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Charon Discovery Image
| title |
Charon Discovery Image |
| date |
06.22.1978 |
| description |
On 22 June 1978, an astronomer at the U.S. Naval Observatory in Washington, D.C. was making routine measurements of photographic plates taken with the 1.55-meter (61-inch) Kaj Strand Astrometric Reflector at the USNO Flagstaff Station in Arizona. The purpose of these images was to refine the orbit of the far-flung planet Pluto to help compute a better ephemeris for this distant object. Astronomer James W. Christy had noticed that a number of the images of Pluto appeared elongated, but images of background stars on the same plate did not. Other plates showed the planet as a tiny, round dot. Christy examined a number of Pluto images from the USNO archives, and he noticed the elongations again. Furthermore, the elongations appeared to change position with respect to the stars over time. After eliminating the possibility that the elongations were produced by plate defects and background stars, the only plausible explanation was that they were caused by a previously unknown moon orbiting Pluto at a distance of about 19,600 kilometers (12,100 miles) with a period of just over six days. On 7 July 1978, the discovery was formally announced to the astronomical community and the world by the IAU Central Bureau for Astronomical Telegrams via IAU Circular 3241. The discovery received the provisional designation "1978 P 1", Christy proposed the name "Charon", after the mythological ferryman who carried souls across the river Acheron, one of the five mythical rivers that surrounded Pluto's underworld. Over the course of the next several years, another USNO astronomer, the late Robert S. Harrington, calculated that Pluto and its newly-found moon would undergo a series of mutual eclipses and occultations, beginning in early 1985. On 17 February 1985 the first successful observation of one of these transits was made at with the 0.9-meter (36-inch) reflector at the University of Texas McDonald Observatory, within 40 minutes of Harrington's predicted time. The IAU Circular announcing these confirming observations was issued on 22 February 1985. With this confirmation, the new moon was officially named Charon. Pluto was discovered at Lowell Observatory in 1930 by the late Clyde W. Tombaugh, an amateur astronomer from Kansas who was hired by the Observatory specifically to photograph the sky with a special camera and search for the planet predicted by the Observatory's founder, Percival Lowell. Lowell had deduced the existence of a "Planet X" by studying small anomalies in the orbits of Uranus and Neptune. As it turned out, Pluto's discovery was almost entirely serendipitous, Pluto's tiny mass was far too small to account for the anomalies, which were resolved when Voyager 2 determined more precise masses for Uranus and Neptune. The discovery of Charon has led to a much better understanding of just how tiny Pluto is. Its diameter is about 2274 km (1413 miles), and its mass is 0.25% of the mass of the Earth. Charon has a diameter of about 1172 kilometers (728, miles) and a mass of about 22% that of Pluto. The two worlds circle their common center of mass with a period of 6.387 days and are locked in a "super-synchronous" rotation: observers on Pluto's surface would always see Charon in the same part of the sky relative to their local horizon. Normally Pluto is considered the most distant world in the solar system, but during the period from January 1979 until February 1999 it was actually closer to the Sun than Neptune. It has the most eccentric and inclinced orbit of any of the major planets. This orbit won't bring Pluto back to its discovery position until the year 2178! *Image Credit*: U.S. Naval Observatory |
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Hubble Captures Detailed Ima
…
| title |
Hubble Captures Detailed Image of Uranus' Atmosphere |
| date |
07.03.1995 |
| description |
Hubble Space Telescope has peered deep into Uranus' atmosphere to see clear and hazy layers created by a mixture of gases. Using infrared filters, Hubble captured detailed features of three layers of Uranus' atmosphere. Hubble's images are different from the ones taken by the Voyager 2 spacecraft, which flew by Uranus 10 years ago. Those images - not taken in infrared light - showed a greenish-blue disk with very little detail. The infrared image allows astronomers to probe the structure of Uranus' atmosphere, which consists of mostly hydrogen with traces of methane. The red around the planet's edge represents a very thin haze at a high altitude. The haze is so thin that it can only be seen by looking at the edges of the disk, and is similar to looking at the edge of a soap bubble. The yellow near the bottom of Uranus is another hazy layer. The deepest layer, the blue near the top of Uranus, shows a clearer atmosphere. Image processing has been used to brighten the rings around Uranus so that astronomers can study their structure. In reality, the rings are as dark as black lava or charcoal. This false color picture was assembled from several exposures taken July 3, 1995 by the Wide Field Planetary Camera-2. The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science. This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu *Image Credit*: Erich Karkoschka (University of Arizona Lunar & Planetary Lab) and NASA |
