel. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL/Space Science Institute |
| Date |
May 8, 2007 |
|
Coasts and Drowned Mountains
| Description |
Coasts and Drowned Mountains |
| Full Description |
On May 12, 2007, Cassini completed its 31st flyby of Saturn's moon Titan, which the team calls T30. The radar instrument obtained this image showing the coastline and numerous island groups of a portion of a large sea, consistent with the larger sea seen by the Cassini imaging instrument (See Seeing Farther North). Like other bodies of liquid seen on Titan, this feature reveals channels, islands, bays, and other features typical of terrestrial coastlines, and the liquid, most likely a combination of methane and ethane, appears very dark to the radar instrument. What is striking about this portion of the sea compared to other liquid bodies on Titan is the relative absence of brighter regions within it, suggesting that the depth of the liquid here exceeds tens of meters (tens of yards). Of particular note is the presence of isolated islands, which follow the same direction as the peninsula to their lower right, suggesting that they may be part of a mountain ridgeline that has been flooded. This is analogous to, for example, Catalina Island off the coast of Southern California. The image as shown is about 160 kilometers (100 miles) by 270 kilometers (170 miles) at 300-meter (980-foot) resolution. The image is centered near 70 degrees north latitude and 310 west longitude. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA''s Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov *Credit:* NASA/JPL |
| Date |
May 23, 2007 |
|
Titan (T28) Viewed by Cassin
| Description |
Titan (T28) Viewed by Cassini's Radar April 10, 2007 |
| Full Description |
Cassini's radar instrument obtained another in its series of north polar swaths of Titan on April 10, 2007. This image exposes more of the transition between the mid-latitudes and the polar area, and extends coverage of the lakes region previously described in Titan (T25) Viewed by Cassini's Radar - Feb. 22, 2007. This swath begins at 20 degrees south, 37 degrees west, continuing approximately north-northeast. Although it appears to be straight in this image, its path on Titan curves gently toward the east until it reaches 80 degrees north at 300 degrees west, then it turns south and ends at 51 degrees north, 213 degrees west. The swath width varies from about 200 kilometers (120 miles) at its center to about 500 kilometers (310 miles) at the ends, and is more than 6,700 kilometers (4,100 miles) long. Beginning at the left end of the image as shown, we see the dark sinuous features previously interpreted to be dunes, interspersed with bright features that appear to be higher. In some cases the dunes seem to bend around the bright features, and in others they may be climbing up onto them, both behaviors are commonly seen in dune fields on Earth. About one-third of the way through the swath, the dunes become rare and then disappear, to be replaced by more linear features. Some of these have rounded and brighter ends, similar to lava flows on Earth (in synthetic aperture radar images, rougher features appear as bright). Just past the midway point, we find relatively flat and featureless terrain with some structures that also resemble flow fronts, followed by a complex area of semi-circular to irregular depressions that may have formed by collapse. These give way to the lakes at the northernmost portion. Here T28 overlaps with the T25 synthetic aperture radar swath (see Titan (T25) Viewed by Cassini's Radar - Feb. 22, 2007), offering stereo coverage that will be used to determine feature heights. The lakes, which are thought to be filled with a combination of methane and ethane, have complex shorelines that often include channels. Some of these channels have well-developed tributary systems and drain many thousands of square kilometers of the surrounding terrain. As shown in the mosaic (see Exploring the Wetlands of Titan), these lakes are likely connected, and may form part of a larger sea. Brighter areas within the lakes may represent the lake bottom Âż at the radar's 2-centimeter wavelength, it is possible that the liquid is transparent for many tens of meters (tens of yards) to the radar, allowing a reflection to be returned from the lake bottom. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and, the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL |
| Date |
July 27, 2007 |
|
Titan (T30) Viewed by Cassin
| Description |
Titan (T30) Viewed by Cassini's Radar May 12, 2007 |
| Full Description |
This north polar image of Titan was acquired by Cassini's radar instrument on May 12, 2007. Stretching from 69 degrees north, 329 degrees west to 33 degrees north, 227 degrees west, this swath gently curves from west-to-east at the left end to north-to-south at the right. It is more than 2,700 kilometers (1,678 miles) long and varies from 200 to 500 kilometers (124 to 310 miles) in width, covering the southern extreme of a large dark area previously imaged by the Imaging Science Subsystem (see Exploring the Wetlands of Titan). The thin white stripe at immediate left is an artifact related to the instrument's multi-beam operation, throughout the swath there are some near-vertical stripes that are also artifacts. As displayed here, the extreme left end of the image shows the west margin of a dark area interpreted to be a lake of liquid methane and probably ethane, with obvious shore-like features, such as bays, inlets and islands. Radar images show smooth areas as dark, and this lake is among the darkest areas seen so far on Titan. The eastern margin of the lake is similarly complex, and some of the shoreline features seem related to ridges and lower topography on the shore, as if the liquid in the lake has filled lower-lying areas between ridges. Some of these channels drain into the lake, while others go into a slightly brighter, more uniform area that may be connected to the lake just off the lower edge of the image (for more details on this area, see Coasts and Drowned Mountains). Farther to the right, moving southward, a complex region of ridges and channels transitions to more subdued landforms with circular or lobate features, some of which have raised rims. The terrain toward the right of the image is rougher, with topographic depressions that resemble dried lakebeds, lacking the dark material seen in the lakes farther north. Toward the right end of the image, farthest from the north pole, a series of long, low depressions is seen against a relatively dark background. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL |
| Date |
August 13, 2007 |
|
Radar Sees Lakes in Titan's
| Description |
Cassini's radar instrument finds lakes in the southern hemisphere of Titan during the most recent Titan flyby. |
| Full Description |
