India's first lunar probe has lost contact with Earth,
and the mission has been declared over more than a year earlier
than intended. It is not yet clear what caused the communications
failure, but mission members suspect it was exacerbated by the
earlier loss of star sensors used to orient the craft.
Chandrayaan-1 launched on 22 October 2008 and was designed to
spend two years mapping the moon.
But on Saturday, after less than 10 months in orbit, the $80
million mission lost contact with radio dishes in Bangalore, India,
used to communicate with it.
"We don't know the exact reason for [the] loss of radio signals,
but as of now it has been declared that the mission is terminated,"
says Deviprasad Karnik, space counsellor at the Embassy of India in
Washington, DC. He said scientists from the Indian Space Research
Organisation (ISRO) "are assembling at Bangalore, and they're going
to try to figure out what went wrong".
Contact with Chandrayaan-1 may have been lost because its
antenna rotated out of direct contact with Earth, Karnik says.
Earlier this year, the spacecraft lost both its primary and back-up
star sensors, which use the positions of stars to orient the
spacecraft.
Joint venture
After the failures, the spacecraft switched to using spinning
gyroscopes to point the probe. It is possible that a glitch with
the gyros could have sent the craft spinning. "The star sensor
played a major role and the loss of that certainly affected the
further management of the spacecraft orientation and orbit," Karnik
told New Scientist.
The loss of Chandrayaan-1 comes less than a week after the
spacecraft's orbit was adjusted to coordinate radar observations
with NASA's Lunar Reconnaissance Orbiter. During the manoeuvre,
Chandrayaan-1 fired its radar beam into a crater on the moon's
north pole. Both spacecraft listened for echoes that might indicate
the presence of water ice – a precious resource for future lunar
explorers.
Despite its shortened lifetime, Chandrayaan-1 met all its
technical milestones and completed 95 per cent of its scientific
objectives by mapping almost all of the lunar surface, Karnik says.
Data from the mission – including more than 70,000 images – are
still being analysed, Karnik says.
India's space agency is also working on the spacecraft's
successor, Chandrayaan-2, which will consist of an orbiter, a
lander, and a rover. India hopes Chandrayaan-2 will reach the moon
by 2013.
If you would like to reuse any content from New Scientist,
either in print or online, please contact the syndication
department first for permission. New Scientist does not own rights
to photos, but there are a variety of licensing options available
for use of articles and graphics we own the copyright to.