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Eros' Bland Butterscotch Col
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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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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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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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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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Sunset on Eros
PIA02493
Sol (our sun)
Multi-Spectral Imager
| Title |
Sunset on Eros |
| Original Caption Released with Image |
Eros' irregular shape gives rise to some stunning vistas at the time of sunrise or sunset. On March 6, 2000, the imager on the NEAR Shoemaker spacecraft caught this view of a stunning sunset. In the pitch black foreground the Sun has already set, but just over the horizon another part of the asteroid remains lit. Eros' rotation period is just 5 hours, 16 minutes, so in the course one 24-hour Earth day an observer on Eros would be treated to four full cycles of sunrises and sunsets. 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 Color at Higher Resolut
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PIA02492
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros Color at Higher Resolution |
| Original Caption Released with Image |
As the NEAR Shoemaker spacecraft descends into lower orbits around Eros, it continually returns higher spatial resolution images of the asteroid. The true color image at left was taken February 12, 2000, from a range of 1,748 kilometers (1,083 miles), and shows details only as small as 180 meters (590 feet) across. It was taken two days before orbit insertion, as part of an image sequence designed to provide moderate-resolution color mapping of Eros at a near-constant viewing geometry. The true color image inset at right was taken February 29 from a range of 283 kilometers (175 miles) and shows much smaller details only 27 meters (89 feet) across. The higher spatial resolution (by a factor of six) brings out a whole class of surface details that were either invisible or at the margin of visibility in the earlier images. For example, the bright material on the wall of the large crater in the inset image is barely evident in the lower-resolution image at left, but by virtue of its limited spatial coverage the inset image lacks information on the crater's regional geologic setting. NEAR Shoemaker's imaging strategy makes use of both types of images, with lower-resolution images providing "context" for higher-resolution images that bring specific features into sharper focus. 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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Glimpses into Eros' Shadows
PIA02487
Sol (our sun)
Multi-Spectral Imager
| Title |
Glimpses into Eros' Shadows |
| Original Caption Released with Image |
This image mosaic, showing Eros' saddle and a shadowed feature to its left, was taken on March 3, 2000 from a distance of 204 kilometers (127 miles). In this picture features as small as 20 meters (65 feet) across are visible. This is the best view to date of this area. The sun is coming from the northeast illuminating a shadowed feature that consists of three large craters situated adjacent to each other. The two largest are each about 4-5 km (2-3 miles) across. Because the sun is very low with respect to these craters, even small topographic features cast long shadows, making them easier to see. As a result, several boulders on the crater walls can be distinguished, ranging from about 50 to 100 meters in diameter. The saddle (on the right of the mosaic) is relatively smooth with few impact craters, and has several grooves running across it. At the top of the saddle are several curved grooves that are brighter than the surrounding surface. Unusual brightness patterns are also visible in the crater at the top left of the mosaic. The walls of the crater appear to be more reflective and its floor less reflective than nearby parts 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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Eros' North Polar Region
PIA02490
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros' North Polar Region |
| Original Caption Released with Image |
On March 11, 2000, this image of Eros' north polar region 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. Most of the north polar region is heavily cratered but the region to the left (part of the "saddle") has a lower crater density, indicating that the surface has been modified since it first formed. Eros' rotational axis lies nearly parallel to its orbital plane, much as with the planet Uranus, giving the asteroid exaggerated "seasons." Now, it is northern summer and the north pole is in continuous sunlight. The Sun will set there this June, at Eros' equivalent of Earth's autumnal equinox. At that time, Eros' south pole will begin 12 months of continuous illumination while the north pole remains in darkness. 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' Aging Craters
PIA02497
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros' Aging Craters |
| Original Caption Released with Image |
Eros' many craters have a range of ages dating back to the last time the asteroid's surface was "wiped clean" by geologic processes. This NEAR Shoemaker image of the tip of the asteroid, taken March 6, 2000, from a range of 201 kilometers (125 miles), shows craters with a variety of shapes and sizes. When small craters first form, they typically have sharp rims and round floors. As they age, progressively smaller craters are superimposed, rounding the rims and pitting the walls and floors until the original underlying crater becomes almost unrecognizable. 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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Cratered Terrain on Eros