Cassini's radar instrument finds lakes in the southern hemisphere of Titan during the most recent Titan flyby. This is the first confirmation of lakes in the southern hemisphere with the radar instrument. Hundreds of lakes have already been discovered and imaged by radar at Titan's north pole. This finding is important to scientists who are trying to understand how Titan's environment works. Cassini completed its 37th flyby of Saturn's moon Titan on Oct. 2, 2007, allowing the Cassini Titan Radar Mapper to obtain this southernmost image to date. Shown here is a portion of the image swath and an inset with details of a small portion in false color. Titan's south pole is at the bottom center. The nature and similarities between the northern and southern near-polar regions supports the idea that much of Titan's poles are climate-driven. A few small dark patches - liquid-hydrocarbon-filled lakes - stand out, at about 70 degrees south, and are highlighted in the insert (lakes are colored blue). Other features in the scene include broad, steep-sided depressions adjoined to sinuous depressions, interpreted to be empty topographic basins or drained lakes fed by channels, and complex mottled terrain, akin to those at similar northern latitudes. Similarities in features between northern and southern hemispheres imply that the climatic conditions are also similar. The image shown here is a 1.4-kilometer (0.87-mile) resolution, 2,250-kilometer (1,400 mile) subsection of a 4,500-kilometer (2,800-mile) long swath, which is 150 kilometers (93 miles) wide at the narrowest point. The insert is 90 by 90 kilometers (56 by 56 miles), centered at 70.5 degrees south and 113.9 degrees west. Future southern flybys will image closer to the pole and are expected to show more lakes. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm . Credit: NASA/JPL/USGS |
| Date |
October 11, 2007 |
|
Ganesa Macula
| Description |
This radar image of Titan shows Ganesa Macula, interpreted as a cryovolcano (ice volcano), and its surroundings. |
| Full Description |
This radar image of Titan shows Ganesa Macula, interpreted as a cryovolcano (ice volcano), and its surroundings. Cryovolcanism is thought to have been an important process on Titan and may still be happening today. This mosaic was made from images obtained by the Cassini radar mapper on two flybys. The lower part of the image was from the flyby on Oct. 26, 2004, while the upper part was from the Jan. 13, 2007, flyby. Ganesa macula is the dark circular feature seen on the lower left of the mosaic. Bright rounded features, interpreted as cryovolcanic flows, are seen towards the top and the right of the mosaic. This image mosaic was taken in synthetic aperture mode. The resolution of the images is approximately 350 meters (1,150 feet). North is toward the top. The image mosaic is about 570 kilometers (354 miles) wide and 390 kilometers (240 miles) high. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. Credit: NASA/JPL |
| Date |
February 16, 2007 |
|
Titan Features and Interacti
| Description |
This radar image, obtained by Cassini's radar instrument during a near-polar flyby on Feb. 22, 2007, shows dunes surrounding a bright feature on Saturn's moon Titan. |
| Full Description |
This radar image, obtained by Cassini's radar instrument during a near-polar flyby on Feb. 22, 2007, shows dunes surrounding a bright feature on Saturn's moon Titan. Dunes have been previously seen on Titan, so far concentrated near the equator. They are thought to be composed of small hydrocarbon or water ice particles -- probably about 250 microns in diameter, similar to sand grains on Earth. These are formed into dunes by the prevailing west-to-east surface winds. Because of the shape and length of the dunes, they are probably "longitudinal" (lying in the same direction as the average wind) rather than transverse dunes, which form across the wind and are more common on Earth. There are several kinds of interaction between the dunes and the brighter features in this image. At the left, the dunes seem to be covering the bright material, while at the center and right, they seem to be terminated against it. At the lower center and lower right, they flow around it (see also Swimming in Dunes and Dunes and More Dunes). These various interactions will help us to determine the nature of both of these features. This image was taken in synthetic aperture mode at 700-meter (2,300-foot) resolution. North is toward the left. The image is centered at about 3.5 degrees south latitude and 37.3 degrees west longitude. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. Credit: NASA/JPL |
| Date |
March 1, 2007 |
|
Powering Saturn's Jets (with
| Description |
Powering Saturn's Jets (with labels) |
| Full Description |
+ View unlabeled, uncropped version of the image Using images like the one presented here, Cassini imaging scientists have made a major finding about the mechanism powering the general circulation of Saturn. The image shows small-scale, sheared-out cloud features associated with turbulent eddies in the vicinity of one of Saturn's eastward flowing jet streams, or "jets." The jet itself, located at 27.5 degrees south latitude, is indicated by the large horizontal arrow. Winds in this jet have blown continuously at speeds close to 320 kilometers per hour (200 miles per hour) for as long as scientists have observed Saturn. By tracking the movements of these cloud features in successive images separated by about 10 hours (about one Saturn rotation), Cassini scientists have confirmed that the eddies on either side of the jet give up their energy and momentum to help keep the winds in the jet blowing. The tilted arrows indicate the direction in which the eddies move the energy and momentum that power the jet. The winds that accomplish this are so strong that they combine to stretch out the eddies into bright, tilted streaks that are visible here, parallel to the arrows. The analysis of Cassini images covering most of Saturn's southern hemisphere suggests that similar processes occurring all over Saturn explain the remarkable decades-long stability of its alternating pattern of eastward and westward jets. The same process also occurs on Jupiter, and on Earth in the storm track along the east coast of the United States. Prior to this discovery, it was thought that the jets on Saturn and Jupiter were powered by an entirely different process, analogous to the tropical circulation on Earth. But now it appears that a comparison to the atmospheric motions in the Earth's mid-latitudes is more appropriate. The eddies seen in this image also create circulation patterns of upward and downward motion (in altitude) at different latitudes that help explain the general banded structure of global cloud patterns on the Jovian planets. An unlabeled, uncropped version of the image is presented here as well. The image was taken using a spectral filter sensitive to wavelengths of infrared light centered at 750 nanometers. The view was acquired with the Cassini spacecraft narrow-angle camera on Feb. 5, 2005, at a distance of approximately 3.4 million kilometers (2.1 million miles) from Saturn. Image scale is 20 kilometers (12 miles) per pixel. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the, Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL/Space Science Institute |
| Date |
May 8, 2007 |
|
CRISM Views Phobos and Deimo
| title |
CRISM Views Phobos and Deimos |
| date |
10.22.2007 |
| description |
