NEAR Shoemaker has entered a new orbit around Eros that will yield even more spectacular high-resolution images and additional information on the asteroid's elemental composition and gravity field.
A short engine burn at 11 p.m. EDT on July 13 set NEAR Shoemaker in a circular orbit just 22 miles (35 kilometers) from Eros' center, giving the satellite its best view yet of the peanut-shaped asteroid.
Before getting to the detailed photos and surface composition readings, the NEAR team will devote the first four days of the 10-day orbit refining its estimate of the asteroid's gravity.
Using NEAR Shoemaker's radio tracking equipment, the team will gather data it needs to design lower-altitude operations later in the mission, and learn more about Eros' internal makeup.
"We're looking for variations in density from one part of the asteroid to another," says NEAR Project Scientist Andy Cheng. "It's not entirely clear whether the density is uniform, so we have to get closer and look harder."
The spacecraft's near-polar orbit will bring it as close as 12 miles (19 kilometers) from the ends of the rotating asteroid. Circling Eros at about 8 miles an hour, NEAR Shoemaker is 71 million miles (114 million kilometers) from Earth.
Upcoming Activities:
In addition to regular Eros Science and Optical Navigation, the following are operationally significant activities planned for the NEAR Shoemaker mission operation:
July 24 Eros Orbit Correction Maneuver 9 (35 km x 50 km transfer orbit)
July 31 Eros Orbit Correction Maneuver 10 (50 km orbit circularization)
Aug 8 Eros Orbit Correction Maneuver 11 (50 km orbit – plane change)
Aug 26 Eros Orbit Correction Maneuver 12 (50 km x 100 km transfer orbit)
Eros at 35 Klicks
NEAR-Shoemaker Operational Status
Laurel – July 17x, 2000 –
Status Report
July 14, 2000 – NEAR Shoemaker has successfully entered a 35 km circular orbit around the asteroid Eros. During this past week, NEAR Shoemaker remained in Operational Mode with Flight Computer #1 and Attitude Interface Unit #2 in control of spacecraft attitude.
Except for the Near-Infrared Spectrometer (NIS), the spacecraft instrument suite remained "ON" and operational this week.
Orbit Correction Maneuver 8 (OCM 8) was successfully executed today, July 14, at 03:00 UTC. This maneuver, performed near periapse of the 35 km x 50 km transfer orbit, placed the NEAR Shoemaker spacecraft in a nominal 35 km circular orbit relative to the center of Eros.
During the 35 km orbit, after recovering opnav data associated with OCM 8, four days will be spent sun-pointing to refine the gravitational field model, and the remaining duration will be allocated to XGRS for prime science data collection.
The next maneuver, scheduled for July 24, is Orbit Correction Maneuver 9 (OCM 9), which initiates a 35 km x 50 km transfer orbit.
Except for the NIS, science activities conducted this week included Eros observations by the full instrument suite: MSI, MAG, XGRS and NLR. Please consult science timelines for more details.
