(From west to east)

• Juno is in the constellation of Cetus.
• Melpomene is in the constellation of Cetus.
• Vesta is in the constellation of Leo.
• Herculina is in the constellation of Coma Berenices.
• Pallas is in the constellation of Virgo.

• Information about the Minor Planets can be found at the Minor Planet Observer website.

"Though there are no plans to investigate whether Saturn's moon Titan has a Santa Claus, NASA's Cassini will zoom close to Titan's north pole this weekend. The flyby, which brings Cassini to within about 960 kilometers (600 miles) of the Titan surface at 82 degrees north latitude, will take place the evening of Dec. 27 Pacific time, or shortly after midnight Universal Time on Dec. 28.

The encounter will enable scientists to gather more detail on how the lake-dotted north polar region of Titan changes with the seasons. Scientists will be using high-resolution radar to scan the large and numerous lakes in the north polar region for shape-shifting in size and depth. The ion and neutral mass spectrometer team will take baseline measurements of the atmosphere to compare with the moon's south polar region when Cassini flies by that area on Jan. 12. Cassini will also be collecting images for a mosaic of a bright region called Adiri, where the Huygens probe landed nearly five years ago.

Cassini will have released the Huygens probe exactly five years and three days before this latest flyby. Huygens began its journey down to Titan on the evening of Dec. 24, 2004 California time, or early Dec. 25 Universal Time, and reached the surface Jan. 14, 2005.

Cassini last flew by Titan on Dec. 11, 2009 Pacific time, or Dec. 12 Universal Time. Although this latest flyby is dubbed "T64," planning changes early in the orbital tour have made this the 65th targeted flyby of Titan."

Cassini Imaging Team

"The new year approaches with New Horizons zooming past another milestone: the NASA spacecraft is now closer to target planet Pluto than its home planet, Earth.

"This is the first of several milestones over the next 10 months that mark the halfway points in our journey to the solar system's frontier, where Pluto lies. We on the mission team know we will have a long way to go, but are proud to have brought the spacecraft to this important mile marker in our journey across the entirety of our solar system," says New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute.

Nearly four years after lifting off from Cape Canaveral Air Force Station, Fla., on Jan. 19, 2006, the speedy probe is now approximately 1.527 billion miles (2.463 billion kilometers) from Earth -- and 1.526 billion miles (nearly 2.462 billion kilometers) from the Pluto system. The spacecraft is just a little past halfway between the orbits of giant planets Saturn and Uranus, getting closer to Pluto at the rate of about 750,000 miles (1.2 million kilometers) per day. But closest approach to Pluto is still just over 5½ years away, on July 14, 2015."

New Horizons gallery

"ASTEROID BELT -- NASA's Dawn spacecraft re-entered our solar system's asteroid belt today, Nov. 13, and this time it will stay there.

Dawn first entered the belt (whose lower boundary may be defined as the greatest distance Mars gets from the sun (249,230,000 kilometers, or 154,864,000 miles) in June 2008. It remained within the belt for 40 days before its carefully planned orbital path brought it below the asteroid belt's lower boundary.

This time around, Dawn's flight path will remain above this hypothetical lower boundary for the rest of the mission and for the foreseeable future - Dawn will become the first human-made object to take up permanent residence in the asteroid belt."

"NASA's MESSENGER mission team and cartographic experts from the U. S. Geological Survey have created a critical tool for planning the first orbital observations of the planet Mercury -- a global mosaic of the planet that will help scientists pinpoint craters, faults, and other features for observation. The map was created from images taken during the MESSENGER spacecraft's three flybys of the planet and those of Mariner 10 in the 1970s. A presentation on the new global mosaic is being given today at the Fall Meeting of the American Geophysical Union in San Francisco."

"NASA's Mars Odyssey orbiter put itself into a safe standby mode on Saturday, Nov. 28, and the team operating the spacecraft has begun implementing careful steps designed to resume Odyssey's science and relay operations within about a week."

"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 THEMIS."

Daily Mars Odyssey THEMIS Images
Can be found at the Thermal Emission Imaging System (THEMIS) website.

The Odyssey data are available through a new online access system established by the Planetary Data System.

SPIRIT UPDATE: Surprise from Right-Front Wheel - sols 2111-2117, Dec. 10-16, 2009:

"Spirit remains embedded in the location called "Troy" on the west side of Home Plate. Because of continuing problems with the right-rear wheel, a test of the right-front wheel was done on Sol 2113 (Dec. 12, 2009) to gain insight into the signature for a failed wheel. The right-front wheel had become inoperable back on Sol 779 (March 13, 2006). Surprisingly, the right-front wheel indicated normal motor continuity.

The project also discovered a change in what is known as the single-point ground. A negative voltage is present where no voltage should be. This suggests some sort of electrical short to the rover chassis. The behavior of this single-point ground correlates with the onset of problems with the right-rear wheel and with usage of any of the mobility actuators. This suggests that the rover's motor controller board is suspect.

The right wheels were tested again and driven as part of an extrication maneuver on Sol 2117 (Dec. 16, 2009). The right-front wheel functioned normally for the first three steps of the drive and stopped working during the last step, completing about 10 wheel revolutions. The right-rear wheel did not move at all. The rover only moved slightly during this drive. The project is continuing the investigation of these electric and wheel problems and continuing to explore the functionality of the right-front wheel.

As of Sol 2117 (Dec. 16, 2009), Spirit's solar-array energy production is down to 277 watt-hours, with an atmospheric opacity (tau) of 0.503 and a dust factor of 0.557. Total odometry is 7,730.01 meters (4.80 miles)."

OPPORTUNITY UPDATE: Preparing to Grind - sols 2091-2096, Dec. 11-16, 2009:

"Opportunity has been investigating the rock known as "Marquette Island," which has been of great interest. Assessments of its composition suggest that it might be ejecta from deep within Mars.

The plan is to position the rover to be able to perform a rock abrasion tool (RAT) grind on an accessible surface target on Marquette. On Sol 2093 (Dec. 13, 2009), Opportunity drove about 10 meters (33 feet) around the rock to position an accessible rock surface within reach of the robotic arm (instrument deployment device, or IDD). On Sol 2095 (Dec. 15, 2009), the rover performed a 5-centimeter (2-inch) bump to set up for RAT grinding.

The elevation mirror shroud of the miniature thermal emission spectrometer (Mini-TES) is being opened when appropriate with the expectation of eventual dust cleaning. No dust cleaning of the Mini-TES mirror has been noted yet.

As of Sol 2096 (Dec. 16, 2009), Opportunity's solar-array energy production is 354 watt-hours, with an atmospheric opacity (tau) of 0.462 and a dust factor of 0.528. Total odometry is 18,927.56 meters (11.76 miles)."

Landing sites

"PASADENA, Calif. -- Researchers are receiving new science data from NASA's Mars Reconnaissance Orbiter after the spacecraft's six science instruments resumed observations today.

Observations had been suspended since a computer reset Aug. 26. During the time since then, engineers analyzed a series of previous computer resets by the spacecraft and completed preventive care to guard against a vulnerability identified by that analysis.

In addition to the Aug. 26 event, the orbiter had spontaneously reset its computer three times earlier this year: Feb. 23, June 4 and Aug. 6. The mission had returned to full science operations within a few days after the first three. The decreasing intervals between the resets prompted the team to perform a more extensive analysis after the fourth one."

MARS RECONNAISSANCE ORBITER HIRISE IMAGES
All of the HiRISE images are archived here.