[meteorite-list] New Communication with Philae - Commands Executed Successfully

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri, 10 Jul 2015 15:14:44 -0700 (PDT)
Message-ID: <201507102214.t6AMEiXN004087_at_zagami.jpl.nasa.gov>

http://blogs.esa.int/rosetta/2015/07/10/new-communication-with-philae-commands-executed-successfully/

New communication with Philae - commands executed successfully
European Space Agency
July 10, 2015

This report is provided by the German Aerospace Center, DLR
http://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10081/151_read-14156/#/gallery/17198

The Philae lander communicated with the Rosetta orbiter again between
19:45 and 20:07 CEST on 9 July 2015 and transmitted measurement data
from the COmet Nucleus Sounding Experiment by Radiowave Transmission
(CONSERT) instrument. Although the connection failed repeatedly after
that, it remained completely stable for those 12 minutes. "This sign of
life from Philae proves to us that at least one of the lander's
communication units remains operational and receives our commands,"
said Koen Geurts, a member of the lander control team at DLR Cologne.

The mood had been mixed over the last few days; Philae had not
communicated with the team in the DLR Lander Control Center (LCC) since
24 June 2015. After an initial test command to turn on the power to
CONSERT on 5 July 2015, the lander did not respond. Philae's team began
to wonder if the lander had survived on Comet 67P/Churyumov-Gerasimenko.

"We never gave up on Philae and remained optimistic," said Geurts. There
was great excitement when Philae "reported in" on 13 June 2015 after
seven months of hibernation and sent data about its health. The lander
was ready to perform its tasks, 300 million kilometres away from Earth.

However, Philae has to communicate with the ground stations through
Rosetta, which acts as a radio relay. Restrictions on the orbiter's
approach to and orbit around the comet have not permitted regular
communication with the lander. The data sent on 24 June did not suggest
that the lander had experienced technical difficulties. Now, Philae's
internal temperature of zero degrees Celsius gives the team hope that
the lander can charge its batteries; this would make scientific work
possible regardless of the "time of day" on the comet.

The received data is currently being evaluated. "We can already see that
the CONSERT instrument was successfully activated by the command we sent
on 9 July," explained Geurts. Even now, Philae is causing the team some
puzzlement: "We do not yet have an explanation for why the lander has
communicated now, but not over the past few days."

The trajectory of the orbiter, for example, has not changed over the
last three weeks. However, one thing is certain; Philae has survived the
harsh conditions on the comet and is responding to commands from the LCC
team. "This is extremely good news for us," said Geurts.

Watch the latest video update from the LCC, here.
https://twitter.com/DLR_en/status/619483893280940032>

Rosetta is an ESA mission with contributions from its Member States and
NASA. Rosetta's Philae lander is contributed by a consortium led by DLR,
MPS, CNES and ASI.
Received on Fri 10 Jul 2015 06:14:44 PM PDT