(From west to east)

• Isis is at opposition on the 8th in the constellation of Aquarius.
• Massalia is in the constellation of Pisces.
• Julia is at opposition on the 10th in the constellation of Pegasus.
• Melpomene is at opposition on the 10th in the constellation of Cetus.
• Vesta is in the constellation of Leo.

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

"Saturn's rings cast a shadow on the moon Janus in this image made possible only around the time of the planet's August 2009 equinox.

Some of the planet's moons cast shadows onto the rings at equinox, but in this image, it's the rings casting shadows on a moon. The shadow obscures part of Janus (179 kilometers, or 111 miles across) in the image. The planet's thin F ring can be seen in the upper left of the image.

See Reciprocating Rings to see the rings casting a shadow on the moon Tethys."

Cassini Imaging Team

"New Horizons sails silently today through another milestone on the way to its historic reconnaissance of the Pluto system, reaching the halfway point between the orbits of Saturn and Uranus.

The NASA spacecraft will reach 14.41 astronomical units from the Sun — 1.34 billion miles, or nearly 14 1/2 times the distance between the Earth and Sun — between 6-7 p.m. EDT "Only five operating spacecraft have ever journeyed this far, and only one — the storied Voyager 2 mission — still had an encounter planned even farther out," says New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute. "New Horizons is on its way to the farthest planetary encounter ever, at just over 32 astronomical units, which is a quarter-billion miles beyond the current planetary encounter record set at Neptune back in 1989."

New Horizons gallery

"Mission controllers at NASA's Jet Propulsion Laboratory in Pasadena, Calif., have received a transmission from the Dawn spacecraft confirming it has re-ignited its ion propulsion system. For those of you scoring at home, Thruster # 1 received the honors. Over the course of its eight-year mission, first to asteroid Vesta and then off to dwarf planet Ceres, Dawn's three ion engines will accumulate 2,000 days of operation."

"MESSENGER's engineering and operations teams convened at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., this morning to confirm the health and readiness of the spacecraft. "All spacecraft sub-systems and instruments reported nominal operations, indicating that MESSENGER was ready for its third encounter with Mercury," said MESSENGER Systems Engineer Eric Finnegan of APL.

At 10:28 a.m. the last bits of data from the spacecraft were received as it transitioned from high-gain downlink to beacon-only operations, turning towards the planet to start the approach tail-sweep sequence with the Mercury Atmospheric and Surface Composition Spectrometer instrument. This morning, the spacecraft returned this image, revealing some of the last areas of terrain not before seen at close range by spacecraft. Higher-resolution images of these areas will be obtained tomorrow when the spacecraft is closer to the planet.

For the next 30 hours, the spacecraft will take repetitive scans through Mercury's comet-like anti-sunward tail, pausing now and then to take a color image and a high-resolution mosaic of Mercury with the Mercury Dual Imaging System instrument."

The probe's third flyby of Mercury next month will take it again over the planet's western hemisphere, and the observations will be used to refine the estimate of the planetary magnetic field, Anderson explains."

"PASADENA, Calif. - NASA's long-lived Mars Odyssey spacecraft has completed an eight-month adjustment of its orbit, positioning itself to look down at the day side of the planet in mid-afternoon instead of late afternoon.

This change gains sensitivity for infrared mapping of Martian minerals by the orbiter's Thermal Emission Imaging System camera. Orbit design for Odyssey's first seven years of observing Mars used a compromise between what worked best for the infrared mapping and for another onboard instrument.

"The orbiter is now overhead at about 3:45 in the afternoon instead of 5 p.m., so the ground is warmer and there is more thermal energy for the camera's infrared sensors to detect," said Jeffrey Plaut of NASA's Jet Propulsion Laboratory, Pasadena, Calif., project scientist for Mars Odyssey."

"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: Progress on Antenna Actuator - sols 2029-2034, Sept. 17-22, 2009:

"Spirit is recovering from the high-gain antenna (HGA) anomaly that occurred on Sol 2027 (Sept. 15, 2009). The HGA problem is suspected to be an apparent intermittent behavior in the dynamic brake relay for the HGA actuators, a problem that has been seen and mitigated before in other rover actuators. Diagnostics were run on the HGA and each actuator moved freely in both directions without problems with the dynamic brake behaving normally.

The challenge for the rover team has been trying to uplink HGA recovery sequences over the low-gain antenna (LGA). Data rates over the LGA are so low that there is often insufficient time in the uplink window to get up all the necessary commands. Because of that, the project is using forward link UHF relay commanding through Mars Odyssey. The forward link has the additional complication that there is additional latency in getting the commands to the rover, so the pace of recovery is impacted. Return to normal HGA usage for Spirit is anticipated by next week. Spirit is otherwise in good health.

As of Sol 2033 (Sept. 21, 2009), Spirit's solar-array energy production was 418 watt-hours with an atmospheric opacity (tau) of 0.972 and a dust factor of 0.626. Total odometry remains at 7,729.93 meters (4.80 miles)."

OPPORTUNITY UPDATE: Milestone 11 - sols 2009-2014, Sept. 18-23, 2009:

"Opportunity has driven four out of the last six sols, making way to Endeavour crater.

On sols 2009, 2011, 2013 and 2014 (Sept. 18, 20, 22 and 23), the rover drove 55 meters (180 feet), 71 meters (233 feet), 70 meters (230 feet) and 59 meters (194 feet), respectively, passing 11 miles of total odometry. Each drive was backwards heading to the west to avoid a large region of potentially risky dune ripples. Eventually, the rover will turn south, then east, to head to Endeavour.

Motor currents in the right-front wheel remain well behaved.

As of Sol 2014 (Sept. 23, 2009), Opportunity's solar-array energy production is 477 watt-hours. Atmospheric opacity (tau) is 0.681, and the dust factor on the solar array is 0.603. Total odometry is 17,717.33 meters (11.01 miles)."

Landing sites

"PASADENA, Calif. -- NASA's Mars Reconnaissance Orbiter has revealed frozen water hiding just below the surface of mid-latitude Mars. The spacecraft's observations were obtained from orbit after meteorites excavated fresh craters on the Red Planet.

Scientists controlling instruments on the orbiter found bright ice exposed at five Martian sites with new craters that range in depth from approximately half a meter to 2.5 meters (1.5 feet to 8 feet). The craters did not exist in earlier images of the same sites. Some of the craters show a thin layer of bright ice atop darker underlying material. The bright patches darkened in the weeks following initial observations, as the freshly exposed ice vaporized into the thin Martian atmosphere. One of the new craters had a bright patch of material large enough for one of the orbiter's instruments to confirm it is water-ice."

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