|
|
Color View of Eros' Saddle
| title |
Color View of Eros' Saddle |
| description |
Color imaging of Eros from the NEAR Shoemaker spacecraft has shown the asteroid's color variations are very subdued when compared to those of other planetary bodies, such as Mars. However, both the imager and the near-infrared spectrometer have detected discernible color differences between parts of the asteroid. One location on Eros with distinctive color is the eastern side of the 'saddle.' This color composite image of that region was taken April 2, 2000, from an orbital altitude of 201 kilometers (125 miles). In this false color representation, the red and green image planes were taken in different wavelengths of infrared light, and the blue image plane was taken in blue light. NEAR scientists interpret the bright and greenish-gray appearing regions near the rim of the saddle to represent relatively fresh exposures of subsurface soil. In contrast, the pinkish looking soil covering other areas is thought to have been modified by exposure to small impacts and the solar wind. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the firstspacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu [ http://near.jhuapl.edu ] for more details. |
|
Eros' Saddle
| title |
Eros' Saddle |
| date |
04.02.2000 |
| description |
Color imaging of Eros from the NEAR Shoemaker spacecraft shows the asteroid's color variations are very subdued when compared to those of other planetary bodies, such as Mars. However, both the imager and the near-infrared spectrometer have detected discernible color differences between parts of the asteroid. One location on Eros with distinctive color is the eastern side of the "saddle." This color composite image of that region was taken April 2, 2000, from an orbital altitude of 201 kilometers (125 miles). In this false color representation, the red and green image planes were taken in different wavelengths of infrared light, and the blue image plane was taken in blue light. NEAR scientists interpret the bright and greenish-gray appearing regions near the rim of the saddle to represent relatively fresh exposures of subsurface soil. In contrast, the pinkish looking soil covering other areas is thought to have been modified by exposure to small impacts and the solar wind. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. *Image Credit*: NASA |
|
Flying Over Asteroid Eros
| Title |
Flying Over Asteroid Eros |
| Explanation |
What would it look like to fly over an asteroid? Spacecraft NEAR Shoemaker [ http://near.jhuapl.edu/NEAR/Voyage/ ] in orbit around asteroid 433 Eros [ http://near.jhuapl.edu/NEAR/eros/sum.html ] found out earlier this month when it recorded its first fly-over sequence. The saddle region [ http://antwrp.gsfc.nasa.gov/apod/ap000214.html ] of the Sun-orbiting space-mountain appears to zip past the camera in this condensed hour-long time-lapse sequence [ http://near.jhuapl.edu/NEAR/iod/20000323/ ]. The spacecraft was orbiting about 200 kilometers above the asteroid [ http://www.seds.org/nineplanets/nineplanets/asteroids.html ]. Movies such as this are scientifically useful [ http://antwrp.gsfc.nasa.gov/apod/ap991108.html ] for discerning between regions that are naturally dark and regions that have their brightness dominated by shadows. The week before, a bright X-ray burst [ http://antwrp.gsfc.nasa.gov/apod/ap000327.html http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1999A%26A...347..684G ] from the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap981221.html ] allowed NEAR's X-ray spectrometer [ http://near.jhuapl.edu/NEAR/instruments/ ] to detect [ http://www.jhuapl.edu/public/pr/000313.htm ] the presence of several elements [ http://pearl1.lanl.gov/periodic/ ] on Eros' surface by their X-ray fluorescent [ http://www.scimedia.com/chem-ed/spec/atomic/afs.htm ] signatures. |
|
Flying Over Asteroid Eros' W
…
| Title |
Flying Over Asteroid Eros' West End |
| Explanation |
The robot spacecraft NEAR Shoemaker continues to orbit asteroid Eros. This condensed 40-minute long time-lapse sequence [ http://near.jhuapl.edu/NEAR/iod/20000324/ ] taken last month shows what it looks like to pass within 200 kilometers of Eros [ http://near.jhuapl.edu/eros/sum.html ]' west end. The north pole of the rotating mountain [ http://antwrp.gsfc.nasa.gov/apod/ap000327.html ] is toward the bottom of the picture. This month NEAR-Shoemaker closes [ http://near.jhuapl.edu/news/flash/000402.html ] to within 100 kilometers, and by the end of this month will orbit only 50 kilometers from the center of this 33-kilometer long asteroid [ http://www.seds.org/nineplanets/nineplanets/asteroids.html ]. One reason for moving in so close is to determine if 433 Eros has a magnetic field [ http://near.jhuapl.edu/news/sci_updates/000407.html ]. NEAR Shoemaker, launched in 1996, is run [ http://near.jhuapl.edu/intro/faq.html ] by a computer similar to a PC released 15 years ago (12 MHz, 256K). |
|
Eros Craters And Boulders
| Title |
Eros Craters And Boulders |
| Explanation |
From a delicate [ http://near.jhuapl.edu/NEAR/news/sci_updates/ 000505.html ] orbit around asteroid 433 Eros, the NEAR Shoemaker spacecraft's camera has now imaged the entire surface of the small [ http://pdssbn.astro.umd.edu:80/sbnhtml/ ] oddly-shaped [ http://antwrp.gsfc.nasa.gov/apod/ap000224.html ] world at least once. Recorded on July 7th from a distance of 50 kilometers, this dramatic view [ http://near.jhuapl.edu/NEAR/iod/20000718/index.html ] is about 1.8 kilometers across. It shows the walls and rims of two large overlapping impact [ http://antwrp.gsfc.nasa.gov/apod/ap990711.html ] craters on the horizon. Massive boulders which may be debris from the impacts are perched along the crater edges. The prominent boulder [ http://antwrp.gsfc.nasa.gov/apod/ap970905.html ] on the horizon near picture center is about 40 meters long. In fact, the NEAR mission to Eros [ http://www.boulder.swri.edu/~cchapman/finderos.html ] has shown that along with craters and boulders, grooves and ridges are also [ http://www.msss.com/mars_images/moc/9_11_98_phobos_rel/ index.html ] common on the asteroid's [ http://nssdc.gsfc.nasa.gov/planetary/planets/ asteroidpage.html ] surface. While the craters are clearly of impact origin, puzzles about [ http://near.jhuapl.edu/NEAR/news/sci_updates/ 00jul19.html ] the other surface features still remain. On July 13, controllers fired the spacecraft thrusters and moved NEAR Shoemaker [ http://near.jhuapl.edu/NEAR/news/flash/00jul14_1.html ] to an even closer [ http://huey.jpl.nasa.gov/~spravdo/neat.html ] 35 kilometer orbit to enable higher resolution surface studies. |
|
22 Miles From Eros
| Title |
22 Miles From Eros |
| Explanation |
