(From west to east)

• Vesta is in the constellation of Capricornus.
• Pallas is in the constellation of Aquarius.
• Flora is in the constellation of Taurus.
• Eunomia is at opposition on the 10th in the constellation of Gemini.
• Hebe is in the constellation of Leo.
• Information about the Minor Planets can be found at the Minor Planet Observer website.

"Saturn in the Cassini era has proved to be an unexpectedly colorful place, compared to the browns and golds imaged by the two Voyager spacecraft.

Saturn is headed toward equinox in 2009, followed by springtime in the northern hemisphere. Having a spacecraft in orbit while such changes occur will be of great benefit in scientists' quest to understand the atmospheres of the giant planets.

The planet's oblate, or squashed, shape is clearly visible in this view. The low-density planet rotates so fast (in about 10.5 hours) that it flattens out slightly around its middle. The bluish tint of the northern latitudes is presumed to be a seasonal effect, and will likely disappear entirely as the north receives increasingly greater amounts of sunlight."

Cassini Imaging Team

"The New Horizons spacecraft's spectacular flight past Jupiter earlier this year -- which gave it a gravitational boost on the way to a 2015 encounter with Pluto -- also provided an opportunity to test the instruments on the NASA probe while gathering new scientific data. Members of the New Horizons team will present findings from that encounter during the American Geophysical Union (AGU) Fall Meeting this week in San Francisco.

A combination of technology, trajectory and good timing allowed New Horizons to explore details that no spacecraft had seen before, such as lightning near Jupiter's poles, the life cycle of fresh ammonia clouds in Jupiter's atmosphere, the structure inside volcanic eruptions on Jupiter's planet-sized moon Io, and the path of charged particles traversing the previously unexplored length of Jupiter's long magnetic tail."

"NASA's Dawn spacecraft has successfully completed the initial checkout phase of the mission and begun its interplanetary cruise phase, which is highlighted by nearly continuous thrusting of its ion propulsion system. Dawn is on a 8-year, 3-billion mile journey to asteroid Vesta and dwarf planet Ceres."

• 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.

Artist's concept of Mars Opposition on December 24, 2007. The distances between the sun, the planets, and the distant nebula are not to scale.

"Like all the planets in our solar system, Earth and Mars orbit the sun. But Earth is closer to the sun, and therefore races along its orbit more quickly. Earth makes two trips around the sun in about the same amount of time that Mars takes to make one trip. So sometimes the two planets are on opposite sides of the sun, very far apart, and other times, Earth catches up with its neighbor and passes relatively close to it."

"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/

December 24-28, 2007

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

• Lava Flows (Released 24 December 2007)
  
• Polar Outliers (Released 25 December 2007)
  
• Landslides (Released 26 December 2007)
  
• Dust Devil Tracks (Released 27 December 2007)
  
• Canyon Ridges (Released 28 December 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 Makes It to a North-Facing Slope - sol 1404-1408, December 21, 2007

"Spirit has achieved 13 degrees of northerly tilt after backing the rear and middle wheels over the north edge of "Home Plate," where the rover will remain during the coming holidays. Power levels have already increased significantly from 260 watt-hours on sol 1404 (Dec. 15, 2007) to 291 watt-hours on sol 1408 (Dec. 19, 2007).

Spirit's ideal northerly tilt at present would be 16 degrees, and the rover's handlers plan to have the rover creep farther down the slope in mid-January to increase the northerly tilt. On Spirit's current track, they expect to see an ultimate northerly tilt of 25 degrees to 30 degrees.

In the meantime, Spirit will perform studies using instruments on the rover's robotic arm, including the microscopic imager, alpha-particle X-ray spectrometer, and Mössbauer spectrometer. Spirit's handlers still have a huge challenge ahead, but after three weeks of working on Mars time and on weekends, they are, like the rover, enjoying a long-awaited and well-deserved sigh of relief.

The science team is nicknaming features in the area after the Tuskegee Airmen, the first black pilots to serve in the U.S. military."

Opportunity Status: Opportunity Maneuvers Around Steeper Slopes in "Victoria Crater" - sol 1375-1381, Dec 17, 2007

"Opportunity is now in the process of driving to the third band of light-colored rocks that circumscribe "Victoria Crater" beneath the rim. Scientists had initially planned to have the rover head directly downhill to a rock target nicknamed "Ronov," within the band known as "Lyell." They selected an alternate rock exposure, dubbed "Newell," when engineers determined that the original drive route would tilt the rover 25 degrees, somewhat higher than desired. The estimated tilt along the new route is a much gentler 20 degrees but the drive is somewhat more complex and required two days of planning.

During the past week, Opportunity completed scientific investigation of the second band of rocks, known as "Smith," with an analysis of elemental chemistry and iron-bearing minerals beneath the surface of a rock exposure labeled "Smith2." To do this, the rover collected data with the alpha-particle X-ray spectrometer Mössbauer spectrometer, respectively.

If next week's planned drive goes as anticipated and closer inspection of Newell deems it to be an acceptable target, Opportunity is likely to stay at the new location for several weeks collecting data. Scientists plan to have the rover conduct a complete campaign of studies with the alpha-particle X-ray and Mössbauer spectrometers, microscopic imager, rock abrasion tool, and on-board cameras.

During the planned drive, Opportunity will complete a "Get Quick Fine Attitude," a procedure for determining the rover's position relative to the changing position of the Sun. This activity recalibrates the inertial measurement unit and eliminates tiny errors that accumulate over time in pointing the antenna.

Opportunity is healthy and all subsystems are operating as expected. The latest available power readings, taken on Martian day, or sol, 1379 (Dec. 10, 2007), show solar energy levels at a robust 601 watt-hours, enough to light a 100-watt bulb for 6 hours."

Landing sites