Phobos' surface contains a second material, grayer-colored ejecta from a 9-kilometer (5.6-mile) diameter crater. This crater, called Stickney, is located at the upper left limb of Phobos and the grayer-colored ejecta extends toward the lower right. These CRISM measurements are the first spectral measurements to resolve the disk of Deimos, and the first of this part of Phobos to cover the full wavelength range needed to assess the presence of iron-, water-, and carbon-containing minerals. The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad. Credit: NASA/JPL/JHUAPL, These two images taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) show Mars' two small moons, Phobos and Deimos, as seen from the Mars Reconnaissance Orbiter's low orbit around Mars. Both images were taken while the spacecraft was over Mars' night side, with the spacecraft turned off its normal nadir-viewing geometry to glimpse the moons. The image of Phobos, shown at the top, was taken at 0119 UTC on October 23 (9:19 p.m. EDT on Oct. 22), and shows features as small as 400 meters (1,320 feet) across. The image of Deimos, shown at the bottom, was taken at 2016 UTC (12:16 p.m. EDT) on June 7, 2007, and shows features as small as 1.3 kilometers (0.8 miles) across. Both CRISM images were taken in 544 colors covering 0.36-3.92 micrometers, and are displayed at twice the size in the original data for viewing purposes. Phobos and Deimos are about 21 and 12 kilometers (13.0 and 7.5 miles) in diameter and orbit Mars with periods of 7 hours, 39.2 minutes and 1 day, 6 hours, 17.9 minutes respectively. Because Phobos orbits Mars in a shorter time than Mars' 24 hour, 37.4-minute rotational period, to an observer on Mars' surface it would appear to rise in the west and set in the east. From Mars' surface, Phobos appears about one-third the diameter of the Moon from Earth, whereas Deimos appears as a bright star. The moons were discovered in 1877 by the astronomer Asaph Hall, and as satellites of a planet named for the Roman god of war, they were named for Greek mythological figures that personify fear and terror. The first spacecraft measurements of Phobos and Deimos, from the Mariner 9 and Viking Orbiter spacecraft, showed that both moons have dark surfaces reflecting only 5 to 7% of the sunlight that falls on them. The first reconstruction of the moons' spectrum of reflected sunlight was a difficult compilation from three different instruments, and appeared to show a flat, grayish spectrum resembling carbonaceous chondrite meteorites. Carbonaceous chondrites are primitive carbon-containing materials thought to originate in the outer part of the asteroid belt. This led to a commonly held view among planetary scientists that Mars' moons are primitive asteroids captured into Martian orbit early in the planet's history. More recent measurements have shown that the moons are in fact relatively red in their color, and resemble even more primitive D-type asteroids in the outer solar system. Those ultra-primitive bodies are also thought to contain carbon as well as water ice, but to have experienced even less geochemical processing than many carbonaceous chondrites. The version of the CRISM images shown here were constructed by displaying 0.90, 0.70, and 0.50 micrometer wavelengths in the red, green, and blue image planes. This is a broader range of colors than is visible to the human eye, but it accentuates color differences. Both moons are shown with colors scaled in the same way. Deimos is red-colored like most of Phobos. However, |
|
Hubble Discovers Dark Cloud
| Title |
Hubble Discovers Dark Cloud in the Atmosphere of Uranus |
|
ACD07-0092-038
Dr Condoleezza Rice, United
5/24/07
| Description |
Dr Condoleezza Rice, United States Secretary of State visits Ames. Takes a demonstration ride in the Tesla Motors Electric Car. Australian Foreign Minister Alexander Downer traveling with Dr Rice addresses the assembled media and Ames staffers |
| Date |
5/24/07 |
|
Black Pine 2 Fire, Idaho
| Title |
Black Pine 2 Fire, Idaho |
| Description |
East of the Raft River in southern Idaho, the Black Pine 2 Fire had scorched more than 50,000 acres of grassland, brush, and juniper as of July 11, 2007, according to the morning report from the National Interagency Fire Center. This image of the fire was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite on July 10. The area in which MODIS detected actively burning fire is outlined in red. Smoke spreads east and mingles with clouds. The burned area appears a deep brown against the tan color of the grasslands and the dull green of forests on mountain slopes. Green circles that line the Raft River and tributaries are fields watered with a center-pivot irrigation system. At the top of the image is Lake Walcott, which is on the Snake River. The large image provided above has a spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response Team provides twice-daily [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA1 ] images of the western United States in additional resolutions and formats, including an infrared-enhanced version that makes burned areas appear brick red. NASA image courtesy the MODIS Rapid Response Team, [ http://rapidfire.sci.gsfc.nasa.gov ] Goddard Space Flight Center |
|
Floods in Texas and Oklahoma
| Title |
Floods in Texas and Oklahoma |
| Description |
Heavy rains pounded the Southern Plains of the United States during mid-June when moisture from the Gulf of Mexico streamed northward into a slow-moving frontal system. The result was extensive flooding over parts of Texas and Oklahoma. On Monday, June 18, 2007, six flood-related deaths were reported in northern Texas as storms dumped up to 8 inches (abut 200 millimeters) of rain in the area. On Tuesday, additional storms dumped heavy rains over parts of northwestern Oklahoma, forcing several road closures, said news reports. This image shows rainfall totals for June 14 through June 20, 2007. The rainfall totals are from the near-real-time, Multi-satellite Precipitation Analysis (MPA), which is based on measurements taken by the Tropical Rainfall Measuring Mission (TRMM [ http://trmm.gsfc.nasa.gov/ ]) satellite. The MPA analysis indicates that during this time more than 200 millimeters (about 8 inches, red area) of rain fell in northern Texas just south of the Oklahoma border, where flooding was reported. A much broader area of at least 150 to 200 millimeters (about 6 to 8 inches) of rain covers most of northwest Oklahoma. Based on these totals, the TRMM team predicted that flooding was likely or occurring. The group produces a global map [ http://trmm.gsfc.nasa.gov/publications_dir/potential_flood.html ] indicating where there is a high potential for flooding based on rainfall totals. TRMM is a joint mission between NASA and the Japanese space agency, JAXA. Image produced by Hal Pierce (SSAI/NASA GSFC) and caption by Hal Pierce and Steve Lang (SSAI/NASA GSFC). |
|
Floods in Texas and Oklahoma
| Title |
Floods in Texas and Oklahoma |
| Description |
June 2007 was exceptionally wet for the Southern Plains of the United States because a stagnant weather pattern focused moisture and storms over Texas and Oklahoma. The latest round of heavy storms dumped up to 460 millimeters (18 inches) of rain in parts of central Texas on the night of Tuesday, June 26, said news reports. For Austin, the state's capital, more than 30 inches of rain has fallen since January, making 2007 the wettest year on record so far according to local news reports. This image shows rainfall totals from the near-real-time, Multi-satellite Precipitation Analysis (MPA), which is based on rainfall data collected by the Tropical Rainfall Measuring Mission TRMM [ http://trmm.gsfc.nasa.gov/ ]) satellite. The totals shown here indicate how much rain fell between June 20 and June 28, 2007. Splotches of red over central Texas and southern Oklahoma indicate where the MPA tallied up to 200 millimeters (8 inches) of rain. A broad area of at least 50 mm (about 2 inches) of rainfall covers almost all of Texas and Oklahoma. These totals fall short of totals reported on the ground because the satellites used in the MPA can't see areas of localized heavy rain. These satellites "zoom in" to approximately 30 kilometers (20 miles), and so miss smaller areas of intense rain. TRMM is a joint mission between NASA and the Japanese space agency, JAXA. Image produced by Hal Pierce (SSAI/NASA GSFC) and caption by and Steve Lang (SSAI/NASA GSFC). |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
