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IMAGE OF ASTEROID 253 Mathilde
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This image mosaic of asteroid 253 Mathilde is
constructed from four images acquired by the NEAR
spacecraft on June 27, 1997.
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Asteroid 253 Mathilde
June 27, 1997
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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.
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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.
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Asteroid 253 Mathilde
June 26, 1997
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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.
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Two different views of asteroid 253 Mathilde were
obtained by the NEAR spacecraft on June 27, 1997.
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Asteroid 253 Mathilde
June 27, 1997
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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 1360. 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 430 (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.
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Mathilde, Gaspra, Ida
Comparison
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These are views of the three asteroids that have been
imaged at close range by spacecraft. The image of
Mathilde (left) was taken by the NEAR spacecraft on June
27, 1997. Images of the asteroids Gaspra (middle) and
Ida (right) were taken by the Galileo spacecraft in 1991
and 1993, respectively. All three objects are presented
at the same scale. The visible part of Mathilde is 59 km
wide x 47 km high (37 x 29 miles). Mathilde has more
large craters than the other two asteroids. The relative
brightness has been made similar for easy viewing;
Mathilde is actually much darker than either Ida or
Gaspra.
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