Last month the NEAR Shoemaker [ http://near.jhuapl.edu/NEAR/Education/model.html ] spacecraft swooped closer [ http://near.jhuapl.edu/NEAR/news/flash/00jul07_1.html ] to Eros, orbiting only 22 miles (36 kilometers) from [ http://antwrp.gsfc.nasa.gov/apod/ap980919.html ] the center of the asteroid. These two images taken on July 19 (left) [ http://near.jhuapl.edu/NEAR/iod/20000801/index.html ] and July 24 (right) [ http://near.jhuapl.edu/NEAR/iod/20000731/index.html ] reveal the diminutive world's [ http://antwrp.gsfc.nasa.gov/apod/ap000224.html ] pocked and mottled surface in amazing detail, showing features as small as 19 feet (6 meters) across. Eros is thought to be a primordial [ http://www.jhuapl.edu/public/pr/000530.htm ], undifferentiated asteroid [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/ asteroids.html ] based on X-ray and gamma-ray [ http://near.jhuapl.edu/news/sci_updates/00jun20.html ] studies of its surface composition. In the left picture, its surface layer or regolith [ http://near.jhuapl.edu/news/sci_updates/00jul05.html ] is seen to be laced with bright and dark regions while in the right hand image dark regolith appears [ http://near.jhuapl.edu/NEAR/iod/20000707/index.html ] to have filled in some crater floors. The left and right images span an area about 2,600 feet (800 meters) and 3,000 ft (900 meters) wide respectively. On July 31, NEAR Shoemaker returned to [ http://near.jhuapl.edu/news/flash/00aug01_1.html ] its familiar 31 mile (50 kilometer) orbit, circling [ http://www.jpl.nasa.gov/basics/orbits.htm#orbits ] Eros serenely at about 6 miles per hour. |
|
Eros At Sunset
| Title |
Eros At Sunset |
| Explanation |
Gleaming in the rays of the setting sun, boulders litter the rugged surface of asteroid 433 Eros [ http://near.jhuapl.edu/eros/ ]. The brightest boulder, at the edge of the large, shadowy crater near this picture's bottom center, is about 30 meters (100 feet) across. In orbit around Eros since February 2000, the NEAR Shoemaker [ http://near.jhuapl.edu/NEAR/ ] spacecraft's camera recorded the dramatic view [ http://near.jhuapl.edu/NEAR/iod/20000821/index.html ] earlier this month from an altitude of about 50 kilometers. Eros itself orbits [ http://www.fwkc.com/encyclopedia/low/articles/o/ o018000416f.html ] the Sun with a perihelion [ http://imagine.gsfc.nasa.gov/docs/ dictionary.html#perihelion ] of 1.13 Astronomical Units [ http://imagine.gsfc.nasa.gov/docs/ask_astro/ answers/980122b.html ] (AU) and aphelion [ http://imagine.gsfc.nasa.gov/docs/ dictionary.html#aphelion ] of 1.78 AU. Part of a class of near-Earth asteroids [ http://neo.jpl.nasa.gov/neo.html ], it spends much of its time between the orbits of Mars (at 1.5 AU) and Earth (at 1 AU) ... but it wasn't always that way. Eros and other near-Earth asteroids [ http://neo.planetary.org/ABCsOfNEOs/index.html ] originally orbited in the main asteroid belt [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/ asteroids.html ], between Jupiter [ http://galileo.jpl.nasa.gov/jupiter/jupiter.html ] and Mars [ http://nssdc.gsfc.nasa.gov/planetary/factsheet/ marsfact.html ]. Over time, the gravitational influence of Jupiter and other planets perturbed their orbits sending them on trajectories closer [ http://antwrp.gsfc.nasa.gov/apod/ap000226.html ] to Earth. |
|
The Map Of Eros
| Title |
The Map Of Eros |
| Explanation |
This map [ http://near.jhuapl.edu/iod/20001024a/index.html ] of Eros was constructed from a mosaic of images recorded by the NEAR Shoemaker spacecraft, currently orbiting the 40 x 14 x 14 kilometer asteroid. A simple cylindrical projection [ http://www.colorado.edu/geography/gcraft/notes/mapproj/ mapproj.html ] of an irregularly shaped world [ http://near.jhuapl.edu/NEAR/iod/20000214b/index.html ], the map's individual images don't always match up at the edges. Shown here, place names have been proposed [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/nomen/ nomen.html ] to describe the geography of Eros [ http://antwrp.gsfc.nasa.gov/apod/ap000224.html ] with a fitting theme, though. They are based on romantic figures in the history and literature of the cultures of planet Earth. The largest feature, Himeros [ http://near.jhuapl.edu/iod/20001025/index.html ], is a depression about 10 kilometers wide. In Greek mythology [ http://www.pantheon.org/mythica/areas/greek/ ], Himeros was an attendant of Eros and the personification of the longing of love. Today, after safely surveying Eros [ http://www.jhuapl.edu/public/pr/001024.htm ] for the past eight months, NEAR Shoemaker is scheduled to make a daring close approach [ http://www.jhuapl.edu/public/pr/001023.htm ] to the asteroid, briefly flying to within about 6 kilometers of its surface. Images returned [ http://near.jhuapl.edu/ ] from that distance are expected to show features less than 1 meter across. |
|
Close To Eros
| Title |
Close To Eros |
| Explanation |
Scroll right and fly close over asteroid [ http://www.edunet.ie/stlaur/asteroid.html ] Eros! This long mosaic [ http://near.jhuapl.edu/iod/20001026d/ ] was constructed of images returned yesterday by the NEAR [ http://near.jhuapl.edu/NEAR/ ] Shoemaker spacecraft as it orbited to within 6.4 kilometers of a spot in the southern hemisphere of the rotating asteroid's surface. That distance (about 21,000 feet) is less than the cruising altitude of most commercial airline flights. The digital images show that while many regions appear smooth with craters filled in by an accumulation of loose regolith [ http://antwrp.gsfc.nasa.gov/apod/ap000829.html ], much of Eros' surface is littered with rocks and boulders. The large boulder [ http://near.jhuapl.edu/iod/20001026c/ ] glinting in the sunlight at the far left, just above the center of the mosaic, spans approximately 25 meters. In the high-resolution view, the smallest rocks [ http://near.jhuapl.edu/NEAR/iod/20001026b/ ] visible are roughly human-sized at about 1.4 meters (5 feet) across. The car-sized [ http://near.jhuapl.edu/old/Education/model.html ] Near Shoemaker spacecraft is now on its way [ http://near.jhuapl.edu/NEAR/news/flash/00oct26_2.html ] to a higher, more stable orbit about 200 kilometers above asteroid Eros [ http://near.jhuapl.edu/eros/sum.html ]. |
|
Stereo Eros
| Title |
Stereo Eros |
| Explanation |
Get out your red/blue glasses [ http://photojournal.jpl.nasa.gov/Help/VendorList.html#Glasses ] and float next to asteroid 433 Eros [ http://neo.jpl.nasa.gov/cgi-bin/db?name=433 ], now over 220 million kilometers away! Orbiting the Sun once every 1.8 earth-years, asteroid Eros is [ http://near.jhuapl.edu/eros/history/eros_useful.html ] a diminutive 40 x 14 x 14 kilometer world of undulating horizons, craters, boulders [ http://antwrp.gsfc.nasa.gov/apod/ap000721.html ] and valleys. Its unsettling scale and bizarre shape are emphasized in this picture [ http://photojournal.jpl.nasa.gov/catalog/PIA02471 ] - a mosaic of images from the NEAR Shoemaker [ http://photojournal.jpl.nasa.gov/target/ Other?subselect=Spacecraft%3ANEAR+Shoemaker%3A ] spacecraft processed to yield a stereo anaglyphic [ http://faxmentis.org/html/ana-howto.html ] view. Along with dramatic [ http://en.wikipedia.org/wiki/Chiaroscuro#Gallery ] chiaroscuro [ http://studiochalkboard.evansville.edu/s-chiaro.html ], NEAR's 3-D imaging provided important measurements of the asteroid's landforms and structures, and clues to the origin of this city-sized chunk of solar system [ http://space.jpl.nasa.gov/ ]. The smallest features visible here are about 30 meters across. After spending a year in orbit around Eros, the historic Near Shoemaker spacecraft made the first ever landing on an asteroid's surface [ http://antwrp.gsfc.nasa.gov/apod/ap010824.html ] February 12, 2001. |