The rivers of northwestern Missouri were still swollen in the wake of intense spring storms when the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image on May 10, 2007. The image is made from a combination of infrared and visible light to make the floods more visible than they would be in a photo-like image. In this type of image, water is dark blue or black, clouds are light blue and white, plant-covered land is bright green, and bare earth is pink-tinted tan. Fires are outlined with red boxes. The Missouri River runs along the left edge of the image, then curves east along the bottom of the image. Though the most flooded regions were covered in clouds, a few breaks reveal that the Missouri was swollen far beyond its banks. Nestled in a bend in the river near the Nebraska, Kansas, and Missouri border is the town of Big Lake. The image shows that the river's curve has turned into a broad lake. The town was completely submerged in the flood when levees along the river broke, reported the Associated Press. [ http://www.cnn.com/2007/WEATHER/05/11/missouri.flooding.ap/index.html ] Beyond Big Lake, many communities along the Grand and the Platte Rivers and their tributaries have also been flooded or threatened by floods. All of these rivers are clearly running high in the image. MODIS captured the lower image on April 29, 2007, not quite a week before the rains began. By providing a clear view of normal water levels, the image illustrates just how extensively the rivers were flooded on May 10. Photo-like versions of both the April 29 [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007119/USA3.2007119.aqua ] and May 10 [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007130/USA3.2007130.terra ] images are available from the MODIS Rapid Response System. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
The rivers of northwestern Missouri were still swollen in the wake of intense spring storms when the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image on May 10, 2007. The image is made from a combination of infrared and visible light to make the floods more visible than they would be in a photo-like image. In this type of image, water is dark blue or black, clouds are light blue and white, plant-covered land is bright green, and bare earth is pink-tinted tan. Fires are outlined with red boxes. The Missouri River runs along the left edge of the image, then curves east along the bottom of the image. Though the most flooded regions were covered in clouds, a few breaks reveal that the Missouri was swollen far beyond its banks. Nestled in a bend in the river near the Nebraska, Kansas, and Missouri border is the town of Big Lake. The image shows that the river's curve has turned into a broad lake. The town was completely submerged in the flood when levees along the river broke, reported the Associated Press. [ http://www.cnn.com/2007/WEATHER/05/11/missouri.flooding.ap/index.html ] Beyond Big Lake, many communities along the Grand and the Platte Rivers and their tributaries have also been flooded or threatened by floods. All of these rivers are clearly running high in the image. MODIS captured the lower image on April 29, 2007, not quite a week before the rains began. By providing a clear view of normal water levels, the image illustrates just how extensively the rivers were flooded on May 10. Photo-like versions of both the April 29 [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007119/USA3.2007119.aqua ] and May 10 [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007130/USA3.2007130.terra ] images are available from the MODIS Rapid Response System. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
Early May 2007 brought torrential spring rains to the Midwestern United States, and by May 9, the National Weather Service [ http://www.nws.noaa.gov/oh/hic/ ] had recorded flooding at 111 locations from North Dakota to Texas. At 15 locations, many of which were in Missouri, gauges measured major flooding. Thousands of people fled as the Missouri burst through levees in Missouri and Kansas, reported the Associated Press [ http://www.cnn.com/2007/WEATHER/05/09/missouri.flooding.ap/index.html ] on May 9. The Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite captured the top image of floods along the Missouri River and its tributaries on May 8. Though clouds still covered much of the Midwest on May 8, a few breaks revealed the flood-swollen Missouri, Grand, and Thompson Rivers. The large image shows additional flooding in Missouri, Iowa, and Kansas. Both this and the lower image, taken on April 29 before the rains began to fall, were made with a combination of visible and infrared light to highlight the presence of water on the ground. In this type of image, clouds are pale blue and white, water is dark blue or black, plant-covered land is green, and bare earth is tan pink. The tan and green speckled appearance of the landscape seen in the lower image is typical of agricultural land. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3 ] of the Midwest are available from the MODIS Rapid Response System. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
Early May 2007 brought torrential spring rains to the Midwestern United States, and by May 9, the National Weather Service [ http://www.nws.noaa.gov/oh/hic/ ] had recorded flooding at 111 locations from North Dakota to Texas. At 15 locations, many of which were in Missouri, gauges measured major flooding. Thousands of people fled as the Missouri burst through levees in Missouri and Kansas, reported the Associated Press [ http://www.cnn.com/2007/WEATHER/05/09/missouri.flooding.ap/index.html ] on May 9. The Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite captured the top image of floods along the Missouri River and its tributaries on May 8. Though clouds still covered much of the Midwest on May 8, a few breaks revealed the flood-swollen Missouri, Grand, and Thompson Rivers. The large image shows additional flooding in Missouri, Iowa, and Kansas. Both this and the lower image, taken on April 29 before the rains began to fall, were made with a combination of visible and infrared light to highlight the presence of water on the ground. In this type of image, clouds are pale blue and white, water is dark blue or black, plant-covered land is green, and bare earth is tan pink. The tan and green speckled appearance of the landscape seen in the lower image is typical of agricultural land. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3 ] of the Midwest are available from the MODIS Rapid Response System. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
After two weeks of clouds and rain, the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov ] satellite captured its first clear view of floods in the Missouri River system on May 12, 2007. Though the floods had started to subside by this time, the Missouri and Grand Rivers still stretch kilometers over their banks. Subsequent images, taken on May 13 [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007133 ] and May 14, [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007134 ] reveal that the rivers are slowly returning to normal as water drains downstream. The lower image, taken on April 29, shows the rivers under normal conditions. Both images use a combination of visible and infrared light to increase the contrast between mud-laden water and earth. In this type of image, water is dark blue or black. Tiny squares of plant-covered farmland are bright green, and sections of bare earth, such as the Missouri River's wide flood plain, are tan-pink. A red box outlines a fire in the lower image. The rains that triggered the floods also spurred plant growth. By May 12, an intense green replaced many of the tan squares that were visible on April 29. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