PIA02483
Sol (our sun)
Multi-Spectral Imager
| Title |
Cratered Terrain on Eros |
| Original Caption Released with Image |
This mosaic of 2 images, showing a cratered region of Eros located at the end of the elongated asteroid, was taken at a resolution of about 21 meters (69 feet) per pixel. A few of the craters show brightness (albedo) patterns on their walls, where the top portions of the walls are brighter than the surrounding terrain. The floors and lower portions of the walls of these craters have patches that appear darker than the surrounding terrain. A few boulders are also visible in this region. Some shallow, subdued troughs can also be seen trending vertically down the lower part 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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Rim of Saddle Region on Eros
PIA02485
Sol (our sun)
Multi-Spectral Imager
| Title |
Rim of Saddle Region on Eros |
| Original Caption Released with Image |
This image of the northeast rim of the saddle region on Eros was taken after NEAR entered into its 200 kilometer orbit on March 3, 2000. The resolution of this image is 20 meters (65 feet) per pixel. On the right are bright sinuous features associated with a ridge seen in previous images of the day. Parallel, closely spaced grooves are seen in the floor of the saddle. A cluster of boulders, ubiquitous on Eros, is seen in a small crater on the 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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The Sculptured Surface of Er
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PIA02480
Sol (our sun)
Multi-Spectral Imager
| Title |
The Sculptured Surface of Eros |
| Original Caption Released with Image |
NEAR takes several images mosaics of Eros daily for purposes of navigating the spacecraft. The one shown here was taken February 29, 2000, from a range of 289 kilometers (180 miles). It shows features as small as 30 meters (100 feet) across. All of the mosaics show the same territory over and over, but changes in lighting plus the gradual decrease in the spacecraft's range to the surface are both constantly bringing out new details. The very oblique illumination in this mosaic is ideal for bringing out small landforms. Many parts of the asteroid have "grooves," linear troughs about 100 meters (330 feet) wide and several kilometers long. Similar features have also been observed on other asteroids such as Gaspra, and they are especially numerous on Mars' moon Phobos. Their origin isn't completely understood, but formation of the grooves probably involves fracturing of the asteroid's subsurface in some way. 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 Up Close
PIA02901
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros Up Close |
| Original Caption Released with Image |
Since April 11, the NEAR Shoemaker spacecraft has orbited Eros at an altitude of 100 kilometers (62 miles) from the asteroid's center. Images acquired from this orbit will be used to make a high-resolution map of the illuminated portion of the asteroid. Each spot on the surface will be imaged under a variety of lighting and viewing conditions to bring out different features. In this image, taken April 17, 2000, from a height of 101 kilometers (63 miles), the shadows highlight small-scale surface features. The surface is pockmarked with craters ranging in size up to the 2.8-kilometer (1.74-mile) diameter crater in the center of the image. The smallest craters which can be resolved are about 20 meters (65 feet) across. In lower right corner of the image, 20-meter boulders can be seen that were not evident in images from higher altitudes. 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 Eros' Northern Hem
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PIA02924
Sol (our sun)
Multi-Spectral Imager
| Title |
Mosaic of Eros' Northern Hemisphere |
| Original Caption Released with Image |
NEAR Shoemaker obtains the best views of subtle details in Eros' landforms when the spacecraft's imager looks straight down at the surface, and the Sun illuminates the surface at a very low angle. Such lighting brings out even tiny undulations in the surface and makes features stand out sharply. This image -- acquired June 6, 2000, from an orbital altitude of 49 kilometers (30 miles) -- was taken under those ideal conditions. The landscape is textured by low ridges and grooves running from left to right, with numerous boulders sprinkled on them. The whole scene is 1.4 kilometers (0.9 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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Common Craters (Earth and Er
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PIA02953
Sol (our sun)
Multi-Spectral Imager
| Title |
Common Craters (Earth and Eros) |
| Original Caption Released with Image |
The late Dr. Eugene Shoemaker, who many consider the founder of modern planetary science, did pioneering work at Meteor Crater, Arizona, documenting the effects of impact cratering as a planetary process. When part of a comet or asteroid strikes a planet or another asteroid, the resulting shock wave and excavation of rock and soil leave a characteristic landform that looks much the same from planet to planet, asteroid to asteroid. To illustrate the point, this NEAR Shoemaker image of a crater on Eros (left), taken July 6, 2000, from an orbital altitude of 50 kilometers (31 miles), is displayed next to and at approximately the same scale as Meteor 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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A Swath of Eros
PIA02926
Sol (our sun)
Multi-Spectral Imager
| Title |
A Swath of Eros |
| Original Caption Released with Image |