|
Survivor: NEAR Shoemaker On
…
| Title |
Survivor: NEAR Shoemaker On Asteroid Eros |
| Explanation |
Not part of a television game series, the NEAR Shoemaker spacecraft survived [ http://www.jhuapl.edu/public/pr/010228.htm ] its unprecedented landing on an asteroid [ http://www.nineplanets.org/asteroids.html ] last month. As suggested in the illustration inset above [ http://near.jhuapl.edu/NEAR/iod/20010209/index.html ], the car-sized probe likely rests gently on the tips of its solar panels having touched down under the influence of asteroid Eros' feeble gravity. Fortunately, the spacecraft's solar panels were bathed in sunlight and able to power NEAR's gamma-ray spectrometer [ http://near.jhuapl.edu/NEAR/instruments/ XGRS/index.html ]. Perched on the asteroid, this instrument can determine the composition of Eros to a depth of about 10 centimeters with unanticipated accuracy by measuring the gamma-ray signatures [ http://science.msfc.nasa.gov/headlines/y2001/ast27feb_2.htm ] of the atomic nuclei present. The data returned [ http://near.jhuapl.edu/NEAR/iod/20010301/ ] from the surface of Eros are plotted above and show clearly features corresponding to Iron, Oxygen, Silicon, and Potassium in the asteroid's regolith [ http://antwrp.gsfc.nasa.gov/apod/ap000829.html ]. Also briefly operating on Eros, NEAR's magnetometer [ http://near.jhuapl.edu/NEAR/instruments/MAG/index.html ] has indicated that no surface magnetic field [ http://www-spof.gsfc.nasa.gov/Education/wmfield.html ] is discernible. Now turned off [ http://near.jhuapl.edu/NEAR/Reports/WeeklyStatus/ 2001-03-02.txt ], NEAR Shoemaker could remain preserved in its present location, the vicinity of the huge, saddle-shaped feature dubbed Himeros [ http://antwrp.gsfc.nasa.gov/apod/ap001026.html ], for billions of years. But, as the asteroid orbits [ http://science.nasa.gov/headlines/y2000/ ast21jun_1_ada.htm ], the spacecraft's solar panels will be repeatedly turned toward the Sun ... offering the possibility of reawakening this survivor [ http://antwrp.gsfc.nasa.gov/apod/ap010213.html ]. |
|
Stereo Eros
| Title |
Stereo Eros |
| Explanation |
Get out your red/blue glasses [ http://mpfwww.jpl.nasa.gov/MPF/mpf/glasses.html ] and float next to asteroid 433 Eros [ http://neo.jpl.nasa.gov/cgi-bin/db?name=433 ], 170 million kilometers away! Orbiting the Sun once every 1.8 earth-years, asteroid Eros is [ http://near.jhuapl.edu/eros/history/eros_useful.html ] a diminutive 40 x 14 x 14 kilometer world of undulating horizons, craters, boulders [ http://antwrp.gsfc.nasa.gov/apod/ap000721.html ] and valleys. Its unsettling scale and bizarre shape are emphasized in this picture [ http://near.jhuapl.edu/NEAR/iod/20000218/index.html ] - a mosaic of images from the NEAR Shoemaker spacecraft [ http://near.jhuapl.edu/NEAR/news/flash/02dec12_1.html ] processed to yield a stereo anaglyphic [ http://near.jhuapl.edu/NEAR/3_d.html ] view. Along with dramatic [ http://www.artofcolour.com/chiaroscuro/chiaroscuro-image-files/ st-matthew.jpg ] chiaroscuro [ http://www2.evansville.edu/studiochalkboard/ s-chiaro.html ], NEAR's 3-D imaging provided important measurements of the asteroid's landforms and structures, and clues to the origin [ http://near.jhuapl.edu/NEAR/Voyage/1.html ] of this city-sized chunk of solar system [ http://space.jpl.nasa.gov/ ]. The smallest features visible here are about 30 meters across. After spending a year in orbit around Eros, the historic Near Shoemaker spacecraft made the first ever landing on an asteroid's surface [ http://antwrp.gsfc.nasa.gov/apod/ap010824.html ] February 12, 2001. |
|
Location of the NEAR Shoemak
…
| Title |
Location of the NEAR Shoemaker Landing Site |
| Description |
The location of NEAR Shoemaker's planned landing site is shown in this image mosaic taken on December 3, 2000, from an orbital altitude of 200 kilometers (124 miles). In this view, south is to the top and the terminator (the imaginary line dividing day from night) lies near the equator. The landing site (at the tip of the arrow) is near the boundary of two distinctly different provinces, both of which the spacecraft will photograph as it descends. To the south and east (above and to the left) lies older, cratered terrain, while to the north (down) is the saddle-shaped feature Himeros, whose lesser density of superposed craters indicates relatively recent resurfacing by geologic processes. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
02.12.2001 |
|
NEAR Shoemaker's Path
| Title |
NEAR Shoemaker's Path |
| Description |
This plot shows NEAR Shoemaker's projected path from orbit to the surface of Eros on Feb. 12. Viewed from the sun, Eros is moving in a clockwise direction as it spins on its axis, while the spacecraft moves counterclockwise in a circular orbit 35 kilometers (22 miles) from the asteroid's center. The pair will be about 316 million kilometers (196 million miles) from Earth. NEAR Shoemaker will de-orbit with a short engine burn at 10:31 a.m. EST, about 4 1/2 hours before it's scheduled to reach the surface. The final leg of the controlled descent begins with the spacecraft about 5 kilometers (3 miles) above Eros, it will then execute an unprecedented series of four engine burns designed to slow its descent from about 20 mph to about 5 mph. NEAR Shoemaker is expected to touch down in an area bordering Himeros, the asteroid's distinctive saddle-shaped depression, after providing the highest-resolution images ever taken of Eros' boulder-strewn, cratered terrain. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
02.08.2001 |
|
Boulderado
| Title |
Boulderado |
| Description |
One of the most recognizable surface features on Eros is the boulder-filled, concave depression at the southwestern edge of the saddle-shaped Himeros. When it was first glimpsed early in NEAR Shoemaker's orbital mission the area was informally tagged "Boulderado. |
| Date |
02.06.2001 |
|
Eros' Battered Surface
| Title |
Eros' Battered Surface |
| Description |