After two weeks of clouds and rain, the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov ] satellite captured its first clear view of floods in the Missouri River system on May 12, 2007. Though the floods had started to subside by this time, the Missouri and Grand Rivers still stretch kilometers over their banks. Subsequent images, taken on May 13 [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007133 ] and May 14, [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007134 ] reveal that the rivers are slowly returning to normal as water drains downstream. The lower image, taken on April 29, shows the rivers under normal conditions. Both images use a combination of visible and infrared light to increase the contrast between mud-laden water and earth. In this type of image, water is dark blue or black. Tiny squares of plant-covered farmland are bright green, and sections of bare earth, such as the Missouri River's wide flood plain, are tan-pink. A red box outlines a fire in the lower image. The rains that triggered the floods also spurred plant growth. By May 12, an intense green replaced many of the tan squares that were visible on April 29. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
After a week of clouds and rain, the skies cleared over the midwestern United States on August 25, 2007, giving the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) flying on NASA's Terra [ http://terra.nasa.gov/ ] satellite this view of the region's swollen rivers. A string of severe thunderstorms [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14462 ] pounded the U.S. Midwest during the third week of August, leaving devastating floods in their wake. Though the floods had started to recede by the time MODIS captured the top image, the Mississippi and Wisconsin Rivers and their tributaries were still running high. The lower image shows the river system in southeastern Minnesota, northeastern Iowa, and western Wisconsin on August 10, before the storms came through. Both images were made with a combination of infrared and visible light, which makes water appear black, while the surrounding plant-covered land is bright green. A comparison between the two images reveals that the Mississippi River was overflowing, dark pools of water surround its banks in the top image. The Wisconsin River looks only slightly swollen, but its tributaries, too small to be visible in early August, have widened enough to show up clearly. At least 18 deaths have been blamed on the storms and floods, reported the Associated Press on August 26. These images are displayed at MODIS' maximum resolution of 250 meters per pixel. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007237 ] of the United States are available from the MODIS Rapid Response System in a variety of resolutions. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
After a week of clouds and rain, the skies cleared over the midwestern United States on August 25, 2007, giving the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) flying on NASA's Terra [ http://terra.nasa.gov/ ] satellite this view of the region's swollen rivers. A string of severe thunderstorms [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14462 ] pounded the U.S. Midwest during the third week of August, leaving devastating floods in their wake. Though the floods had started to recede by the time MODIS captured the top image, the Mississippi and Wisconsin Rivers and their tributaries were still running high. The lower image shows the river system in southeastern Minnesota, northeastern Iowa, and western Wisconsin on August 10, before the storms came through. Both images were made with a combination of infrared and visible light, which makes water appear black, while the surrounding plant-covered land is bright green. A comparison between the two images reveals that the Mississippi River was overflowing, dark pools of water surround its banks in the top image. The Wisconsin River looks only slightly swollen, but its tributaries, too small to be visible in early August, have widened enough to show up clearly. At least 18 deaths have been blamed on the storms and floods, reported the Associated Press on August 26. These images are displayed at MODIS' maximum resolution of 250 meters per pixel. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007237 ] of the United States are available from the MODIS Rapid Response System in a variety of resolutions. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
Water levels on the Blanchard River in northwestern Ohio reached near-record levels a short time after the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image at 12:30 p.m. Eastern Daylight Time, on August 22, 2007. At 1:00 p.m., National Weather Service gauges [ http://newweb.erh.noaa.gov/ahps2/hydrograph.php?wfo=cle&gage=fdyo1&view=1,1,1,1,1,1,1,1&toggles=10,7,8,2,9,15,6 ] in Findlay, Ohio, recorded water levels of 18.46 feet, just under six and a half inches short of the record crest of 18.5 feet set on March 13, 1913. In both cases, the river rose more than seven feet above its flood stage of 11 feet. The August 22 flood swamped the city of Findlay, forcing hundreds from their homes and putting the city in a state of emergency, reported the Associated Press on August 23. The disastrous floods along the Blanchard River can be seen in the top image. The image was made with a combination of visible and infrared light to increase the contrast between water and land. Water is dark blue or black, while plant-covered land is bright green. Tiny squares of plant-free land, most like fallow fields in this case, are tan. Cities are gray, looking like a dark smudge against the bright green landscape. Lingering clouds are light blue and white. The severity of the flood can be gauged by comparing the top image with the lower image, which was taken on August 13, 2007. In the lower image, the Blanchard River is too small to be visible. By August 22, the river and many of its tributaries are clearly visible. The river expands over Findlay, and then bends south. Ohio was not the only state that experienced floods in mid-August. A string of severe thunderstorms [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14462 ] dumped heavy rain on several Midwest states, including Minnesota, Wisconsin, Iowa, Illinois, Indiana, and Ohio. At the same time, the remnants of Tropical Storm Erin [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14454 ] triggered deadly flooding in Oklahoma and Texas. These images are shown at MODIS' maximum resolution of 250 meters per pixel. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007234 ] of the U.S. Midwest are available from the MODIS Rapid Response System in a variety of resolutions. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
