(From west to east)

• Vesta is in the constellation of Virgo.
• Pallas is stationary on the 3rd in the constellation of Boötes.
• Eunomia is in the constellation of Sagittarius.
• Amphitrite is at opposition on the 3rd in the constellation of Sagittarius.
• Flora is in the constellation of CetusCetus.
• Hebe is in the constellation of CetusCetus.

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

"PASADENA, Calif. -- Two new papers based on data from NASA's Cassini spacecraft scrutinize the complex chemical activity on the surface of Saturn's moon Titan. While non-biological chemistry offers one possible explanation, some scientists believe these chemical signatures bolster the argument for a primitive, exotic form of life or precursor to life on Titan's surface. According to one theory put forth by astrobiologists, the signatures fulfill two important conditions necessary for a hypothesized 'methane-based life.'

One key finding comes from a paper online now in the journal Icarus that shows hydrogen molecules flowing down through Titan's atmosphere and disappearing at the surface. Another paper online now in the Journal of Geophysical Research maps hydrocarbons on the Titan surface and finds a lack of acetylene."

Cassini Imaging Team

"New Horizons' fourth annual checkout is nearing its mid-point, and continues with a workout for the spacecraft systems, cameras and other instruments that will deliver the first data from Pluto and its moons. Preparations for a small but necessary course-correction maneuver are also on track.

Since "ACO-4" began on May 25, mission operators have uploaded new software for New Horizons' on-board autonomy system, and checked out most of the spacecraft's backup systems, including guidance and control, communications, command and data handling, thermal control, power and propulsion. All of these backup systems have performed well."

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."

"Two members of the MESSENGER team have been honored by their peers. Carl Jack Ercol, the man largely responsible for ensuring that MESSENGER can withstand solar radiation up to 11 times greater than at Earth as it orbits the planet closest to the Sun, has received the 2008 SAE Arch T. Colwell Merit Award. Independently, MESSENGER Co-Investigator James W. Head, III, was awarded the Runcorn-Florensky Medal by the European Geosciences Union (EGU) at their General Assembly earlier this month.

SAE International, a global association of more than 128,000 engineers and related technical experts in the aerospace, automotive, and commercial-vehicle industries, annually recognizes authors of papers of outstanding technical or professional merit presented at a meeting of the society during the calendar year. Papers are judged primarily for their value as new contributions to existing knowledge of mobility engineering."

"California middle school students using the camera on NASA's Mars Odyssey orbiter have found lava tubes with one pit that appears to be a skylight to a cave.

The students in science teacher Dennis Mitchell's class at Evergreen Middle School in Cottonwood, Calif., were examining Martian lava tubes as their project in the Mars Student Imaging Program offered by NASA and Arizona State University. Students in this program develop a geological question, then target a Mars-orbiting camera to take an image that helps answer the question."

"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 Standing by At Troy - sols 2295-2300, June 17-22, 2010:

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

As stated previously, 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. While sleeping, the rover will use the available solar array energy to recharge her batteries. When the batteries recover to a sufficient state of charge, Spirit will wake up and begin to communicate.

There is the additional risk that the rover may trip a mission clock fault. If that happens, the rover would remain asleep until the batteries have recharged sufficiently and there is enough sunlight on the solar arrays to wake the rover. With the southern winter solstice back on May 13, 2010, solar energy levels and temperatures are expected to be improving.

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

OPPORTUNITY UPDATE: Opportunity Completes Three Drives This Week - sols 2273-2279, June 16-22, 2010:

"Opportunity has been making good progress toward Endeavour crater with three drives in the past week.

On Sol 2274 (June 17, 2010), the rover completed over 60 meters (197 feet) driving due east. On Sol 2276 (June 19, 2010), the rover made a small J-turn to avoid a ripple and then headed 72 meters (236 feet) east. With this drive, Opportunity has passed the distance for a half-marathon (21,097.5 meters, or 13 miles).

The rover drove again on Sol 2279 (June 22, 2010), covering over 70 meters (230 feet) to the east/southeast.

As of Sol 2279 (June 22, 2010), solar array energy production has improved to 320 watt-hours, atmospheric opacity (Tau) was 0.257 and the solar array dust factor is 0.5585.

Total odometry is 21,209.69 meters (21.21 kilometers, or 13.18 miles)."

Landing sites