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Hubble Spots Northern Hemisp
…
| title |
Hubble Spots Northern Hemispheric Clouds on Uranus |
| date |
07.31.1997 |
| description |
Using visible light, astronomers for the first time this century have detected clouds in the northern hemisphere of Uranus. The newest images, taken July 31 and Aug. 1, 1997 with NASA Hubble Space Telescope's Wide Field and Planetary Camera 2, show banded structure and multiple clouds. Using these images, Dr. Heidi Hammel (Massachusetts Institute of Technology) and colleagues Wes Lockwood (Lowell Observatory) and Kathy Rages (NASA Ames Research Center) plan to measure the wind speeds in the northern hemisphere for the first time. Uranus is sometimes called the "sideways" planet, because its rotation axis tipped more than 90 degrees from the planet's orbit around the Sun. The "year" on Uranus lasts 84 Earth years, which creates extremely long seasons - winter in the northern hemisphere has lasted for nearly 20 years. Uranus has also been called bland and boring, because no clouds have been detectable in ground-based images of the planet. Even to the cameras of the Voyager spacecraft in 1986, Uranus presented a nearly uniform blank disk, and discrete clouds were detectable only in the southern hemisphere. Voyager flew over the planet's cloud tops near the dead of northern winter (when the northern hemisphere was completely shrouded in darkness). Spring has finally come to the northern hemisphere of Uranus. The newest images, both the visible-wavelength ones described here and those taken a few days earlier with the Near Infrared and Multi-Object Spectrometer (NICMOS) by Erich Karkoschka (University of Arizona), show a planet with banded structure and detectable clouds. Two images are shown here. The "aqua" image (on the left) is taken at 5,470 Angstroms, which is near the human eye's peak response to wavelength. Color has been added to the image to show what a person on a spacecraft near Uranus might see. Little structure is evident at this wavelength, though with image-processing techniques, a small cloud can be seen near the planet's northern limb (rightmost edge). The "red" image (on the right) is taken at 6,190 Angstroms, and is sensitive to absorption by methane molecules in the planet's atmosphere. The banded structure of Uranus is evident, and the small cloud near the northern limb is now visible. Scientists are expecting that the discrete clouds and banded structure may become even more pronounced as Uranus continues in its slow pace around the Sun. "Some parts of Uranus haven't seen the Sun in decades," says Dr. Hammel, "and historical records suggest that we may see the development of more banded structure and patchy clouds as the planet's year progresses." Some scientists have speculated that the winds of Uranus are not symmetric around the planet's equator, but no clouds were visible to test those theories. The new data will provide the opportunity to measure the northern winds. Hammel and colleagues expect to have results soon. The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by, the Goddard Spaced Flight Center for NASA's Office of Space Science. This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu *Image Credit*: Heidi Hammel (Massachusetts Institute of Technology), NASA |
|
Hubble Captures Detailed Ima
…
| Title |
Hubble Captures Detailed Image of Uranus's Atmosphere |
|
Hubble Watches Uranus
| Title |
Hubble Watches Uranus |
|
Hubble Views of Dust Disks a
…
| Title |
Hubble Views of Dust Disks and Rings Surrounding Young Stars Yield Clues |
| General Information |
What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. NASA's Hubble Space Telescope has given astronomers their first views of a dust ring around the star HR 4796A and a dark gap dividing an immense dust disk around the star HD 141569. These images may provide important clues to possible planet formation. Read more: * Release Text [ http://hubblesite.org/newscenter/archive/releases/1999/03/text/ ] |
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Hubble Watches Uranus
| Title |
Hubble Watches Uranus |
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Hubble Finds Many Bright Clo
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| Title |
Hubble Finds Many Bright Clouds on Uranus |
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Centaur's Bright Surface Spo
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| Title |
Centaur's Bright Surface Spot Could be Crater of Fresh Ice |