Water levels on the Blanchard River in northwestern Ohio reached near-record levels a short time after the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image at 12:30 p.m. Eastern Daylight Time, on August 22, 2007. At 1:00 p.m., National Weather Service gauges [ http://newweb.erh.noaa.gov/ahps2/hydrograph.php?wfo=cle&gage=fdyo1&view=1,1,1,1,1,1,1,1&toggles=10,7,8,2,9,15,6 ] in Findlay, Ohio, recorded water levels of 18.46 feet, just under six and a half inches short of the record crest of 18.5 feet set on March 13, 1913. In both cases, the river rose more than seven feet above its flood stage of 11 feet. The August 22 flood swamped the city of Findlay, forcing hundreds from their homes and putting the city in a state of emergency, reported the Associated Press on August 23. The disastrous floods along the Blanchard River can be seen in the top image. The image was made with a combination of visible and infrared light to increase the contrast between water and land. Water is dark blue or black, while plant-covered land is bright green. Tiny squares of plant-free land, most like fallow fields in this case, are tan. Cities are gray, looking like a dark smudge against the bright green landscape. Lingering clouds are light blue and white. The severity of the flood can be gauged by comparing the top image with the lower image, which was taken on August 13, 2007. In the lower image, the Blanchard River is too small to be visible. By August 22, the river and many of its tributaries are clearly visible. The river expands over Findlay, and then bends south. Ohio was not the only state that experienced floods in mid-August. A string of severe thunderstorms [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14462 ] dumped heavy rain on several Midwest states, including Minnesota, Wisconsin, Iowa, Illinois, Indiana, and Ohio. At the same time, the remnants of Tropical Storm Erin [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14454 ] triggered deadly flooding in Oklahoma and Texas. These images are shown at MODIS' maximum resolution of 250 meters per pixel. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007234 ] of the U.S. Midwest are available from the MODIS Rapid Response System in a variety of resolutions. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
August 2007 was the wettest month ever recorded for many places in Minnesota, Iowa, and Wisconsin, with rainfall totals ranging from 23.86 inches in Hokah, Minnesota, to 12.79 inches in Winona Dam, Minnesota, said the National Weather Service. [ http://www.crh.noaa.gov/crnews/display_story.php?wfo=arx&storyid=9990&source=0 ] While the entire month was rainy, much of the rain fell on August 18-20, when several thunderstorms rolled across the region. The thunderstorms triggered disastrous flooding in several Midwest communities, including La Crosse, Wisconsin. A little over 10 inches of rain fell in La Crosse in the 24-hour period that spanned August 18 and August 19, and flash floods resulted. Combined with rains from the rest of August, this rainfall let La Crosse set a new monthly precipitation record of 17 inches. By August 27, when the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) captured the top image, the floods had largely retreated, though visible signs of flooding remained. Compared to the lower image, acquired on September 7, 2006, the landscape to the west of the Mississippi River is pocked with pools of water. The city of La Crosse, the bright white and gray grid on the east side of the river, appears to have dried out. The city appears much as it did nearly a year earlier with no visible sign of flooding. You can download a 15-meter-resolution KMZ file of the 2007 image of La Crosse [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/Sep2007/lacrosse_ast_2007239.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image created by Jesse Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
|
Floods in the Midwestern Uni
| Title |
Floods in the Midwestern United States |
| Description |
August 2007 was the wettest month ever recorded for many places in Minnesota, Iowa, and Wisconsin, with rainfall totals ranging from 23.86 inches in Hokah, Minnesota, to 12.79 inches in Winona Dam, Minnesota, said the National Weather Service. [ http://www.crh.noaa.gov/crnews/display_story.php?wfo=arx&storyid=9990&source=0 ] While the entire month was rainy, much of the rain fell on August 18-20, when several thunderstorms rolled across the region. The thunderstorms triggered disastrous flooding in several Midwest communities, including La Crosse, Wisconsin. A little over 10 inches of rain fell in La Crosse in the 24-hour period that spanned August 18 and August 19, and flash floods resulted. Combined with rains from the rest of August, this rainfall let La Crosse set a new monthly precipitation record of 17 inches. By August 27, when the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER [ http://asterweb.jpl.nasa.gov/ ]) captured the top image, the floods had largely retreated, though visible signs of flooding remained. Compared to the lower image, acquired on September 7, 2006, the landscape to the west of the Mississippi River is pocked with pools of water. The city of La Crosse, the bright white and gray grid on the east side of the river, appears to have dried out. The city appears much as it did nearly a year earlier with no visible sign of flooding. You can download a 15-meter-resolution KMZ file of the 2007 image of La Crosse [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/Sep2007/lacrosse_ast_2007239.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image created by Jesse Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. [ http://asterweb.jpl.nasa.gov/ ] |
|
Floods in the Southern and M
| Title |
Floods in the Southern and Midwestern United States |
| Description |
River systems throughout northern Texas, Arkansas, and Louisiana were swollen with winter rain when the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite captured the top image on January 21, 2007. The National Weather Service had issued warnings of mild flooding on many of the rivers shown in this image, but by January 22, the high water had begun to subside. The floods followed a powerful winter storm [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17530 ] that dumped heavy rain on the South, and ice and snow on the Midwest. The lower image shows Texas, Arkansas, and Louisiana on January 10, before the storm struck. Like the top image, the lower image was made with both infrared and visible light to increase the contrast between water and land. In this type of image, water is black or dark blue, while plant-covered land is bright green and bare or lightly vegetated ground is tan. The city of Shreveport, Louisiana, is the grey area on the banks of the Red River. Clouds are pale blue and white. True-color, photo-like images are also available from the MODIS Rapid Response Team. [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA7 ] NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Southern and M
| Title |
Floods in the Southern and Midwestern United States |
| Description |
River systems throughout northern Texas, Arkansas, and Louisiana were swollen with winter rain when the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite captured the top image on January 21, 2007. The National Weather Service had issued warnings of mild flooding on many of the rivers shown in this image, but by January 22, the high water had begun to subside. The floods followed a powerful winter storm [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17530 ] that dumped heavy rain on the South, and ice and snow on the Midwest. The lower image shows Texas, Arkansas, and Louisiana on January 10, before the storm struck. Like the top image, the lower image was made with both infrared and visible light to increase the contrast between water and land. In this type of image, water is black or dark blue, while plant-covered land is bright green and bare or lightly vegetated ground is tan. The city of Shreveport, Louisiana, is the grey area on the banks of the Red River. Clouds are pale blue and white. True-color, photo-like images are also available from the MODIS Rapid Response Team. [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA7 ] NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Southern and M
