NASA sends UC Berkeley satellite into orbit
14 January 2002
By Robert Sanders, Media Relations
BERKELEY - A
small UC Berkeley satellite was placed into polar orbit Sunday,
Jan. 12, embarking on a year-long mission to study the hot bubble
of gas that envelops our solar system and nearby stars. The
Cosmic Hot Interstellar Spectrometer satellite (CHIPSat), originally
scheduled for launch on Dec. 19, lifted off from Vandenberg
Air Force Base in California aboard a Boeing Delta II rocket
at 4:45 p.m. PST Sunday.
"It
was spectacular," said CHIPSat team leader Mark Hurwitz, a research
astronomer at UC Berkeley's Space Sciences Laboratory, who watched
it on a computer screen from the Vandenberg Mission Director's
Center. The rocket emerged from the ground-hugging fog and haze
into a clear sky, and 75 minutes after launch released its main
payload, the Ice, Cloud and Land Elevation satellite (ICESat).
The piggybacking CHIPSat separated eight minutes later, at 6:08
p.m. PST. Initial contact with CHIPSat was made at about 98
minutes after launch at 6:23 p.m. PST as the spacecraft passed
over UC Berkeley.
For
now, Hurwitz and his team are waiting for the satellite to stop
tumbling and settle into a stable attitude, essential for proper
pointing and assuring that the solar panels get the best exposure
to the sun. These preliminary steps are being handled at SpaceDev,
Inc., which built the spacecraft housing UC Berkeley's instrument.
"We
want to wait for the attitude control system to take control
of the spacecraft reliably, and then we will start opening instrument
apertures and turning on the detector — probably in two
weeks or so," he said. They could be receiving data within a
month. CHIPSat, though a tiny mission, is a milestone in satellite
operations.
It is the first satellite controlled exclusively through internet
protocols, according to SpaceDev program manager Jeff Janicik.
Using standard internet protocols such as TCP/IP and FTP, controllers
send commands to the spacecraft and receive data.
"Most
missions have a custom-written format for efficiently sending
and receiving blocks of data to download as much data as possible,"
Hurwitz said. "Our data rates are low enough that efficiency
is not a constraint, so using prepackaged communications formats
simplifies design of the whole system."
In
the future, Hurwitz' team should be able to transmit commands
to the spectrograph through SpaceDev and receive data the way
most of us download files through the internet.
For
more on the science behind CHIPSat, check
out a previous story on the satellite.
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