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Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
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Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
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Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
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Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
|
Hands-On Book of Hubble Imag
…
| Title |
Hands-On Book of Hubble Images Allows the Visually Impaired to "Touch the Universe |
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The Colorful Lives of the Ou
…
| Title |
The Colorful Lives of the Outer Planets |
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The Colorful Lives of the Ou
…
| Title |
The Colorful Lives of the Outer Planets |
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The Colorful Lives of the Ou
…
| Title |
The Colorful Lives of the Outer Planets |
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The Colorful Lives of the Ou
…
| Title |
The Colorful Lives of the Outer Planets |
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The Colorful Lives of the Ou
…
| Title |
The Colorful Lives of the Outer Planets |
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The Colorful Lives of the Ou
…
| Title |
The Colorful Lives of the Outer Planets |
|
Hubble Spots Northern Hemisp
…
| Title |
Hubble Spots Northern Hemispheric Clouds on Uranus |
| Description |
Goddard Spaced Flight Center for NASA's Office of Space Science. This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http:// oposite.stsci.edu/pubinfo/, Using visible light, astronomers for the first time this century have detected clouds in the northern hemisphere of Uranus. The newest images, taken July 31 and Aug. 1, 1997 with NASA Hubble Space Telescope's Wide Field and Planetary Camera 2, show banded structure and multiple clouds. Using these images, Dr. Heidi Hammel (Massachusetts Institute of Technology) and colleagues Wes Lockwood (Lowell Observatory) and Kathy Rages (NASA Ames Research Center) plan to measure the wind speeds in the northern hemisphere for the first time. Uranus is sometimes called the "sideways" planet, because its rotation axis tipped more than 90 degrees from the planet's orbit around the Sun. The "year" on Uranus lasts 84 Earth years, which creates extremely long seasons - winter in the northern hemisphere has lasted for nearly 20 years. Uranus has also been called bland and boring, because no clouds have been detectable in ground-based images of the planet. Even to the cameras of the Voyager spacecraft in 1986, Uranus presented a nearly uniform blank disk, and discrete clouds were detectable only in the southern hemisphere. Voyager flew over the planet's cloud tops near the dead of northern winter (when the northern hemisphere was completely shrouded in darkness). Spring has finally come to the northern hemisphere of Uranus. The newest images, both the visible-wavelength ones described here and those taken a few days earlier with the Near Infrared and Multi-Object Spectrometer (NICMOS) by Erich Karkoschka (University of Arizona), show a planet with banded structure and detectable clouds. Two images are shown here. The "aqua" image (on the left) is taken at 5,470 Angstroms, which is near the human eye's peak response to wavelength. Color has been added to the image to show what a person on a spacecraft near Uranus might see. Little structure is evident at this wavelength, though with image-processing techniques, a small cloud can be seen near the planet's northern limb (rightmost edge). The "red" image (on the right) is taken at 6,190 Angstroms, and is sensitive to absorption by methane molecules in the planet's atmosphere. The banded structure of Uranus is evident, and the small cloud near the northern limb is now visible. Scientists are expecting that the discrete clouds and banded structure may become even more pronounced as Uranus continues in its slow pace around the Sun. "Some parts of Uranus haven't seen the Sun in decades," says Dr. Hammel, "and historical records suggest that we may see the development of more banded structure and patchy clouds as the planet's year progresses." Some scientists have speculated that the winds of Uranus are not symmetric around the planet's equator, but no clouds were visible to test those theories. The new data will provide the opportunity to measure the northern winds. Hammel and colleagues expect to have results soon. The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the |
| Date |
11.20.1997 |
|
Three planetary views from t
…
johnsonspacecentermediaarchi
…
Three new plantetary views f
…
S98-20016
| mediatype |
IMAGE |
| mediatype |
image |
| date |
1998-12-07 |
| creator |
NASA |
| identifier |
S98-20016 |
|
The New Solar System
PIA02973
| Title |
The New Solar System |
| Original Caption Released with Image |
