[meteorite-list] Mars Exploration Rovers Update: March 23 - April 1, 2010

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri, 2 Apr 2010 17:18:07 -0700 (PDT)
Message-ID: <201004030018.o330I7AR005242_at_zagami.jpl.nasa.gov>

http://marsrovers.jpl.nasa.gov/mission/status.html

SPIRIT UPDATE: Spirit in Hibernation - sols 2211-2218, March 23-30,
2010:

The scheduled downlink from Spirit on Sol 2218 (March 30, 2010), via
Ultra-High Frequency (UHF) relay through the Odyssey orbiter was not
received.

Odyssey reported nominal operations for their orbiter, but there was no
received Spirit telemetry and no evidence of a UHF signal from the
surface of Mars at Gusev crater. The team was anticipating Spirit to
experience a low-power fault about this time. So, the most likely
explanation for the missing downlink is that Spirit did go into that
low-power fault taking her batteries off-line, sometime between the last
downlink on Sol 2210 (March 22, 2010), and Sol 2218 (March 30, 2010).

With a low-power fault, Spirit is in a deep sleep with all loads turned
off (no communication) and only the master clock being powered. The
clock will stir Spirit on regular intervals to see if the batteries have
recharged enough to wake up. If not, Spirit will remain deeply sleeping
with the solar arrays trying to charge the rover batteries. The project
had already begun listening for the possible X-band fault
[communication] windows associated with the low-power fault. No X-band
fault window has been detected, yet. The Deep Space Network radio
science receiver (RSR) is being used to search for any X-band signal
from Spirit. The rover will also experience an Uploss timer fault, since
the rover would not be awake for us to reset that timer with a ground
command. When the Uploss timer does expire, Spirit will also be
responsive to UHF relay passes. However, Spirit will only respond with
an X-band fault window or a UHF relay pass, if her batteries have
recharged sufficiently. The team does not expect a response from Spirit
for some time, but will listen every day. Total odometry is unchanged at
7,730.50 meters (4.80 miles).

------------------------------------------------------------------------

OPPORTUNITY UPDATE: Opportunity Drives By Twin Craters - sols
2192-2199, March 25 - April 01, 2010:

Opportunity has been driving, making good progress toward Endeavour
crater. The rover has had to pause between drives to recharge her
batteries because of the diminishing sunlight during the advance into
winter.

On Sol 2193 (March 26, 2010), Opportunity drove about 68 meters (223
feet) towards a pair of highly eroded craters. On the next sol, the
rover performed a drive-by imaging of the twin craters, covering about
55 meters (180 feet). Further driving next to the twin craters was
performed on Sol 2197 (March 30, 2010), getting a good look inside, with
the rover covering about 30 meters (98 feet) of distance. On Sol 2199
(April 1, 2010), Opportunity left the area of the twin craters with a
50-meter (164-foot) drive and resumed her push toward Endeavour, still
many kilometers away. Opportunity will rest from driving on Sol 2200
(April 2, 2010) to recharge her batteries. As of Sol 2199 (April 1,
2010), the solar array energy production was 238 watt-hours with an
atmospheric opacity (tau) of 0.371 and a dust factor of 0.501. Total
odometry is 20,245.20 meters (20.25 kilometers, or 12.58 miles).
Received on Fri 02 Apr 2010 08:18:07 PM PDT