BY JUSTIN RAY
February 17, 2000 -- Follow the NEAR spacecraft's orbit insertion around asteroid 433 Eros. Reload this page for the very latest on the mission.
THURSDAY, FEBRUARY 17, 2000
MONDAY, FEBRUARY 14, 2000
Preliminary data shows the capture orbit features a periapsis, or low point, of plus or minus 49 km to the expected 327 km, an apoapsis, or high point, of plus or minus 67 km to the expected 450 km and period of plus or minus a half-day of the expected 27.6 days. What appears to be a large uncertainty in these numbers is caused by the unknowns about Eros' mass. Researchers say the understanding of the mass will be improved over the next few days, allowing the precise orbit achieved around the space rock to be refined.
NEAR has returned the first batch of images of Eros since the orbit insertion. Also, data collected from the overnight observations asteroid's northern hemisphere using NEAR's infrared spectrometer has been transmitted to Earth.
See the first image of Eros taken after orbit insertion.
Overall, the NEAR spacecraft is in good health almost four years since it was launched into space.
NASA plans to hold an early science results news conference on Thursday at 1800 GMT (1 p.m. EST).
1600 GMT (11:00 a.m. EST)
Accelerometer data from NEAR is now being received on Earth from the spacecraft. It appears there was a very small under-burn, but nothing of concern.
In about an hour, the spacecraft will begin taking additional observations of the asteroid to determine the precise orbit NEAR achieved around Eros.
A press conference is planned for 1900 GMT (2 p.m. EST) today.
1556 GMT (10:56 a.m. EST)
1551 GMT (10:51 a.m. EST)
1550 GMT (10:50 a.m. EST)
1544 GMT (10:44 a.m. EST)
1540 GMT (10:40 a.m. EST)
1535 GMT (10:35 a.m. EST)
1530 GMT (10:30 a.m. EST)
1520 GMT (10:20 a.m. EST)
NEAR had an engine abort in December 1998, causing the craft to miss Eros during the first encounter attempt. Controllers sent NEAR through a U-turn, setting up for today's historic event and saving the mission.
1510 GMT (10:10 a.m. EST)
NASA has approved four additional missions for launch over the next few years.
1500 GMT (10:00 a.m. EST)
The NEAR spacecraft is currently operating through a computer sequence that was loaded aboard the satellite quite some time ago. At this point, controllers say they are just watching and don't have much to do.
1430 GMT (9:30 a.m. EST)
Controllers at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, report NEAR is in the proper attitude for the one-minute maneuver expected to begin at 1533 GMT (10:33 a.m. EST).
The rendezvous sequence was started by NEAR at 0700 GMT (2 a.m. EST) on Sunday. This program includes a unique low-phase flyby of Eros. About five hours ago, the spacecraft flew directly between the sun and Eros, allowing NEAR's infrared spectrometer to obtain observations of the asteroid's northern hemisphere under near-perfect lighting conditions. These observations were aimed at studying Eros' mineral composition.
The upcoming orbit insertion will occur when NEAR is about 207 miles from the center of Eros. The engine firing will slow the craft to allow the asteroid's weak gravity field to capture NEAR.
Officials expect to confirm a succesful orbit around Eros no later than 1630 GMT (11:30 a.m. EST).
First orbit image - NEAR's first view of Eros after entering orbit around the asteroid.
Encounter Preview - background about NEAR's arrival at asteroid 433 Eros.
Eros' Heart - NEAR captures a heart-shaped object on asteroid Eros.
Road to Eros - montage of images show the asteroid from NEAR during approach over the past three weeks.
Dr. Robert Farquhar, the NEAR mission director, announces the spacecraft has entered orbit around asteroid 433 Eros.
PLAY (218k, 20sec QuickTime file)
Mission director Dr. Robert Farquhar describes the ultimate fate of the NEAR once the one-year scientific mission is completed at Eros.
PLAY (399k, 58sec QuickTime file)
U.S. Senator Barbara Mikulski (D-Md) explains why federal tax money was spent on the NEAR mission.
PLAY (440k, 1min, 42sec QuickTime file)
Animation shows the NEAR spacecraft encountering 433 Eros and firing its thrusters to begin orbiting the asteroid.
PLAY (168k, 28sec QuickTime file)
The infrared spectrometer aboard NEAR will be used to determine the asteroid's mineral composition as seen in animation.
PLAY (228k, 37sec QuickTime file)
Dr. Andrew Cheng, NEAR's project scientist, explains what experiments the spacecraft will conduct once it arrives at Eros.
PLAY (311k, 44sec QuickTime file)
Dr. Naom Izenberg, NEAR's instrument scientist, describes how the spacecraft will explore the early history of our solar system.
PLAY (267k, 30sec QuickTime file)
Download QuickTime 4 software to view this file.
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