NEAR Shoemaker captured this image of Eros on November 28, 2000, while taking a color flyover movie from 193 kilometers (120 miles) away. This particular view simultaneously shows several key indicators of the battering Eros' surface has sustained over the eons. Most obvious are the countless craters, some barely big enough for the camera to see. Less obvious are the signs of a layer of fragmental debris, or regolith, blanketing the surface. Among them are the rounded horizon, the boulders visible in the distance, and the bright patches of exposed subsurface material on steep slopes. This scene is approximately 6.6 kilometers (4.1 miles) across. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
12.06.2000 |
|
Final Eros Images: Last, Clo
…
| Title |
Final Eros Images: Last, Closest Image of Eros |
| Description |
This is the last image of asteroid 433 Eros received from NEAR Shoemaker. Taken from a range of 120 meters (394 feet), it measures 6 meters (20 feet) across. What we can see of the rock at the top of image measures 4 meters (12 feet) across. The streaky lines at the bottom indicate loss of signal as the spacecraft touched down on the asteroid during transmission of this image. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
02.12.2001 |
|
Final Eros Images: Range 1,1
…
| Title |
Final Eros Images: Range 1,150 meters (3,773 feet) |
| Description |
NEAR Shoemaker took this image of asteroid 433 Eros from a range of 1,150 meters (3,773 feet). The image is 54 meters (177 feet) across. The large rock at lower left is 7.4 meters (24 feet) across. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
02.12.2001 |
|
Final Eros Images: Range 250
…
| Title |
Final Eros Images: Range 250 meters (820 feet) |
| Description |
NEAR Shoemaker's image of asteroid 433 Eros taken from a range of 250 meters (820 feet). The image is 12 meters (39 feet) across. The cluster of rocks at the upper right measures 1.4 meters (5 feet) across. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
02.12.2001 |
|
Final Eros Images: Range 700
…
| Title |
Final Eros Images: Range 700 meters (2,300 feet) |
| Description |
NEAR Shoemaker's image of asteroid 433 Eros taken from a range of 700 meters (2,300 feet). The image is 33 meters (108 feet) across. The large, oblong rock casting a big shadow measures 7.4 meters (24 feet) across. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
02.12.2001 |
|
The Environs of NEAR Shoemak
…
| Title |
The Environs of NEAR Shoemaker's Landing Site |
| Description |
This image mosaic of Eros' southern hemisphere, taken by NEAR Shoemaker on November 30, 2000, offers a long-distance look at the cratered terrain south of where the spacecraft will touch down on February 12, 2001. In this view, south is to the top and the landing site itself is just into the shadows, slightly left of center. The length of the asteroid is 33 kilometers (21 miles). Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
02.07.2001 |
|
Two Very Different Asteroids
| Title |
Two Very Different Asteroids |
| Description |
The NEAR Shoemaker spacecraft has scored two important firsts in the exploration of asteroids: it's the first to orbit an asteroid, Eros, and the first to encounter a denizen of the outer reaches of the asteroid belt, the C-type asteroid Mathilde. In a scheme that reflects how they have historically been a topic for astronomy, not geology, asteroids are classified into groups based on their colors as observed through telescopes. The two major classes of asteroids are called S-types and C-types. S-types, whose colors are consistent with "stony" or rocky compositions, prevail among asteroids that orbit closer to the Sun than the mid-point of the asteroid belt. Eros and the two asteroids encountered briefly by the Galileo spacecraft on its way to Jupiter -- Gaspra and Ida -- are all S-types. C-types like Mathilde have a dark gray color consistent with a "carbonaceous" composition, rich in carbon compounds and other dark materials. They prevail in the outer part of the asteroid belt. In this montage, Mathilde (at left) and Eros (at right) are shown at the same scale, as they were imaged by NEAR Shoemaker from about 1,800 kilometers (1,116 miles) on June 27, 1997, and February 12, 2000, respectively. Mathilde is 56 kilometers (35 miles) across, and Eros is 33 kilometers (21 miles) long and 13 kilometers (8 miles) wide. However, Mathilde's brightness is greatly exaggerated for viewing purposes -- it's actually six times darker than Eros, with about the same reflectivity as soot! Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
03.30.2000 |
|
Landmarks at NEAR Shoemaker'
…
| Title |
Landmarks at NEAR Shoemaker's Touchdown Site |
| Description |
This map projection of NEAR Shoemaker images shows locations and sizes of landmarks surrounding the spacecraft's planned landing site. Diameters of craters are shown in red, and diameters of boulders are shown in yellow. Diameters are given in units of meters (1 meter is about 3.3 feet). Coordinates along the left side of the map are degrees south latitude and coordinates along the bottom are degrees west longitude. The six yellow "footprint" boxes represent approximate image size at 500,1,000, 1,500, 2,000, 2,500 and 3,000 meters above the surface during descent. The spacecraft will take pictures continuously between each spot. The arrow marks the estimated touchdown site. Mosaic made from images taken January 25, 2001, from an altitude of about 25 kilometers (16 miles). Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
| Date |
02.12.2001 |
|
Eros' Bland Butterscotch Col
…
PIA02475
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros' Bland Butterscotch Colors |
| Original Caption Released with Image |
These color images of Eros was acquired by NEAR on February 12, 2000, at a range of 1800 kilometers (1100 miles) during the final approach imaging sequence prior to orbit insertion. A five and one-half hour long sequence of images covering visible and infrared wavelengths was taken at that time, to provide a global overview of the color and spectral properties of the asteroid. The images show approximately the color that Eros would appear to the unaided human eye. Eros' subtle butterscotch hue at visible wavelengths is nearly uniform across the surface. Two days after these images were taken, mapping by NEAR's infrared spectrometer showed that Eros exhibits a great deal more variety at longer wavelengths. These variations could be due to differences in texture or composition of the surface. Both NEAR's multispectral imager and infrared spectrometer will be used extensively during the month of March to map Eros' color and spectral properties from an altitude of 200 kilometers (120 miles). The images to be returned will show details as small as 20 meters (68 feet) across, providing a new perspective on the asteroid's many fascinating landforms discovered so far by NEAR. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Eros' Global Morphology
PIA02473
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros' Global Morphology |
| Original Caption Released with Image |