| Title |
Floods in the Southern and Midwestern United States |
| Description |
The rivers of northeast Arkansas were running high on January 24, 2007, when the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image. The National Weather Service warned residents of minor flooding along the White River on January 24, and the river was expected to remain high for several days. The floods followed a strong winter storm, [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17530 ] which coated the Midwest United States with rain, ice, and snow on January 15 and January 16. The lower image shows normal conditions on the river as seen by Terra MODIS on January 10. Both images were made with a combination of visible and infrared light. Water is dark blue or black, vegetation is green, and clouds are pale blue and white. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA7/2007024 ] of the United States are available from the MODIS Rapid Response System. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Southern and M
| Title |
Floods in the Southern and Midwestern United States |
| Description |
The rivers of northeast Arkansas were running high on January 24, 2007, when the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured the top image. The National Weather Service warned residents of minor flooding along the White River on January 24, and the river was expected to remain high for several days. The floods followed a strong winter storm, [ http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17530 ] which coated the Midwest United States with rain, ice, and snow on January 15 and January 16. The lower image shows normal conditions on the river as seen by Terra MODIS on January 10. Both images were made with a combination of visible and infrared light. Water is dark blue or black, vegetation is green, and clouds are pale blue and white. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA7/2007024 ] of the United States are available from the MODIS Rapid Response System. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Southern and M
| Title |
Floods in the Southern and Midwestern United States |
| Description |
At the point where Illinois, Kentucky, and Indiana meet, the Wabash River flows into the Ohio River, which in turn will eventually feed the Mississippi River. The two rivers are susceptible to flooding in the winter and spring, and by the end of January 2007, the confluence of the Wabash and the Ohio bulged with water. The floods came after a series of winter storms pummeled the Midwest United States in mid-January. The effect of the storms on the rivers is clear from this pair of false-color images, taken by the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite. The images are made with a combination and infrared and visible light, which makes water much more visible than it would be in a photo-like image. In this combination of wavelengths, water is dark blue or black, plant-covered land is green, sparsely vegetated or bare ground is tan-pink, and burned ground is red-brown. Icy clouds are light blue, while water clouds are white. The top image was take on January 23, 2007, shortly after the storm clouds cleared. Compared to the lower image, which was taken on January 2, the Wabash, Ohio, and Little Wabash Rivers are all swollen. By January 25, [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007025 ] the floods appeared to be receding. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007025 ] of the Midwest are available from the MODIS Rapid Response System. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Floods in the Southern and M
| Title |
Floods in the Southern and Midwestern United States |
| Description |
At the point where Illinois, Kentucky, and Indiana meet, the Wabash River flows into the Ohio River, which in turn will eventually feed the Mississippi River. The two rivers are susceptible to flooding in the winter and spring, and by the end of January 2007, the confluence of the Wabash and the Ohio bulged with water. The floods came after a series of winter storms pummeled the Midwest United States in mid-January. The effect of the storms on the rivers is clear from this pair of false-color images, taken by the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite. The images are made with a combination and infrared and visible light, which makes water much more visible than it would be in a photo-like image. In this combination of wavelengths, water is dark blue or black, plant-covered land is green, sparsely vegetated or bare ground is tan-pink, and burned ground is red-brown. Icy clouds are light blue, while water clouds are white. The top image was take on January 23, 2007, shortly after the storm clouds cleared. Compared to the lower image, which was taken on January 2, the Wabash, Ohio, and Little Wabash Rivers are all swollen. By January 25, [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007025 ] the floods appeared to be receding. Daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/2007025 ] of the Midwest are available from the MODIS Rapid Response System. NASA images courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Haze off the U.S. East Coast
| Title |
Haze off the U.S. East Coast |
| Description |
Plumes of dingy gray haze collected off the east coast of the United States on July 19, 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Aqua [ http://aqua.nasa.gov ] satellite captured this image the same day. In this picture, the haze contrasts with nearby clouds, thanks to its darker color. While the clouds appear bright white, the haze is medium gray. The source of the haze is not apparent in this image. The U.S. Air Quality [ http://alg.umbc.edu/usaq/ ] blog at the University of Maryland, Baltimore County described smoke from Canadian fires entering the United States the day before. Smog from nearby U.S. cities, however, could also be the culprit. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. The Rapid Response Team provides daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA4/ ] of this region. |
|
Haze off the United States E
| Title |
Haze off the United States East Coast |
| Description |
Plumes of haze blew off the east coast of the United States and over the Atlantic Ocean in late June 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Aqua [ http://aqua.nasa.gov ] satellite took these pictures on June 23, 2007 (top), and June 24, 2007 (bottom). In these images, the haze appears as a blue-gray blur sweeping out over the ocean. While the plume of haze extends well to the south in the June 23 image, it follows a narrower path in the June 24 image. The haze plumes coincided with some air quality advisories for the Carolinas. According to the U.S. Environmental Protection Agency's AirNOW [ http://airnow.gov/ ] Website, both North and South Carolina experienced ozone levels in the moderate range on June 23 and 24. Under that category, "unusually sensitive people should consider limiting prolonged outdoor exertion." Besides plumes of haze, these satellite images show intermittent cloud cover in the region, as well as sunglint. Sunglint results from sunlight bouncing off the water's surface and into the satellite sensor. In the June 23 image, the sunglint is especially bright near the bottom right corner. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. The Rapid Response Team provides daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA8 ] of this region. |