NEAR Shoemaker's scientific observations of Eros focus on different priorities as the spacecraft descends into lower orbits. For example, during the 100-kilometer (62-mile)orbit from April 11 - 22, 2000, the camera's mission was to build a global photomosaic under optimal viewing conditions. Due to the asteroid's irregular shape, doing this required imaging Eros repeatedly until each spot had been covered just right. This swath of images - taken April 13 as part of that mapping campaign - shows several of the asteroid's major features. From top to bottom, these include large craters in the north polar region, part of the ridge that wraps one-third of the way around Eros, the western part of the saddle, and a dense field of enormous boulders. 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' Littered Surface from
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PIA02956
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros' Littered Surface from Low Altitude |
| Original Caption Released with Image |
NEAR Shoemaker's incredibly detailed images from the low orbit around Eros continue to surpass the expectations of the mission team. This picture, taken July 24, 2000, from an orbital altitude of 36 kilometers (22 miles), shows a region about 900 meters (3,000 feet) across. Some of the largest boulders in the scene, such as the broken one at the upper left, show angular shapes. Many smaller boulders litter the scene, the smallest ones visible here are about 6 meters (19 feet) across. Regolith seems to have banked up against several rocks. In some places, like the large crater below the center of the picture, regolith also appears to have filled, or "ponded," in low spots. 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: Closest View Yet! (36
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PIA02951
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros: Closest View Yet! (36 km altitude) |
| Original Caption Released with Image |
In NEAR Shoemaker's long-awaited close-up images of Eros, the asteroid's small-scale features are revealing their fascinating diversity. This picture, taken July 8, 2000, from an orbital altitude of 36 kilometers (22 miles), shows a variety of differently shaped boulders. Some are nearly round, whereas others are elongated or even blade-shaped. Such varied shapes might arise from differences in the strength and fracturing of preexisting rock. The whole scene is 1.4 kilometers (0.8 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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Eros' Latitude and Longitude
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PIA02922
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros' Latitude and Longitude Grid |
| Original Caption Released with Image |
The most familiar reference system for locating places on the surface of a planetary body is latitude and longitude. On a spherical body like Earth, these measures have a comfortable, predictable feel to them - despite the difficulty in showing a spherical planet on a flat map. However, the irregular peanut-like shape of Eros lends the asteroid's latitude-longitude grid a surprising character. This image of the north polar region was taken from NEAR Shoemaker March 31, 2000, from an orbital altitude of 207 kilometers (129 miles). The image has been overlain with lines of latitude and longitude. Latitude is measured in degrees from the equator to the pole, longitude is measured in degrees west of a "prime meridian." In both cases, the vertex of the angle being measured is the center of Eros. The wandering, curved shapes of the lines are caused by the highly nonspherical and irregular asteroid 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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Mosaic of Eros' Northern Hem
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PIA02923
Sol (our sun)
Multi-Spectral Imager
| Title |
Mosaic of Eros' Northern Hemisphere |
| Original Caption Released with Image |
While NEAR Shoemaker orbits Eros, the asteroid appears too large for the camera's field of view. In order to get a complete view of the surface from a particular vantage point, several images are mosaiced. To do this, the digital images returned by the spacecraft are draped over a computer model of the asteroid's shape. This spectacular view -- looking down on the north polar region -- was constructed from six images taken February 29, 2000, from an orbital altitude of about 200 kilometers (124 miles). This vantage point highlights the major physiographic features of the northern hemisphere: the saddle seen at the bottom, the 5.3-kilometer (3.3-mile) diameter crater at the top, and a major ridge system running between the two features that spans at least one-third of the asteroid's circumference. 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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The Shape of Eros
PIA02955
Sol (our sun)
Multi-Spectral Imager
| Title |
The Shape of Eros |
| Original Caption Released with Image |
Looking at a few pictures of Eros under the right lighting conditions gives a reasonable idea of the shape of the asteroid, but analysis of NEAR Shoemaker data requires a very accurate digital model of Eros' shape. This "shape model" helps the NEAR team analyze images and other types of data. For example, comparing the brightness of imaged regions with the orientation of the corresponding parts of the surface, taken from the shape model, allows scientists to determine whether bright areas are due to just surface orientation or also to surface properties. By "filling |
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Inside Eros' Large Crater
PIA02925
Sol (our sun)
Multi-Spectral Imager
| Title |
Inside Eros' Large Crater |
| Original Caption Released with Image |
