[meteorite-list] NEAR Mission Could Be Extended

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 09:41:10 2004
Message-ID: <200102132303.PAA05765_at_zagami.jpl.nasa.gov>

http://www.space.com/scienceastronomy/solarsystem/near_extension_010213.html

Asteroid Landing Mission Could Be Extended
By Leonard David
space.com
13 February 2001

NASA is studying an option to continue operating the NEAR Shoemaker probe on
asteroid Eros 433 for an extended period, beyond the February 14 cutoff date
that had been planned earlier.

"An option is to continue running on the surface from 7 to 10 days," said
Don Savage, a NASA spokesperson.

An announcement on whether the mission will be extended is set for 1 p.m.
[EST] Wednesday at the Applied Physics Laboratory, which operates the mission for
NASA. Engineers and scientists there also will announce a decision on
whether to relaunch the spacecraft for a brief photo cruise across the
asteroid's surface.

SPACE.com will offer full coverage of the news conference, including
streaming video, starting at 1 p.m.

Scientists are delighted with the high-quality, close-up images of Asteroid
433 Eros that NEAR Shoemaker spacecraft transmitted as it floated to a
historic landing on the rocky surface nearly 200 million miles (322 million
kilometers) from Earth on Monday, February 12.

NEAR Shoemaker was not equipped with landing gear for the first-ever,
odds-against spacecraft rendezvous with an asteroid. The daring dive was
called for as the spacecraft's mission drew toward an anticipated close,
with the mission out of money, the spacecraft out of fuel and NASA initially
denying more "listening time" on its network of deep space radio antennae.

Now there is talk of gathering more data and extending the mission, with the
operational probe already sitting on the surface of an asteroid.

Possibly to be kept in operation at a low data rate is the X-ray/Gamma-Ray
Spectrometer (XGRS) that is onboard the parked spacecraft, Savage said.

Monies to operate the spacecraft for the longer period would come out of
reserves built into the mission, Savage said.

Relaunch decision unclear

Relaunch of the spacecraft from Eros, allowing it to fire its thrusters a
final time to skim across the asteroid's surface and take more close-up
images, was still under discussion through Tuesday.

"A number of options are out there and we expect to hear and review all of
them soon," Savage told SPACE.com.

Telemetry has been received from the probe. All indications are that onboard
equipment is functioning well. The craft's solar panels are soaking up
plenty of power.

A command that was input into the spacecraft prior to touchdown -- a
sequence that would have fired off the probe's engines on Wednesday -- was
disabled shortly after landing, said Michael Buckley, a spokesman for APL.

"Right now, we're trying to assess how healthy the spacecraft is and what
can be done to obtain more telemetry, and more information from NEAR
Shoemaker," Buckley told SPACE.com.

According to sources close to the project, the option to blast off from Eros
is being heavily discussed. New data on remaining fuel onboard the craft is
being assessed. Early indications are, however, that little fuel remains to
attempt the liftoff.

If enough fuel were available, due to the asteroid's weak gravity field,
NEAR Shoemaker could hop high over Eros while snapping yet more images,
according to SPACE.com sources.

NEAR team spokeswoman Helen Worth told one online space site that it was
"highly unlikely" the relaunch attempt will be made.

A similar type maneuver was done in the 1960's with the robotic Surveyor
moon lander.

On November 17, 1967, ground controllers fired Surveyor VI's engines for 2.5
seconds. The craft lifted off the lunar surface and moved a short distance
from the original landing site within the Moon's Sinus Medii region. The
craft moved all of 8 feet (2.4 meters) from its first touchdown spot.

Other final decisions on what can be done with a still-working NEAR
Shoemaker are to be detailed at the news conference tomorrow.
Received on Tue 13 Feb 2001 06:03:35 PM PST