This solar-system montage of the nine planets and 4 large moons of Jupiter in our solar system are set against a false-color view of the Rosette Nebula. The light emitted from the Rosette Nebula results from the presence of hydrogen (red), oxygen (green) and sulfur (blue). Most of the planetary images in this montage were obtained by NASA's planetary missions, which have dramatically changed our understanding of the solar system in the past 30 years. The following lists the mission and link for additional information on each object and image.Mercury/Mariner 10 [ http://photojournal.jpl.nasa.gov/catalog/PIA02418 ]Venus/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA00072 ]Earth/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA00728 ]Moon/Lunar Orbiter [ http://photojournal.jpl.nasa.gov/catalog/PIA00094 ]Mars/Viking Orbiter 1 & 2 [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/wall/mars/hemisph.html ]Jupiter/Voyager 1 [ http://photojournal.jpl.nasa.gov/catalog/PIA01509 ]Io/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA02309 ]Europa/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA00502 ]Ganymede/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA01666 ]Callisto/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA01298 ]Saturn/Voyager 1 [ http://photojournal.jpl.nasa.gov/catalog/PIA01383 ]Uranus/Voyager 2 [ http://photojournal.jpl.nasa.gov/catalog/PIA00032 ]Neptune/Voyager 2 [ http://photojournal.jpl.nasa.gov/catalog/PIA02210 ]Pluto/Hubble Space Telescope [ http://photojournal.jpl.nasa.gov/catalog/PIA00827 ]Rosette Nebula/Kitt Peak [ http://www.noao.edu/image_gallery/html/im0557.html ] |
|
Hubble Spots Northern Hemisp
…
PIA01279
Sol (our sun)
Wide Field Planetary Camera
…
| Title |
Hubble Spots Northern Hemispheric Clouds on Uranus |
| Original Caption Released with Image |
Goddard Spaced Flight Center for NASA's Office of Space Science. This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http:// oposite.stsci.edu/pubinfo/, Using visible light, astronomers for the first time this century have detected clouds in the northern hemisphere of Uranus. The newest images, taken July 31 and Aug. 1, 1997 with NASA Hubble Space Telescope's Wide Field and Planetary Camera 2, show banded structure and multiple clouds. Using these images, Dr. Heidi Hammel (Massachusetts Institute of Technology) and colleagues Wes Lockwood (Lowell Observatory) and Kathy Rages (NASA Ames Research Center) plan to measure the wind speeds in the northern hemisphere for the first time. Uranus is sometimes called the "sideways" planet, because its rotation axis tipped more than 90 degrees from the planet's orbit around the Sun. The "year" on Uranus lasts 84 Earth years, which creates extremely long seasons - winter in the northern hemisphere has lasted for nearly 20 years. Uranus has also been called bland and boring, because no clouds have been detectable in ground-based images of the planet. Even to the cameras of the Voyager spacecraft in 1986, Uranus presented a nearly uniform blank disk, and discrete clouds were detectable only in the southern hemisphere. Voyager flew over the planet's cloud tops near the dead of northern winter (when the northern hemisphere was completely shrouded in darkness). Spring has finally come to the northern hemisphere of Uranus. The newest images, both the visible-wavelength ones described here and those taken a few days earlier with the Near Infrared and Multi-Object Spectrometer (NICMOS) by Erich Karkoschka (University of Arizona), show a planet with banded structure and detectable clouds. Two images are shown here. The "aqua" image (on the left) is taken at 5,470 Angstroms, which is near the human eye's peak response to wavelength. Color has been added to the image to show what a person on a spacecraft near Uranus might see. Little structure is evident at this wavelength, though with image-processing techniques, a small cloud can be seen near the planet's northern limb (rightmost edge). The "red" image (on the right) is taken at 6,190 Angstroms, and is sensitive to absorption by methane molecules in the planet's atmosphere. The banded structure of Uranus is evident, and the small cloud near the northern limb is now visible. Scientists are expecting that the discrete clouds and banded structure may become even more pronounced as Uranus continues in its slow pace around the Sun. "Some parts of Uranus haven't seen the Sun in decades," says Dr. Hammel, "and historical records suggest that we may see the development of more banded structure and patchy clouds as the planet's year progresses." Some scientists have speculated that the winds of Uranus are not symmetric around the planet's equator, but no clouds were visible to test those theories. The new data will provide the opportunity to measure the northern winds. Hammel and colleagues expect to have results soon. The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the |
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