On 12 February, 2000, the NEAR spacecraft obtained a sequence of 780 images of Eros from a range of about 1800 km (1100 miles). This sequence covered one complete revolution of the asteroid at 0.5 degree intervals. In these views of opposite hemispheres of the asteroid, groups of images slightly apart in time were digitally processed to bring out local details. The processed data showing Eros from slightly different perspectives can then be combined as anaglyphs or stereo pairs. The processing of the data highlights the topography of small-scale features, but makes the gross shape of the asteroid appear flattened. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Inside Eros' Giant Gouge
PIA02469
Sol (our sun)
Multi-Spectral Imager
| Title |
Inside Eros' Giant Gouge |
| Original Caption Released with Image |
This picture was taken from NEAR on February 15, 2000, while the spacecraft was passing directly over the large gouge that creates Eros's characteristic peanut shape. It is a mosaic of individual images showing features as small as 120 feet (35 meters) across. Although most of the asteroid is in shadow, we are able to see inside the gouge. Many narrow parallel troughs closely follow the shape of the gouge. Although they appear curvilinear from this view, they are most likely oriented parallel to the length of the asteroid. The strong lighting contrast along the terminator (the line separating day from night on Eros) makes it easy to see that most of the surface is saturated with impact craters. Inside the gouge, however, only smaller craters are present, indicating that the area within the gouge is younger than the surface along the terminator. This implies that the event that caused the gouge must have happened more recently than the formation of the rest of the surface of Eros. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Eros: The first look from or
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PIA02465
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros: The first look from orbit |
| Original Caption Released with Image |
In the first hours after NEAR's insertion into Eros orbit (February 14, 2000), the spacecraft's camera took these images from a range of 210 miles (330 km) above the surface. The many craters visible serve as landmarks for navigating the spacecraft. Mission operators observe such features from different angles, and use triangulation to calculate NEAR's position relative to the surface of Eros. The changes in position over time help to plot NEAR's course in orbit. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Eros Image Mosaic, looking n
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PIA02472
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros Image Mosaic, looking north |
| Original Caption Released with Image |
This image mosaic of Eros was taken by the NEAR spacecraft on Feb. 18, 2000 from a range of 224 miles (361 kilometers). The smallest detail visible on the surface is about 115 feet (35 meters) across. At the time the spacecraft was over the shadowed southern hemisphere, looking north at a crescent Eros. Although this view of Eros is similar to others that have been returned, the coverage at different illumination and viewing geometries provides important information on the shapes of landforms. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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NEAR's first whole-Eros mosa
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PIA02467
Sol (our sun)
Multi-Spectral Imager
| Title |
NEAR's first whole-Eros mosaic from orbit |
| Original Caption Released with Image |
This picture of Eros, the first of an asteroid taken from an orbiting spacecraft, is a mosaic of four images obtained by NEAR on February 14, 2000, immediately after the spacecraft's insertion into orbit. We are looking down over the north pole of Eros at one of the largest craters on the surface, which measures 4 miles (6 kilometers) across. Inside the crater walls are subtle variations in brightness that hint at some layering of the rock in which the crater formed. Narrow grooves that run parallel to the long axis of Eros cut through the southeastern part of the crater rim. A house-sized boulder is present near the floor of the crater, it appears to have rolled down the bowl-shaped crater wall. A large number of boulders is also present on other parts of the asteroid's surface. The surface of the asteroid is heavily cratered, indicating that Eros is relatively old. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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NEAR Approach to Eros - 12 p
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PIA02463
Sol (our sun)
Multi-Spectral Imager
| Title |
NEAR Approach to Eros - 12 panel rotation sequence |
| Original Caption Released with Image |
On February 12, two days before NEAR's insertion into orbit around Eros, during a five-hour time span the spacecraft's Multispectral Imager recorded these pictures of the asteroid spinning on its axis. This view, looking down toward the rocky body's north pole, is generally similar to sequences taken on February 6, 10, and 11. But the spacecraft was much closer to Eros (about 1,800 kilometers or a little over 1,100 miles), so the pictures are much sharper. Features as small as a 590 feet (180 meters) wide can be seen. The most prominent, sharp-rimmed impact crater is on the opposite side of Eros from a huge, hollowed-out gouge, which may also have been caused by an impact. Between these features, and towards the ends of the "fat banana" shape of Eros, the asteroid's surface is covered with smaller craters. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Mosaic of Mathilde
PIA02477
Sol (our sun)
Multi-Spectral Imager
| Title |
Mosaic of Mathilde |
| Original Caption Released with Image |
This image mosaic of asteroid 253 Mathilde is constructed from four images acquired by the NEAR spacecraft on June 27, 1997. This was taken from a distance of 2,400 km (1,500 miles). Sunlight is coming from the upper right. The part of the asteroid shown is about 59 by 47 km (36 by 29 miles) across. Details as small as 380 meters (1,250 feet) can be discerned. The surface exhibits many large craters, including the deeply shadowed one at the center, which is estimated to be more than 10 kilometers (6 miles) deep. The shadowed, wedge-shaped feature at the lower right is another large crater viewed obliquely. The angular shape of the upper left limb of the asteroid results from the rim of a third large crater viewed edge-on. The bright mountainous feature at the far left may be the rim of a fourth large crater emerging from the shadow. The angular shape is believed to result from a violent history of impacts. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Abundance of Very Large Impa
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PIA02478
Sol (our sun)
Multi-Spectral Imager
| Title |
Abundance of Very Large Impact Craters on Mathilde |
