(From west to east)

• Vesta is at opposition on the 29th in the constellation of Cetus.
• Metis is in the constellation of Cetus.
• Information about the Minor Planets can be found at the Minor Planet Observer website.

"Saturn's high north is a seething cauldron of activity filled with roiling cloud bands and swirling vortices. A corner of the North Polar Hexagon is seen at upper left. This view looks toward a region located about 70 degrees north of the planet's equator, in a place that receives continually increasing amounts of sunlight as Saturn's seasons change.

The image was taken with the Cassini spacecraft wide-angle camera on Aug. 25, 2008 using a spectral filter sensitive to wavelengths of infrared light centered at 752 nanometers. The view was obtained at a distance of approximately 541,000 kilometers (336,000 miles) from Saturn. Image scale is 29 kilometers (18 miles) per pixel."

Cassini Imaging Team

"The New Horizons team Ð including hundreds of technicians, engineers, scientists, managers, educators and communications specialists from more than 20 institutions across the country Ð has been given the NASA Group Achievement Award for creating and launching the first mission to Pluto and the Kuiper Belt.

NASA Planetary Science Division Director James Green made the presentation Sept. 11 at the Johns Hopkins Applied Physics Lab in Laurel, Md., where New Horizons was designed and built, and is now operated. APL also manages the mission for NASAÕs Science Mission Directorate; John Sommerer, acting head of the LabÕs Space Department, accepted the award on behalf of the many APL staff members who developed the mission and spacecraft."

New Horizons gallery."

"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."

"One week from today, the MESSENGER spacecraft will fly by Mercury for the second time this year. As part of the final preparations for this encounter, the Mercury Laser Altimeter (MLA) has been powered on after having been off since shortly after the first flyby at the beginning of the year. The entire MESSENGER science payload is now powered and configured to collect data during next weekÕs encounter.

ÒRight after the January flyby, the MLA completed passive observations of Mercury, without the laser firing, as a calibration,Ó explained MLA Instrument Scientist Olivier Barnouin-Jha of the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. ÒAt that point it was switched off, and it has remained off since that time.Ó

During MESSENGERÕs first Mercury encounter, the MLA provided the first direct measurements of the topography of Mercury from spacecraft. The results provide evidence for a complex geologic history and indicate that MercuryÕs craters are shallower than those on the Moon at a given crater diameter, as expected because of the higher surface gravity.

ÒUnlike the topographic data obtained during the first flyby, which were of terrain for which we have no space-based imaging, some of the area to which MLA will range during this second encounter was imaged by the Mercury Dual Imaging System (MDIS) during the first Mercury flyby,Ó Barnouin-Jha said. Moreover, terrain sampled by MLA during the first flyby will in turn be imaged by MDIS during this visit.

ÒSo this second flyby will allow the first inter-comparison between the topographic observations and high-resolution spacecraft images,Ó he added."

"PASADENA, Calif. - NASA's Mars Odyssey orbiter has found evidence of salt deposits. These deposits point to places where water once was abundant and where evidence might exist of possible Martian life from the Red Planet's past.

A team led by Mikki Osterloo of the University of Hawaii, Honolulu, found approximately 200 places on southern Mars that show spectral characteristics consistent with chloride minerals. Chloride is part of many types of salt, such as sodium chloride or table salt. The sites range from about a square kilometer (0.4 square mile) to 25 times that size."

"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/

September 22-26, 2008

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

• Yardangs (Released 22 September 2008)
  
• Lunae Planum (Released 23 September 2008)
  
• Bright Dunes (Released 24 September 2008)
  
• Crater Ejecta (Released 25 September 2008)
  
• Marte Vallis (Released 26 September 2008)
  
• 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: Warming Up on Mars - sol 1669-1677, September 12-20, 2008

"With Martian winter on the wane, Spirit is using significantly less energy to stay warm. During the winter solstice, Spirit needed 90 watt-hours to run the heater. Now, the rover uses between 30 and 40 watt-hours. The reduced demand for power, more than the slow increase in solar-array input, has freed up energy for other things. In particular, Spirit has added more images to the 360-degree view of its winter surroundings, known as the "Bonestell panorama." The top tier, one of three tiers needed for the final image mosaic, is almost complete.

Plans called for Spirit to use the miniature thermal emission spectrometer for the first time in several months. The last time the rover used the instrument was on Martian day, or sol, 1558 (May 21, 2008). On sol 1675 (Sept. 18, 2008), Spirit's schedule of activities included calibrating the spectometer and using it to observe the sky and ground. Normally, scientists use the observations to measure temperatures at different heights and create a temperature profile of the ground and atmosphere. In this case, the purpose of the measurements is to verify that the spectrometer is still working after a long, cold period of disuse. The measurements will also enable scientists to estimate the amount of dust on the optics. They may or may not provide a useful temperature profile.

Spirit is healthy and all subsystems are performing as expected as of the most recent report from NASA's Odyssey orbiter on sol 1674 (Sept. 17, 2008). Solar-array energy has inched upward to 255 watt-hours (100 watt-hours is the amount of energy needed to light a 100-watt bulb for one hour). Skies are clearer than last week, with tau, a measure of the amount of sunlight blocked by atmospheric dust, dropping to 0.141."

Opportunity Status: Slipping Like a Dune Buggy - sol 1648-1654, September 12-18, 2008

"During the past week, Opportunity has been trying to reach a patch of dust between two crests of the ridge surrounding "Victoria Crater." The rover approached the ridge from the west, driving on flat ground, on Martian days, or sols, 1648 and 1650 (Sept. 12 and Sept. 14, 2008). Then, after reaching a staging position, Opportunity began to climb the ridge. That's when the rover's wheels began slipping excessively on the sandy slope.

Rover drivers decided to give Opportunity another chance to make it up the slope by loosening the slip constraints. This allowed Opportunity to keep trying to climb the slope with a higher rate of wheel slippage. If the attempt to do this as planned on sol 1654 (Sept. 18, 2008) is not successful, rover drivers may try a different approach or abandon the effort.

After the dust patch campaign, plans call for Opportunity to drive south toward a 20-kilometer-wide (12-mile-wide) crater 12 kilometers (7.5 miles) away.

Opportunity is healthy, and all subsystems are performing as expected. Based on the latest data from sol 1653 (Sept. 17, 2008), the rover has 582 watt-hours of solar power available each day. (One hundred watt-hours is the amount of energy needed to light a 100-watt bulb for one hour.)"

Landing sites