NEAR Shoemaker continues to take pictures of Eros under different lighting conditions and at better spatial resolution. This approach maximizes the amount of recognizable detail in the surface, while placing that detail into the context of the asteroidÃs large-scale geography. This image approximates the view from the edge of the large, 5.3-kilometer (3.3-mile) diameter crater, looking into its depths. It was acquired on June 6, 2000, from an orbital altitude of 49 kilometers (30 miles). The whole scene is 1.4 kilometers (0.9 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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A Changing Picture of Eros
PIA03116
Sol (our sun)
Multi-Spectral Imager
| Title |
A Changing Picture of Eros |
| Original Caption Released with Image |
As NEAR Shoemaker has descended to lower orbits around Eros and returned higher spatial resolution pictures, knowledge of surface landforms has grown dramatically. The effect of changing spatial resolution can be illustrated by comparing these pictures of the large, 5.3-kilometer(3.3-mile) diameter crater taken at different distances above the surface. All of the views are shown with north to the top. The upper left picture, taken February 12, 2000, from 1,682 kilometers(1,045 miles) above the crater, shows the feature's outline with several smaller craters superimposed on its southern section. There are only hints of bright materials on the north wall of the crater. The upper right view, taken April 2 from 193 kilometers (120 miles) above the crater, provides 8.7 times higher spatial resolution. The change in appearance is dramatic, details in the craters on the south rim are clearly visible and the patterns in brightness variation on the north wall are easily discerned. However, there are only the vaguest hints of boulders on the surface. The picture at lower left was taken June 14 from 44 kilometers (27 miles)above the crater, and the picture at lower right was taken July 19 from 32 kilometers (20 miles) above the crater. These views provide 4.4 and 6times higher spatial resolution than in the view at upper right. Again, the increase in spatial resolution reveals a new level of detail. Boulders have become easily visible, as have fine, dark streaks pointed downslope within the bright material. Variations in brightness also appear at even smaller spatial scales than could be seen before. When NEAR Shoemaker flies to within 5.3 kilometers (3 miles) of Eros' surface on October 26, spatial resolution will increase by another 4 to 6times compared to the two lower views shown here. A whole new level of detail in the shapes of rocks and patterns of brightness variation will be visible - and features not yet seen at all may be revealed. 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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The Ups and Downs of Eros
PIA03111
Sol (our sun)
Multi-Spectral Imager
| Title |
The Ups and Downs of Eros |
| Original Caption Released with Image |
While NEAR Shoemaker does not directly measure gravity on Eros' surface, the spacecraft gathers other data that allow scientists to infer this measurement. Radio tracking has been analyzed to determine the asteroid's gravitational "pull" on the orbiting spacecraft. The many images of the asteroid, plus range measurements from the laser altimeter, measure the body's shape. Comparisons of the shape with the gravitational pull felt by the spacecraft from different parts of its orbit show that the density of the interior must be nearly uniform. The asteroid's shape, density and spin combine to create a bizarre pattern of what is "uphill" and "downhill." In this view, a map of "gravitational topography" has been painted onto a shape model. Red areas are "uphill" and blue areas are "downhill." A ball dropped onto one of the red spots would try to roll across the nearest green area to the nearest blue area. 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' Angular Eastern End
PIA03106
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros' Angular Eastern End |
| Original Caption Released with Image |
NEAR Shoemaker captured this view of Eros' eastern hemisphere on September 9, 2000, from an orbital altitude of about 100 kilometers (62 miles). The spacecraft is in a high enough orbit to "see" the overall global shape of Eros as it did earlier in the mission, but from a different perspective. The eastern end's blocky, angular appearance likely results from large impacts suffered by Eros early in its history. The image also shows several long ridges and a cluster of boulders. The entire scene is about 4 kilometers (2.5 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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Eros Closest Approach Mosaic
PIA03119
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros Closest Approach Mosaic |
| Original Caption Released with Image |
This image mosaic was taken in the early hours of October 26, 2000, as NEAR Shoemaker made its low-altitude flyover of Eros. At the time of closest approach, the camera was looking at a region just 6.4 kilometers (4 miles) away. Much of the surface is covered in rocks of all sizes and shapes, set on a gently rounded surface. Other regions are smooth, suggesting accumulation of fine regolith. The smallest rocks seen are about 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. |
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Eros Map and Place Names
PIA03117
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros Map and Place Names |
| Original Caption Released with Image |
This simple cylindrical projection of an image mosaic of Eros is labeled with proposed names for most of the larger features on the asteroid. Because the images in the mosaic cover an irregularly-shaped object viewed under greatly varying lighting and viewing geometries, it is not possible to match boundaries of images perfectly. The names shown here permit those studying the asteroid to have a consistent "geography" for reference. The theme of the names is famous lovers from history and fiction, taken from different cultures. The name of the largest feature, Himeros, comes from Greek mythology for personification of the longing of love and an attendant 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' Battered Surface
