Thursday, November 24, 2011

ESA Contacts Phobos-Grunt


An artist's concept of the Phobos-Grunt orbiter and lander system. Image source: Lavochkin Association via ESA.

Roscosmos lost contact with the Phobos-Grunt spacecraft two weeks ago, the latest in a series of setbacks for the Russian space agency.

The European Space Agency has announced that it briefly established communications contact with the spacecraft on November 22, and two-way contact on November 23.

"The first pass was successful in that the spacecraft's radio downlink was commanded to switch on and telemetry was received," said Wolfgang Hell, ESA's Service Manager for Phobos–Grunt.

Telemetry typically includes information on the status and health of a spacecraft's systems.

"The signals received from Phobos–Grunt were much stronger than those initially received on 22 November, in part due to having better knowledge of the spacecraft's orbital position."

The second pass was short, and so was used only to uplink commands – no receipt of signal was expected.

However, the following three passes in the early morning of 24 November proved to be more difficult: no signal was received from Phobos–Grunt.


According to the release, an early theory is that part of the spacecraft's communications system is not working. More contact opportunities will occur tonight and tomorrow as the craft passes over Perth, Australia.



UPDATE November 24, 2011 7:30 PM ESTThe Russian state-owned news agency RIA Novosti reports:

Russian specialists have deciphered telemetry data received from a wayward Mars probe, but have yet to find out the cause of its erratic behavior, a space industry source said on Thursday.

“Some data” on the spacecraft’s condition were obtained, but it was not yet clear how “functional” it was, the source said ...

Experts say the Mars mission has failed because the last “window of opportunity” for sending the probe to Mars closed on Monday. However, telemetric data from the spacecraft could help identify the causes of the failure and make adjustments for future interplanetary missions.




UPDATE November 25, 2011The European Space Agency reports it was unable to re-establish contact last night with Phobos-Grunt.

Despite listening intently during four scheduled communication passes during the night of 24–25 November, ESA's 15 m-diameter dish antenna at Perth, Australia, did not receive any signals ...

One piece of positive news: observations from the ground indicate that the orbit of Phobos–Grunt has become more stable.

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