(From west to east)

• Vesta is in the constellation of Sagittarius.
• Pallas is in the constellation of Aquarius.
• Amphitrite is at opposition on the 17th in the constellation of Taurus.
• Flora is at opposition on the 18th in the constellation of Taurus.
• Eunomia is in the constellation of Gemini.
• Information about the Minor Planets can be found at the Minor Planet Observer website.

"New HorizonsÕ voyage through the Jupiter system earlier this year provided a birdÕs-eye view of a dynamic planet that has changed since the last close-up looks by NASA spacecraft. A combination of trajectory, timing and technology allowed it to explore details no probe had seen before, such as lightning near the JupiterÕs poles, the life cycle of fresh ammonia clouds, boulder-size clumps speeding through the planetÕs faint rings, the structure inside volcanic eruptions on its moon Io, and the path of charged particles traversing the previously unexplored length of the planetÕs long magnetic tail."

"NASA's Dawn spacecraft successfully completed the first test of its ion propulsion system over the weekend. The system is vital to the success of Dawn's 8-year, 4.9 billion-kilometer (3-billion-mile) journey to asteroid Vesta and dwarf planet Ceres.

'Dawn is our baby and over the weekend it took some of its first steps," said Dawn project manager Keyur Patel of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We have two months more checkout and characterization remaining before Dawn is considered mission operational, but this is a great start.'"

• All of the Mars Global Surveyor images are archived here.

Information about how to submit requests is online at the new Mars Orbiter Camera Target Request Site, at http://www.msss.com/plan/intro"

Newly-released MOC images can be seen in the MOC Gallery, a website maintained by Malin Space Science Systems, the company that built and operates MOC for the Jet Propulsion Laboratory and NASA.

"NASA's Mars Odyssey spacecraft has discovered entrances to seven possible caves on the slopes of a Martian volcano. The find is fueling interest in potential underground habitats and sparking searches for caverns elsewhere on the Red Planet.

Very dark, nearly circular features ranging in diameter from about 100 to 250 meters (328 to 820 feet) puzzled researchers who found them in images taken by NASA's Mars Odyssey and Mars Global Surveyor orbiters. Using Mars Odyssey's infrared camera to check the daytime and nighttime temperatures of the circles, scientists concluded that they could be windows into underground spaces.

Evidence that the holes may be openings to cavernous spaces comes from the temperature differences detected from infrared images taken in the afternoon and in the pre-dawn morning. From day to night, temperatures of the holes change only about one-third as much as the change in temperature of surrounding ground surface.

"They are cooler than the surrounding surface in the day and warmer at night," said Glen Cushing of the U.S. Geological Survey's Astrogeology Team and of Northern Arizona University, Flagstaff, Ariz. "Their thermal behavior is not as steady as large caves on Earth that often maintain a fairly constant temperature, but it is consistent with these being deep holes in the ground."

"A simulated fly-through using the newly assembled imagery is available online.

The fly-through plus tools for wandering across and zooming into the large image are at http://themis.asu.edu."

Mars Odyssey THEMIS Images
Thermal Emission Imaging System (THEMIS) website: http://themis.asu.edu/

October 22-26, 2007

The following new images from the Mars Odyssey spacecraft are now available:

• Many Channels (Released 22 October 2007)
  
• Arsia Flows (Released 23 October 2007)
  
• Back In View (Released 24 October 2007)
  
• Aurorae Chaos (Released 25 October 2007)
  
• Sirenum Fossae (Released 26 October 2007)
  
• All of the THEMIS images are archived here.

The Odyssey data are available through a new online access system established by the Planetary Data System at: http://starbrite.jpl.nasa.gov/pds/"

Spirit Status: Spirit Considers Options for Surviving Another Winter on Mars - sol 1348-1354, October 30, 2007

"Spirit's handlers are currently confronted with the decision of where to send the rover for the winter. Dust deposition on the rover's solar panels, a product of the recent dust storms, has made power predictions for the upcoming winter even worse than those experienced during Spirit's last Martian winter. Members of the science team hope to find a place where Spirit can achieve a tilt of 20 degrees or more toward the north, facing the sun.

During the week, Spirit drove approximately 50 meters (164 feet) in a southerly and southeasterly direction toward a potential off-ramp from the top of the elevated plateau known as "Home Plate."

Proposed locations for a winter haven include driving south down the off-ramp and making a break for "von Braun," a hill approximately 120 meters (390 feet) away; heading north across Home Plate and driving down the north-facing edge; or driving west of Home Plate to a hill tentatively identified as "West Knob."

On sols 1349 and 1351 (Oct. 19 and Oct. 21, 2007), Spirit acquired long-baseline stereo images of von Braun, to the south of Home Plate.

Spirit has been generating approximately 345 watt-hours of solar array energy (enough to run a 100-watt bulb for almost 3 1/2 hours) per Martian day (or sol). Measurements of atmospheric dust opacity, known as Tau, have been approximately 0.7 (higher Tau measurements correspond to more dust)."

Opportunity Status: 'Shaking' Off the Dust and Getting Back to Work - sol 1274-1281, Sep 20, 2007

"The skies continue to clear over the Opportunity site, and the dust is falling from both the sky and the rover. The last week was dedicated to evaluating the payload and assessing dust accumulation on the instruments. Fortunately, the solar array energy has improved to over 350 Watt-hours for the last four sols. This has given the vehicle enough power to support two alpha particle X-ray spectrometer integrations and two Mars Express UHF overflights.

The team began a campaign to recalibrate the panoramic camera tau observations used to measure the level of atmospheric opacity. The recalibration sequences are designed to run at various times of day to get the sun at different angles in the sky. Each sequence has custom exposure durations and color filters tailored to the intended time of execution.

As the team saw last week, the instruments on the robotic arm turret collected a substantial amount of dust during the storm. There are two main concerns: dust inside the alpha particle X-ray spectrometer and dust under the microscopic imager dust cover. On Spirit, dust managed to somehow find its way under the microscopic imager dust cover, so engineers are handling the dust-covered turret on Opportunity with care.

Twice in six sols, the team used the front hazard avoidance camera (and the panoramic and navigation cameras) to image the microscopic imager with the dust cover closed. There were two drives between each set of imaging and there is noticeable cleaning between the two. The first of several sky flats images taken with the microscopic imager (dust cover closed) came down today. Preliminary analysis indicates little to no dust on the lens or dust cover. Next week, the team will determine if it is safe to open the dust cover and take images to see if any dust is on the lens itself.

The first of two alpha particle X-ray spectrometer integrations was received on the ground today and the initial analysis shows little to no dust contamination. Argon peaks are just as large as before, but additional integrations are necessary to complete the analysis. In the meantime, the team modified the robotic arm ready position to face the alpha particle X-ray spectrometer in towards the vehicle's warm electronics box. The hope is that this will prevent any dust from collecting inside."

Landing sites