PIA03125
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros' Battered Surface |
| Original Caption Released with Image |
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. |
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Looking Along the Southern H
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PIA03105
Sol (our sun)
Multi-Spectral Imager
| Title |
Looking Along the Southern Hemisphere of Eros |
| Original Caption Released with Image |
The camera on NEAR Shoemaker caught this long view of Eros' southern hemisphere during a stereo imaging sequence on September 6, 2000, from an orbital altitude of 101 kilometers (63 miles). This view adds context to high-resolution images taken from lower orbits with "footprints" only one-fourth to one-third the size. Craters shown in the left foreground of the image are about 1.3 kilometers (0.8 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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Tracking a Feature on Eros
PIA03115
Sol (our sun)
Multi-Spectral Imager
| Title |
Tracking a Feature on Eros |
| Original Caption Released with Image |
One of the strategies for characterizing the small-scale surface features on Eros is to photograph the same features under different lighting. Pictures taken with the Sun high in the sky show variations in the brightness of surface materials, while those taken when the Sun is low in the sky show morphology. Under a low Sun, the asteroid's rotation moves the direction of illumination, and linear features with different orientations are highlighted at different geometries. A way to combine these measurements is in a "feature track," during which NEAR Shoemaker's camera is trained on a single site while the Sun moves through the sky. These four pictures were taken 18 minutes apart on October 7, 2000, during a feature track aimed at the inside of Eros' saddle region. The spacecraft was orbiting at an altitude of 103 kilometers (64 miles). Each frame is about 4.7 kilometers (2.9 miles)across. Variations in surface brightness are most conspicuous in the top two frames, whereas shallow grooves trending from the lower right to upper left are most easily seen in the bottom frames. 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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The Shape of Eros
PIA03113
Sol (our sun)
Multi-Spectral Imager
| Title |
The Shape of Eros |
| Original Caption Released with Image |
NEAR Shoemaker images provided the first model of Eros' shape, shown in this picture. An accurate model of Eros' shape helps the NEAR team determine the asteroid's key properties. The total space enclosed by the surface of the shape model represents the asteroid's estimated volume. The asteroid's mass (determined using NEAR Shoemaker's radio tracking) is divided by its volume to yield an estimate of its density - which is valuable for understanding what kind of rock makes up the interior. The shape also provides information about the distribution of mass below the surface, which scientists use to calculate surface gravity and thus the directions and steepness of slopes. The positions of more than 2,000 landmarks on Eros were determined from more than 12,000 stereo measurements that generate a "grid" of points lying on the asteroid's surface. The shape model is a mathematical representation of the surface passing through all those points. The views at upper left, lower left and lower right show the shape model from over the equator (at 270 and 180 degrees west longitude) and the north pole (90north latitude), respectively. The shape model at upper right is overlain on an image acquired during approach to 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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A Road map for Eros
PIA03112
Sol (our sun)
Multi-Spectral Imager
| Title |
A Road map for Eros |
| Original Caption Released with Image |
These four image mosaics of Eros illustrate the reference system the NEAR team uses to locate points on the asteroid's surface. Choosing from a variety of systems, the team members use latitude and longitude as their directional guide. Latitude is the angle between the equatorial plane and a line connecting the surface point with the center of the body. By convention, the north pole is +90 degrees, the equator is 0 degrees, and the south pole is -90 degrees. Longitude is the angle around the rotational axis separating the point on the surface from the "prime meridian." The prime meridian selected by NEAR scientists is drawn though a large, bright crater at one end of Eros (indicated by an arrow in the lower left mosaic). Again by convention, "west longitude" is used for most planetary bodies, including Eros, and it increases west from the prime meridian. 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 at Closest Approach
PIA03118
Sol (our sun)
Multi-Spectral Imager
| Title |
Eros at Closest Approach |
| Original Caption Released with Image |
This image was taken in the early hours of October 26, 2000, near the closest approach of NEAR Shoemaker's low-altitude flyover of Eros. At that time, the spacecraft's digital camera was looking at a region just 7 kilometers (4.3 miles) away, about 350 meters (1,150 feet) across. Most of the scene is covered in rocks of all sizes and shapes, but the floors of some craters are smooth, suggesting accumulation of fine regolith. For scale, the large boulder just below and to the right of the center of the picture is about 15 meters (50 feet) across. The smallest visible rocks are about 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. |
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