* Astronomy

Blobrana · L

RE: Mars Exploration Rover Spirit

Blobrana · L

Spirit Remains Silent at Troy - sols 2560-2566, March 17-23, 2011:

No communication has been received from Spirit since Sol 2210 (March 22, 2010), over a year ago.
Deep Space Network X-band listening and recovery commanding continue. The project has been systematically conducting commanding over a range of frequencies and over a range of local solar times on Mars. This covers the possibility that the rover's receiver has degraded and/or the clock has drifted significantly since March of 2010.
The project is continuing the commanding of extra-long ultra-high frequency (UHF) relay passes to account for possible rover clock drift or clock error and to make the rover responsive to UHF relay (if it is has experienced a mission-clock fault). The project is also commanding the backup solid-state power amplifier, in case the primary X-band transmitter has failed. Peak solar energy production for Spirit at the Gusev site is estimated to have already occurred back around March 10, 2011.
Total odometry is unchanged at 7,730.50 metres.

Blobrana · L

Alternatives Have Begun in Bid to Hear from Spirit

Hopes for reviving NASA's Spirit Mars rover dimmed further with passage last week of the point at which the rover's locale received its maximum sunshine for the Martian year.
The rover team has tried to contact Spirit for months with strategies based on the possibility that increasing energy availability might wake the rover from hibernation. The team has now switched to communication strategies designed to address more than one problem on the rover. If no signal is heard from Spirit in the next month or two, the team at NASA's Jet Propulsion Laboratory, Pasadena, Calif., will shift to single-rover operations, continuing to operate Spirit's active twin, Opportunity.
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Blobrana · L

NASA Checking on Rover Spirit During Martian Spring

Nine months after last hearing from the Mars rover Spirit, NASA is stepping up efforts to regain communications with the rover before spring ends on southern Mars in mid-March.
Spirit landed on Mars Jan. 4, 2004 (Universal Time; Jan. 3, Pacific Time) for a mission designed to last for three months. After accomplishing its prime-mission goals, Spirit worked for more than five years in bonus-time extended missions.
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Blobrana · L

The odometer on the Mars rover Spirit has been stuck at 4.8 miles for more than 1½ years and has been incommunicado since March.
This double dose of bad luck hangs over the scrappy spacecraft, which marks its seventh year on Mars on Monday.
NASA doesn't know if the Spirit is dead or alive, but it's diligently listening for any peep as the rover remains mired in a sand trap.
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Blobrana · L

NASA Trapped Mars Rover Finds Evidence of Subsurface Water

The ground where NASA's Mars Exploration Rover Spirit became stuck last year holds evidence that water, perhaps as snow melt, trickled into the subsurface fairly recently and on a continuing basis.
Stratified soil layers with different compositions close to the surface led the rover science team to propose that thin films of water may have entered the ground from frost or snow. The seepage could have happened during cyclical climate changes in periods when Mars tilted farther on its axis. The water may have moved down into the sand, carrying soluble minerals deeper than less soluble ones. Spin-axis tilt varies over timescales of hundreds of thousands of years.
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Blobrana · L

NASA's Hibernating Mars Rover May Not Call Home

NASA mission controllers have not heard from the Mars Exploration Rover Spirit since March 22, and the rover is facing its toughest challenge yet -- trying to survive the harsh Martian winter.
The rover team anticipated Spirit would go into a low-power "hibernation" mode since the rover was not able to get to a favourable slope for its fourth Martian winter, which runs from May through November. The low angle of sunlight during these months limits the power generated from the rover's solar panels. During hibernation, the rover suspends communications and other activities so available energy can be used to recharge and heat batteries, and to keep the mission clock running.
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Blobrana · L

SPIRIT UPDATE: Spirit Standing by At Troy - sols 2295-2300, June 17-22, 2010:

Spirit remains silent at her location called "Troy" on the west side of Home Plate. No communication has been received from the rover since Sol 2210 (March 22, 2010).
As stated previously, it is likely that Spirit has experienced a low-power fault and has turned off all sub-systems, including communication and gone into a deep sleep. While sleeping, the rover will use the available solar array energy to recharge her batteries. When the batteries recover to a sufficient state of charge, Spirit will wake up and begin to communicate.
There is the additional risk that the rover may trip a mission clock fault. If that happens, the rover would remain asleep until the batteries have recharged sufficiently and there is enough sunlight on the solar arrays to wake the rover. With the southern winter solstice back on May 13, 2010, solar energy levels and temperatures are expected to be improving.
Total odometry is unchanged at 7,730.50 meters.

Blobrana · L

The Spirit rover, mission designation MER-A (Mars Exploration Rover - A), was launched aboard a Delta II rocket from Cape Canaveral, Florida, on the 10th June, 2003.

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Blobrana · L

SPIRIT UPDATE: Spirit in Energy Saving Mode - sols 2177-2184, February 16-23, 2010:

Spirit is in her winter position, still embedded in the area called "Troy" on the west side of Home Plate. Efforts continue to prepare the rover for winter.
Because of the low power levels, multi-sol plans are being developed with reduced communication activity to save energy. These plans have a single uplink to the rover and few Ultra-High Frequency (UHF) downlinks to return the data. The new long-range UHF communication table is on board and various settings for winter are being prepared.
A special Deep Space Network (DSN) test was performed with Spirit to confirm that even during the time of weakest signal, the DSN should be able to detect the rover's signal with the DSN's Radio Science Receiver (RSR) even if the Mars Reconnaissance Orbiter is transmitting.
As of Sol 2184 (Feb. 23, 2010), the rover solar array energy production was to 163 watt-hours with an atmospheric opacity (tau) of 0.367 and a dust factor of 0.518. Total is 7,730.50 metres.