| Original Caption Released with Image |
This view of 253 Mathilde, taken from a distance of about 1,200 km (748 miles), was acquired shortly after the NEAR spacecraft's closest approach to the asteroid. In this image, the asteroid has been rotated so that the illumination appears to come from the upper left. This portion of Mathilde shows numerous impact craters, ranging from over 30 km to less than 0.5 km (18.. 0.3 miles) in diameter. Raised crater rims suggest that some of the material ejected from these craters traveled only short distances before falling back to the surface, straight sections of some crater rims indicate the influence of large faults or fractures on crater formation. The number of craters as a function of size, and the number of each size within the visible area, are similar to values seen on asteroid 243 Ida, viewed by the Galileo spacecraft in 1993. A major difference between Ida and Mathilde appears to be the abundance of very large craters: Mathilde has at least 5 craters larger than 20 km in diameter on the roughly 60% of the body viewed during the encounter. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Over Eros' Horizon
PIA02468
Sol (our sun)
Multi-Spectral Imager
| Title |
Over Eros' Horizon |
| Original Caption Released with Image |
This incredible picture of Eros, taken on February 14, 2000, shows the view looking from one end of the asteroid across the gouge on its underside and toward the opposite end. In this mosaic, constructed from two images taken after the NEAR spacecraft was inserted into orbit, features as small as 120 feet (35 meters) across can be seen. House-sized boulders are present in several places, one lies on the edge of the giant crater separating the two ends of the asteroid. A bright patch is visible on the asteroid in the top left-hand part of this image, and shallow troughs can be see just below this patch. The troughs run parallel to the asteroid's long dimension. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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NEAR Historic First Image fr
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PIA02464
Sol (our sun)
Multi-Spectral Imager
| Title |
NEAR Historic First Image from Eros Orbit |
| Original Caption Released with Image |
February 14, 2000, at 10:33 AM EST the NEAR spacecraft was successfully inserted into orbit around 433 Eros, becoming the first artificial satellite of an asteroid. Just over an hour later, NEAR pointed its camera at the asteroid and took this picture from a range of 210 miles (330 km) above the surface. Mission navigators and operators will use this image and others to be taken later to triangulate on landmarks on the asteroid's surface, precisely measuring position of the spacecraft to plot NEAR's course. Features as small as a 100 feet (30 meters) across can be seen. This view shows the 3-mile (5-kilometer) impact crater which the spacecraft has spied for over a week during its approach. The two smaller craters superimposed on its rim are each about 1.2 miles (2 kilometers) across. An enormous boulder a full 170 feet (50 meters) in size sits on the large crater's floor. Other key features of the surface are shallow subsurface layering exposed near the tops of crater walls, and shallow grooves crossing the surface and cutting the crater's rim. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Eros in color
PIA02470
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros in color |
| Original Caption Released with Image |
This color image of Eros was acquired by NEAR's multispectral imager on February 12, 2000, at a range of 1100 miles (1800 kilometers). It is part of the final approach imaging sequence prior to orbit insertion and is intended to map the color properties of Eros across all of the illuminated surface. The image shows approximately the color that Eros would appear to the unaided human eye. Its subtle butterscotch hue is typical of a wide variety of minerals thought to be the major components of asteroids like Eros. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Eros' Eastern and Western He
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PIA02474
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros' Eastern and Western Hemispheres |
| Original Caption Released with Image |
On February 23, 2000, the NEAR spacecraft obtained a sequence of image mosaics showing Eros' surface as the asteroid rotated under the spacecraft. At that time the range to the surface was approximately 355 kilometers (220 miles). These two mosaics, part of that sequence, show the stark beauty of the two opposite hemispheres. The smallest detail visible is 35 meters (120 feet) across. The top mosaic shows wavy brightness banding exposed in the interior walls of the saddle. In the bottom mosaic, similar banding is visible in one of the craters near the limb at left. To the right, the angle of the illumination accentuates the quasi-linear troughs near the terminator. Successful firing of NEAR's thrusters yesterday, February 24, placed the spacecraft on course for insertion into the next lower orbit, at a 200 kilometer (120 mile) altitude. Images from that orbit, commencing in early March, will have nearly twice the spatial resolution of data returned so far. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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NEAR Road to Eros
PIA02462
Sol (our sun)
Multi-Spectral Imager
| Title |
NEAR Road to Eros |
| Original Caption Released with Image |
This montage shows a selection of images of the asteroid 433 Eros that were acquired from the NEAR spacecraft over three weeks from January 22 through February 12, 2000, as the spacecraft's distance from its target shrank from 18,000 to 1260 miles (29,000 to 2025 km). As the spacecraft closed in on its target, the resolution of the images increased from 1.7 to 0.12 miles (2.8 to 0.19 km) per pixel. At 20x8x8 miles in size (33x13x13 kilometers), Eros is the second largest near-Earth asteroid and spins on its axis once every 5 hours, 16 minutes. During the early stages of NEAR's approach, Eros appeared as a small blob only a few pixels across. The apparent size of Eros and the resolution of the pictures increased continuously, at first only slowly and later dramatically day by day until, on February 9, the level of detail visible exceeded that during NEAR's first flyby of Eros on December 23, 1998. In the last images shown here, details of Eros's surface have become visible. Heavy cratering has pockmarked the irregular asteroid's surface. One side is dominated by a scallop-rimmed gouge, and the opposite side by a conspicuous, raised-rimmed crater. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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First NEAR image of Mathilde
PIA02476
Sol (our sun)
Multi-Spectral Imager
| Title |
First NEAR image of Mathilde |
