NEAR Shoemaker's Silent Treatment
12/12/02
Even though the NEAR Shoemaker spacecraft had exceeded every mission expectation, the NEAR team had one
final request of the hearty spacecraft: contact us just one more time. But NEAR Shoemaker - the first
spacecraft to orbit, land on and send data from the surface of an asteroid - didn't respond despite a 12-hour
effort to communicate with it.

NEAR Shoemaker's Descent
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"The exercise was an experiment to see how robust the spacecraft, its instrumentation and subsystems were,
given the extremely cold temperature it has been in for nearly two years," says NEAR Mission Director Robert
Farquhar. "We didn't hold out much hope but we had an opportunity to establish an important data point and
didn't want to lose the chance."
The attempt was initiated at 2:40 p.m. EST, Tuesday, Dec. 10, by the NEAR mission operations team at the Johns
Hopkins University Applied Physics Laboratory, which managed the mission and built the spacecraft, and the Deep
Space Network team, which supported the effort through their 70-meter Goldstone, CA antenna. With asteroid Eros
only about 86 million miles (138 million kilometers) from Earth - less than half the distance it was when NEAR
Shoemaker landed on it in February 2001 - and NEAR Shoemaker's solar panels basking in sunlight for the past three
months, the timing was ideal.
First, operators listened passively for a carrier signal from the spacecraft. Then they sent commands asking NEAR
Shoemaker to transmit data indicating it had survived the last 22 months on the asteroid's surface, despite temperatures
that dipped as low as minus 170 degrees Celsius (-274 degrees Fahrenheit) and long periods of total darkness.
Not knowing which of NEAR Shoemaker's two computers had access to its transmitter, mission operators tried sending
commands to one, then the other. Then they waited -- in vain -- to receive data.
Farquhar says the team will probably never know precisely why NEAR Shoemaker did not respond and they do not expect
to try again.
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