SPIRIT UPDATE: Spirit Continues Work Even As Martian Winter Deepens - sol 867-873, June 21, 2006:
Spirit continues to be productive, even as winter conditions harshen. Spirit now receives about one-third as much solar energy as the rover received in mid-2005 while on "Husband Hill." That is, the rover now receives about 310 watt-hours per Martian day, or sol, compared with 900 watt-hours per sol last summer. (A hundred watt-hours is the amount of electricity needed to light one 100-watt bulb for one hour.) The power supply limits how much work Spirit can do each sol. Even so, Spirit acquired two more columns of the "McMurdo panorama" plus a mosaic of microscopic images of a third layer of soil in a target known as "Progress 3." In addition, Spirit completed six targeted studies using the miniature thermal emission spectrometer, all while the rover was also communicating with the Odyssey spacecraft during its overhead pass.
The rover team also planned to begin sending new flight software, known as version R9.2, to Spirit. Two previous flight-software upgrades were sent solely via Spirit's high-gain, X-band antenna. The new uplink plan, however, calls for use of both X-band and UHF antennas because X-band communications with Spirit are often unavailable due to use of that frequency to support NASA's Mars Reconnaissance Orbiter during its aerobraking around the planet.
Sol-by-sol summaries:
Sol 867 (June 11, 2006): Spirit acquired the first portion of column 20 (a one-by-two mosaic) of the McMurdo panorama.
Sol 868: Spirit completed a "photon transfer calibration" of the front hazard-avoidance cameras. This procedure is designed to measure electronic noise (unwanted signals) picked up by imaging sensors that convert light into electrical current in the rover's cameras.
Sol 869: Spirit acquired the second portion of column 20 (a one-by-three mosaic) of the McMurdo panorama. The rover made targeted observations with the miniature thermal emission spectrometer on rock targets nicknamed "Riquelme" and "Zucchelli" while communicating with the Odyssey spacecraft as it passed overhead.
Sol 870: Spirit acquired microscopic images of the soil target known as "Progress 3" and made remote observations of the sky and ground using the miniature thermal emission spectrometer.
Sol 871: Spirit acquired images of the rock abrasion tool and spent 60 minutes communicating with Odyssey while conducting remote observations of rock targets nicknamed "Law-Ricovita," "Tor," "Scott Base," and "Arctowski" using the miniature thermal emission spectrometer.
Sol 872: Plans called for transmission of new flight software, version R9.2, to Spirit.
Sol 873 (June 17, 2006): Plans called for Spirit to acquire super-high-resolution images of a rock target known as "Korolev" using the panoramic camera.
Odometry:
As of sol 869 (June 13, 2006), Spirit's total odometry remained at 6,876.18 meters (4.27 miles).