| Original Caption Released with Image |
This first image of asteroid 253 Mathilde, returned by the NEAR spacecraft just before 10:00 AM EDT on June 27, 1997, was taken from a distance of 1800 kilometers (1120 miles). Sunlight is coming from the upper right. The part of the asteroid shown is about 59 kilometers (36 miles) across, and the scale is approximately 230 meters (780 feet) per pixel. The surface is heavily cratered, and the large shadowed area on the left may be a single impact gouge well over 10 kilometers (6 miles) deep. The angular form of the edge of the shadowed area suggests that large impacts may have spalled large pieces off the asteroid. This asteroid is very dark, reflecting only about 4% of the light falling on it, but was imaged easily by the sensitive NEAR multispectral camera Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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NEAR Approach to Eros
PIA02461
Sol (our sun)
Multi-Spectral Imager
| Title |
NEAR Approach to Eros |
| Original Caption Released with Image |
Approximately one day after its first rendezvous burn, NEAR imaged Eros every 15 degrees of rotation over a period of about 5.8 hrs. At this time the distance between the asteroid and spacecraft was approximately 4638 miles (7730 km). These images taken during approach to the asteroid are used by mission navigators and operators to make the proper corrections in the spacecraft's trajectory during the critical burns coming up on Feb. 8 and Feb. 14. As an added bonus, these "OpNav" (optical navigation) images provide an increasingly detailed view of surface features on the asteroid. The resolution has increased to about 0.5 miles (0.8 km) per pixel, revealing the presence of 3 small craters on the surface. Over the next 10 days our view of the surface will become increasingly detailed and will allow for nearly global low resolution mapping of the asteroid before NEAR goes into orbit about Eros on Valentine's Day, Feb. 14. Once in orbit, NEAR's suite of scientific instruments will allow for global mapping of the asteroid at very high resolution. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Eros details enhanced by com
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PIA02466
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros details enhanced by computer processing |
| Original Caption Released with Image |
The NEAR camera's ability to show details of Eros's surface is limited by the spacecraft's distance from the asteroid. That is, the closer the spacecraft is to the surface, the more that details are visible. However mission scientists regularly use computer processing to squeeze an extra measure of information from returned data. In a technique known as "superresolution", many images of the same scene acquired at very, very slightly different camera pointing are carefully overlain and processed to bright out details even smaller than would normally be visible. In this rendition constructed out of 20 image frames acquired Feb. 12, 2000, the images have first been enhanced ("high-pass filtered") to accentuate small-scale details. Superresolution was then used to bring out features below the normal ability of the camera to resolve. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Eros in stereo
PIA02471
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros in stereo |
| Original Caption Released with Image |
Stereo imaging will be an important tool on NEAR for geologic analysis of Eros, because it provides three-dimensional information on the asteroid's landforms and structures. This anaglyph can be viewed using red-blue glasses to show Eros in stereo. It was constructed from images taken on February 14 and 15 that showed the same part of Eros from two slightly different viewing perspectives. The smallest feature visible is 100 feet (30 meters) across. For this image the spacecraft position was not optimum for stereo, but it will improve over the next few days allowing better 3-D views. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Two Views of Mathilde
PIA02479
Sol (our sun)
Multi-Spectral Imager
| Title |
Two Views of Mathilde |
| Original Caption Released with Image |
Two different views of asteroid 253 Mathilde were obtained by the NEAR spacecraft on June 27, 1997. The image at left was obtained as the spacecraft approached Mathilde with its camera pointed near the direction of the Sun, only a few of the prominent ridges on Mathilde are illuminated. The visible area at left is 29 km (18 miles) high, and the phase angle (the angle from Sun-Mathilde spacecraft) is 136°. As the spacecraft receded from Mathilde, it observed the asteroid (about 60 km or 38 miles across) almost fully lit by the Sun at a phase angle of 43° (right image). Mathilde's irregular shape results from a long history of severe collisions with smaller asteroids. The largest visible crater is 30 km (19 miles) in diameter. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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NEAR: From Planning to Data
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PIA02489
Sol (our sun)
Near Infra-Red Spectrometer
| Title |
NEAR: From Planning to Data Analysis |
| Original Caption Released with Image |
Planning and acquiring observations from NEAR's Near-Infrared Spectrometer (NIS) is a complex process that requires a detailed understanding of the strange shape and the rotational state of Eros. On February 13-14, 2000, just before insertion into Eros orbit, NEAR passed between Eros and the Sun. This geometry is called a low phase angle. It is optimum for spectroscopic observations, so at that time NIS obtained some of its most valuable data. To plan these activities in the preceding months, the NEAR science team developed a series of global NIS observation sequences like the one depicted in the left image. Here, NIS was instructed to scan its mirror back and forth across Eros while the spacecraft did a slow slew from top to bottom. The image shows the predicted coverage as viewed from directly over the north pole of a computerized "shape model" of Eros. Many such observation sequences were performed flawlessly on the spacecraft during the "low phase-angle flyby," and the highest-quality spectra were combined to show the resulting NIS coverage of Eros in the map on the right. The green and red regions show areas at high northern latitudes with the best coverage by NIS. Analysis of the NIS spectra is providing clues about the mineralogy and composition of Eros, and perhaps its early history and evolution. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Impact at High Noon
PIA02499
Sol (our sun)
Multi-Spectral Imager
| Title |
Impact at High Noon |
| Original Caption Released with Image |