|
Haze off the United States E
| Title |
Haze off the United States East Coast |
| Description |
Plumes of haze blew off the east coast of the United States and over the Atlantic Ocean in late June 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Aqua [ http://aqua.nasa.gov ] satellite took these pictures on June 23, 2007 (top), and June 24, 2007 (bottom). In these images, the haze appears as a blue-gray blur sweeping out over the ocean. While the plume of haze extends well to the south in the June 23 image, it follows a narrower path in the June 24 image. The haze plumes coincided with some air quality advisories for the Carolinas. According to the U.S. Environmental Protection Agency's AirNOW [ http://airnow.gov/ ] Website, both North and South Carolina experienced ozone levels in the moderate range on June 23 and 24. Under that category, "unusually sensitive people should consider limiting prolonged outdoor exertion." Besides plumes of haze, these satellite images show intermittent cloud cover in the region, as well as sunglint. Sunglint results from sunlight bouncing off the water's surface and into the satellite sensor. In the June 23 image, the sunglint is especially bright near the bottom right corner. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. The Rapid Response Team provides daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA8 ] of this region. |
|
Haze off the United States E
| Title |
Haze off the United States East Coast |
| Description |
Haze collected off the coasts of South Carolina, Georgia, and Florida on August 6, 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov/ ] flying on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured this image the same day. In this image, the haze appears as a blue-gray blur extending toward the Atlantic Ocean. Over land, the haze appears especially thick over Georgia. Although this image shows some wildfires, marked by red dots, the haze likely results from fires farther away, in the U.S. Northwest. [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14433 ] An August 6, 2007, posting on the U.S. Air Quality [ http://alg.umbc.edu/usaq/ ] (Smog Blog) at the University of Maryland, Baltimore County, described poor air quality along the U.S. East Coast, and provided a map of aerosol optical depth measured by Geostationary Operational Environmental Satellites (GOES). Aerosol optical depth indicates how much sunlight is intercepted by tiny suspended particles of solid or liquid in the air column. In the same area where this haze appears, GOES showed high readings, confirming the presence of aerosols. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. |
|
Haze over India
| Title |
Haze over India |
| Description |
Haze collected over northern India, near the border with Nepal, on October 15, 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Aqua [ http://aqua.nasa.gov ] satellite took this picture the same day. In this image, a dingy gray haze obscures the view of the land below. The haze hugs the border with Nepal in the northeast as well as taking a more southerly route in the west. The red dots are hotspots—temperature anomalies detected by the sensor—likely caused by fires. At the time MODIS acquired this picture, India's first biodiesel plant was beginning production, according to a report from The Times of India. The resulting "green" fuel, however, was planned for export to the United States and Europe. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. The Rapid Response Team provides daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?AERONET_Kanpur ] of this region. |
|
Haze over the Great Lakes
| Title |
Haze over the Great Lakes |
| Description |
Haze collected over the Great Lakes region at the end of July 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov/ ] flying on NASA's Terra [ http://terra.nasa.gov/ ] satellite captured this image on July 31. In this image, the haze appears as a blue-gray film, thickest over northern Michigan and Lake Superior. Haze also obscures the view of Lake Huron and Lake Erie. Although the exact source of the haze was uncertain, it could have resulted from fires in Canada [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14405 ] or the United States. [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14398 ] An August 1, 2007, posting on the U.S. Air Quality [ http://alg.umbc.edu/usaq/ ] (Smog Blog) at the University of Maryland, Baltimore County, traced a trajectory of smoke from fires in Oregon, Idaho, and Montana passing over the Great Lakes region and continuing southeast toward Baltimore. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. The Rapid Response Team provides daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?USA3/ ] of this region. |
|
Haze over Utah
| Title |
Haze over Utah |
| Description |
Haze clouded the skies over the southwestern United States, especially Utah, on September 8, 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite took this picture the same day. In this image, the pale colors dominating western Utah result partly from the light hues of the underlying ground surface, but a substantial gray-beige mass hangs in the atmosphere. The haze is thick enough to almost completely obscure the view of the Great Salt Lake. Although the exact origin of Utah's early September haze was not clear, it probably resulted from smoke released by fires to the north and west in Idaho and California. NASA image courtesy the MODIS Rapid Response Team, [ http://rapidfire.sci.gsfc.nasa.gov ] Goddard Space Flight Center |
|
Heatwave in the Western Unit
| Title |
Heatwave in the Western United States |
| Description |
The oppressive heat that crept over parts of the western United States during the first few days of July 2007 [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14380 ] took hold of the entire West during the week of July 4 through July 11. Deep red tones blanket every western state in this land surface temperature image, an indication that temperatures were warmer than in previous years. The image was made with data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) on NASA's Terra [ http://terra.nasa.gov/ ] satellite and shows temperatures recorded between July 4 and July 11, 2007, compared to the average of temperatures observed during the same period in 2000, 2001, and 2002. Areas that are warmer than during that three-year period are red, while cooler areas are blue. Triple-digit temperatures broke or matched records from Las Vegas, Nevada, to Great Falls, Montana, during this period. In this image, a cluster of red-black over eastern Washington, northern Idaho, and eastern Montana indicates that these regions experienced much warmer temperatures than in previous years. Western South Dakota (the Black Hills region) was also exceptionally warm. On the other end of the scale, Texas was much cooler than it had been in 2000, 2001, and 2002. Heavy rains pounded Texas on and off throughout this period, contributing to wide-spread flooding. [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14363 ] You can download a global KMZ file of Land Surface Temperature anomaly [ http://earthobservatory.nasa.gov/Newsroom/NewImages/Images/kansas_ast_2007187.kmz ] suitable for use with Google Earth. [ http://earth.google.com/ ] NASA image created by Jesse Allen, using data obtained courtesy of the MODIS Land Processes [ http://modis-land.gsfc.nasa.gov/ ] team. |
|
|