(From west to east)

• Flora is at opposition on the 10th in the constellation of Aquarius.
• Laetitia is at opposition on the 14th in the constellation of Pisces.
• Hebe is at opposition on the 21st in the constellation of Cetus.
• Iris is in the constellation of Gemini.

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

"Wednesday, August 18 (DOY 230) Today marked the 11th anniversary of Cassini's Earth flyby.

Friday, August 20 (DOY 232) Spacecraft Operations (SCO) successfully completed real time commanding to load Command & Data Subsystem (CDS) flight software (FSW) V10.0 patches. This is the last planned software update for CDS FSW for the remainder of the Cassini Mission. The command loss timer will be set back to 110 hours on Sunday.

SCO completed the first long reaction wheel rest period during the CDS FSW uplink and checkout period. The objective for these wheel rest periods is to allow for a redistribution of lubricants within the bearing assemblies. Bearing consultants have recommended this approach to mitigate against increased friction in the bearings, but at this point there is still insufficient data to judge the effectiveness of this plan. Attitude control was switched from reaction wheels to thrusters on Aug. 18, and switched back to wheels today.

Monday, August 23 (DOY 235) The Science Forum for S66 was held today. Topics included an overview of science planned for this sequence followed by highlights, unique activities, and highest priority observations as described by the Target Working Team (TWT) and Orbiter Science Team (OST) leads, with comments from the Investigation Scientists and other instrument team representatives.

Tuesday, August 24 (DOY 236) This week the Radio Science team performed an operational readiness test with the DSN in preparation for the occultation observation on Sept. 2. The Magnetospheric and Plasma Science instruments performed an 11.5 hour survey. The Composite Infrared Spectrometer performed an 8 hour spectroscopic observation of the infrared star CW Leonis. The Cosmic Dust Analyzer continued its interstellar dust campaign."

Cassini Imaging Team

"In early 2007 New Horizons flew through the Jupiter system, getting a speed-boost from the giant planet's gravity while snapping stunning, close-up images of Jupiter and its largest moons. Fast forward to 2010 and New Horizons has given us another glimpse of old friend Jupiter, this time from a vantage point more than 16 times the distance between Earth and the Sun, and almost 1000 times as far away as when New Horizons reconnoitered Jupiter. While the planet is too far for the camera to pick up the swirling clouds and brewing, Earth-sized storms it saw just three years ago, "the picture is a dramatic reminder of just how far New Horizons, moving about a million miles a day, has traveled," says mission Principal Investigator Alan Stern, of the Southwest Research Institute."

LORRI Looks Back

New Horizons gallery

"Engineers are studying the reaction wheels on NASA's Dawn spacecraft after automatic sensors detected excess friction building up in one of them and powered it off early on the morning of June 17, 2010. Reaction wheels spin to help a spacecraft maintain attitude control, and Dawn, which is exploring the asteroid belt, uses three wheels in normal operations.

The three other reaction wheels are functioning normally. Mission managers said plans for Dawn to visit the asteroid Vesta in 2011 and 2012 and dwarf planet Ceres in 2015 will not be not affected."

"PASADENA, Calif. - A camera aboard NASA's Mars Odyssey spacecraft has helped develop the most accurate global Martian map ever. Researchers and the public can access the map via several websites and explore and survey the entire surface of the Red Planet. The map was constructed using nearly 21,000 images from the Thermal Emission Imaging System, or THEMIS, a multi-band infrared camera on Odyssey. Researchers at Arizona State University's Mars Space Flight Facility in Tempe, in collaboration with NASA's Jet Propulsion Laboratory in Pasadena, Calif., have been compiling the map since THEMIS observations began eight years ago. The pictures have been smoothed, matched, blended and cartographically controlled to make a giant mosaic. Users can pan around images and zoom into them. At full zoom, the smallest surface details are 100 meters (330 feet) wide. While portions of Mars have been mapped at higher resolution, this map provides the most accurate view so far of the entire planet. The new map is available at: http://www.mars.asu.edu/maps/?layer=thm_dayir_100m_v11."

"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: Spirit Remains Silent at 'Troy' - sols 2356-2361, August 19-24, 2010:

"Spirit remains silent at her location on the west side of Home Plate. No communication has been received from the rover since Sol 2210 (March 22, 2010).

It is likely that Spirit has experienced a low-power fault and has turned off all sub-systems, including communication and gone into a deep sleep, trying to recharge her batteries. There is the additional risk that the rover may trip a mission clock fault. To respond to either case, the project is both listening for Spirit with the Deep Space Network and Mars Odyssey orbiter for autonomous recovery communication from the low-power fault case, and conducting a "Sweep & Beep" strategy to stimulate the rover in the case of a mission clock fault.

Although power levels are estimated to be improving with the advancing springtime in the southern hemisphere of Mars, atmospheric conditions historically deteriorate (higher atmospheric opacity) at this time. So, a response from Spirit is still not expected for some time.

Total odometry is unchanged at 7,730.50 meters (4.80 miles)."

OPPORTUNITY UPDATE: Opportunity Stops to Check Out Rocks - sols 2336-2341, August 19-25, 2010:

"Opportunity has paused in her trek toward Endeavour crater to examine an exposed outcrop of rock that is of interest to the science team.

On Sol 2336 (Aug. 19, 2010), the rover performed a 7-meter (23-foot) backward turn with a forward bump to approach the outcrop contact. On the next sol, Opportunity performed a short turn to place surface targets within reach of the robotic arm (Instrument Deployment Device, IDD). On Sol 2339 (Aug. 23, 2010), Opportunity conducted a relay test pass with Mars Express as part of a regular checkout of the Mars Express relay. On the next sol, the rover used the robotic arm to collect a microscopic imager (MI) mosaic of a surface target, called "Clarin Beach," which was followed by a placement of the alpha particle X-ray spectrometer (APXS) on the same target for integration. On Sol 2341 (Aug. 25, 2010), Opportunity continued the investigation of this outcrop contact, collecting another set of microscopic imager mosaics of new targets and then a placement of the APXS on a target called "Duero Beach."

As of Sol 2340 (Aug. 24, 2010), solar array energy production was 562 watt-hours with atmospheric opacity (Tau) of 0.334 and the solar array dust factor of 0.7285.

Total odometry as is 22,647.85 meters (22.65 kilometers, or 14.07 miles)."

Landing sites