For people who live in mountain valleys, daylight can be a short-lived experience. Mountains to the east make the Sun rise later in the morning, while mountains to the west make the Sun set earlier in the evening. The brevity of daytime in a valley is accentuated during the shortened days of winter. The floor of the 5.5-kilometer (3.4-mile) diameter impact crater that dominates one face of Eros experiences the ultimate in short daylight hours. Three factors conspire to make this true. Firstly, Eros rotates rapidly, once every 5.27 hours. Secondly, the crater's 0.9-kilometer (0.56-mile) high walls tend to block direct sunlight from the floor, even while the outside of the crater is illuminated. Thirdly, during the current season on Eros, the Sun never makes it high in the sky in this location. This NEAR Shoemaker image, taken April 1, 2000, from a range of 209 kilometers (130 miles), caught the crater near local noon with the Sun highest in the sky. On that day, a hardy astronaut standing at the bottom of the crater would have experienced 1 hour and 45 minutes of daylight. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Interesting Structural Featu
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PIA02482
Sol (our sun)
Multi-Spectral Imager
| Title |
Interesting Structural Features on Eros |
| Original Caption Released with Image |
This image of the interior of Eros' saddle area, taken at a range of 204 km (127 miles), displays a paucity of craters compared to the surface on the right hand side of the image. The saddle displays many interesting structural features. Visible on the left wall are a series of closely spaced grooves that follow the terrain downslope. Opposite, on the upper right wall, trending towards the back of the saddle is a prominent ridge. Boulders are visible throughout this image. Features as small as 20 meters (65 feet) are discernable in this image. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Large Crater on Eros
PIA02481
Sol (our sun)
Multi-Spectral Imager
| Title |
Large Crater on Eros |
| Original Caption Released with Image |
This image mosaic of the large crater at Eros' center was taken on March 3, 2000 during an optical navigation imaging sequence from a range of 127 miles (204 kilometers). This same area was imaged following orbit insertion at a range of approximately 210 miles (330 kilometers) on February 14th. This picture resolves features as small as 65 feet (20 meters) across compared to the resolution of 100 feet (30 meters) in the earlier image. The shadow cast by the boulder near the floor of the crater is now visible. The walls of the crater display some distinctive variations in their albedo or reflectivity. The upper part of the walls tend to be bright, while the lower portions of the walls and the crater floor show patches of darker or less reflective materials. These albedo patterns are also visible on other crater walls. To the right of the large crater, two sets of closely spaced orthogonal grooves are visible. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Eros Surface Morphology
PIA02491
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros Surface Morphology |
| Original Caption Released with Image |
On March 10, 2000, this image of Eros was acquired by the imager on the NEAR Shoemaker spacecraft, from a range of 206 kilometers (127 miles). The area shown in the image is 10 kilometers (6.2 miles) across, and the smallest detail visible is 20 meters (65 feet) across. Here, the spacecraft was over the shaded interior of the "saddle," looking over the north polar region to the limb. The shadowing at the upper right is due to oblique lighting. The narrowness of the illuminated part of Eros in the center of the frame results from viewing the narrow "waist" of Eros' irregular peanut-like shape. This image is from one of a large number of imaging sequences acquired during the first of two "200-kilometer" (124-mile) orbits. The second 200-kilometer orbit, in autumn 2000, will provide similar views of southern latitudes. The purpose of many of the sequences in this orbit is to view the northern and equatorial latitudes of the asteroid under conditions similar to those at the time of this image, looking straight down on a part of the surface (called a "low emission angle") while the surface is obliquely illuminated (called a "high incidence angle"). The resulting views bring out surface morphology and are crucial to making a global map of Eros. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Oblique View of Eros' Crater
PIA02484
Sol (our sun)
Multi-Spectral Imager
| Title |
Oblique View of Eros' Crater |
| Original Caption Released with Image |
This image, showing an oblique view of Eros' large central crater, was taken at a resolution of about 20 meters (65 feet) per pixel. The brightness or albedo patterns on the walls of this crater are clearly visible, with the brighter materials near the tops of the walls and darker materials on the lower walls. Boulders are seen inside this crater and the smaller nearby craters. The higher density of craters to the left of the large crater implies that this region is older than the smoother area seen associated with the saddle region on the opposite side of the asteroid. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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A Trio of Craters on Eros
PIA02488
Sol (our sun)
Multi-Spectral Imager
| Title |
A Trio of Craters on Eros |
| Original Caption Released with Image |
The Near Earth Asteroid Rendezvous (NEAR) spacecraft snapped the image on the left (Image of the Day Feb. 13, 2000 B) during its approach to Eros on Feb. 11, 2000, from a range of 2590 kilometers (1,609 miles). This image shows a heart-shaped depression about 5 km (3 miles) long. The image mosaic on the right was taken from 204 km (127 miles) on March 3, 2000 and reveals that the mysterious heart-shaped feature is actually 3 separate craters. The oblique lighting conditions and low resolution of the earlier image created the illusion of a heart shape. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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Eros'North Pole
PIA02498
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros'North Pole |
| Original Caption Released with Image |
For much of the past five weeks, imaging activities on the NEAR Shoemaker spacecraft have focused on the high northern latitudes of Eros. The point at which the Sun is directly overhead - known as the "subsolar point" - has been steadily moving from Eros' northern regions toward the equator as the asteroid's seasons progress. As this happens, the northern hemisphere is illuminated less and less, and previously dark southern latitudes progressively come into view. In this image, taken March 19, 2000, from a range of 205 kilometers (127 miles), the asteroid's north pole is in the upper right of the frame. The whole scene is 7.4 kilometers (4.6 miles) across. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
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