NASA footage shows asteroid in motion
January 26, 1999
(CNN) -- Humankind will have to wait at least another year to see the first closeup views of an asteroid. But in the meantime, NASA has released some unprecedented footage of one of the mysterious space rocks as it rotates slowly in the solitude of space.
The NEAR spacecraft captured a series of images of 430 Eros as it flew within 2,320 miles (3,830 km) of the asteroid on December 23. Presented in sequence, the images show Eros, a very elongated, cratered object about 18-by-eight miles (30-by-14 km) across, rotating with a period of just over five hours.
The movie shows about two-thirds of a rotation of Eros. The first view, taken at 10:44 a.m. EST from a range of 7,150 miles (11,890 km), shows about half of the dayside of Eros. The movie ends at 2:05 PM EST, just after closest approach, when only a tiny portion of the dayside of Eros is visible.
During the movie, the spacecraft's view of the asteroid changed dramatically. As is the case with most asteroids, Eros is rotating uniformly about a fixed axis, and is not tumbling randomly through space.
NEAR had been scheduled to begin orbiting Eros in February, but the rendezvous was delayed for a year after the spacecraft's main engine shut down during a series of crucial firings on December 20.
In a matter of hours, mission controllers were able to program an alternate command sequence that put the spacecraft on a trajectory about 2,500 miles (4,100 km) from the surface of the asteroid.
However, plans to orbit Eros -- the first such attempt in history -- were postponed until February 2000.
NEAR was one of the first NASA robot crafts built under a program that emphasizes less expensive and more effective ways of exploring the universe. It cost $129 million to build, and the entire mission so far has stayed within its planned budget of $211.5 million.
Launched in February 1996, NEAR is to spend almost a year orbiting within 9 miles (15 km) of the surface of the potato-shaped asteroid.
If the spacecraft succeeds in orbiting Eros, it then is expected to possibly land on its surface.
Scientists hope the mission will provide answers to fundamental questions about the nature and origin of near-Earth objects, such as the numerous asteroids, meteoroids, and comets in the vicinity of Earth's orbit.
Sunday 1:30pm - 2:00pm ET (10:30am - 11:00am PT)
Saturday 1:30pm - 2:00pm ET (10:30am - 11:00am PT)
Back to the top
© 2000 Cable News Network. All Rights Reserved.
Terms under which this service is provided to you.
Read our privacy guidelines.