(From west to east)

• Vesta is in the constellation of Taurus.
• Pallas is in the constellation of Orion.
• Euterpe is in the constellation of Cancer.
• Amphitrite is at opposition on the 21st in the constellation of Virgo.
• Irene is in the constellation of Virgo.
• Information about the Minor Planets can be found at the Minor Planet Observer website.

"Todd J. Barber, Cassini lead propulsion engineer - February may be a short month, but it was long on Cassini science observations at Saturn, even during the first week!

For starters, just as Punxsy Phil was emerging from his hollow stump in western Pennsylvania on Groundhog Day, Cassini was observing light and shadows as well on the intriguing moon Rhea during a non-targeted flyby. I'm sure the entire flight team is excited for our close Rhea encounter next year, particularly since this icy satellite of Saturn humbled us with the perplexing discovery of a potential ring system, the first ever seen around a moon. Until next year, though, these more distant encounters will have to suffice, whetting our voracious and bottomless scientific appetites. Also, unlike Punxsy Phil's checkered history in prognosticating six more weeks of winter, Cassini can confidently state that seasons are changing on Saturn. The north polar region will soon see the sun for the first time in nearly fifteen years, and another harbinger of seasonal change - ring spokes - should start becoming more prevalent as well. Spokes in Saturn's rings were one of the most captivating discoveries from Voyager, so we are only too happy to continue observing these beautiful, transient features with Cassini."

Cassini Imaging Team

On the anniversary of New Horizons' launch from Cape Canaveral Air Force Station, Fla., on January 19, 2006, mission team members reflect on liftoff, a busy first three years of flight and the ongoing voyage to Pluto and beyond.

Countdown to Liftoff

"To Ralph McNutt, of the Johns Hopkins Applied Physics Laboratory (APL), launch wasn't just a beginning - it was the culmination of a hard-fought, nearly two-decade-long battle in the scientific community to secure a mission to the ninth planet.

"When the announcer hit 'zero' and the Atlas V rocket began plowing its way through the wispy skin of this pale blue dot we call home, it was a special moment," says McNutt, principal investigator of the New Horizons Pluto Energetic Particle Spectrometer Science Investigation, or PEPSSI. "We really were on the way, and no one could stop us from taking that path to new lands."

Science team co-investigator Richard Binzel of the Massachusetts Institute of Technology remembers the run-up to launch, a four-year concert of spacecraft design, build and testing, and mission planning that had to reach its crescendo by January 2006, in time to meet a month-long launch period and take advantage of an opportunity to use Jupiter's gravity as a slingshot toward deeper space.

"The transition from launch to flight is truly phenomenal," Binzel says. "Before launch, the clock looms so large. Everything has to be ready at the launch window, or else! In cruise phase the pace of hard work continues, but now the responsibility feels different. We know New Horizons will reach Pluto!"

New Horizons gallery."

Mission Status Report: NASA's Dawn Mission

"With Mars disappearing in its metaphorical rearview mirror, NASA's Dawn spacecraft's next stop is the asteroid belt and the giant asteroid Vesta. Dawn got as close as 549 kilometers (341 miles) to the Red Planet during its Tuesday, Feb. 17, flyby.

Dawn's navigators placed the spacecraft on a close approach trajectory with Mars so the planet's gravitational influence would provide a kick to the spacecraft's velocity. If Dawn had to perform these orbital adjustments on its own, with no Mars gravitational deflection, the spacecraft would have had to fire up its engines and change velocity by more than 9,330 kilometers per hour (5,800 miles per hour).

The achieved goal of the flyby was to obtain this orbital pick-me-up, making possible its voyage to asteroid Vesta and, later, the dwarf planet Ceres. But Dawn's science teams used this massive target of opportunity to also perform calibrations of some of the scientific instruments. Calibration images were taken by Dawn's framing camera, and the Gamma Ray and Neutron Detector also observed Mars for calibration. These data will be compared to similar observations taken by spacecraft orbiting Mars."

"MESSENGER reaches its orbital perihelion today and passes within 0.31 astronomical units (AU) of the Sun (one AU is nearly 150 million kilometers or 93 million miles). The mission's imaging team is taking advantage of the probe's proximity to the fiery sphere to continue their search for vulcanoids - small, rocky asteroids that have been postulated to circle the Sun in stable orbits inside the orbit of Mercury.

Vulcanoids are named after Vulcan, a planet once proposed to explain unusual motions in Mercury's orbit. Scientists have long suspected that these small, faint "space rocks" exist. There is a gravitationally stable region between the orbit of Mercury and the Sun, which means that any objects that originally formed there could have remained for billions of years and might still be there today. All other such regions in the solar system are occupied by some type of debris (e.g., Trojan asteroids at stable points along the orbits of Jupiter and Neptune and Kuiper Belt objects near and beyond the orbit of Pluto).

The so-called vulcanoid region between the orbit of Mercury and the Sun is the main gravitationally stable region that is not known to be occupied. The region is, however, the most difficult to observe. Any vulcanoids would be difficult to detect from Earth because of the strong glare of the Sun. Previous vulcanoid searches have revealed no bodies larger than 60 kilometers in diameter. But MESSENGER's travels in near-Mercury space enable a search for vulcanoids from a vantage never before attempted, says MESSENGER Science Team Member Clark Chapman, who is spearheading the teamÕs search along with his associate, William Merline."

"An international team of scientists who analyzed data from the Gamma Ray Spectrometer onboard NASA's Mars Odyssey reports new evidence for the controversial idea that oceans once covered about a third of ancient Mars.

"We compared Gamma Ray Spectrometer data on potassium, thorium and iron above and below a shoreline believed to mark an ancient ocean that covered a third of Mars' surface, and an inner shoreline believed to mark a younger, smaller ocean," said University of Arizona planetary geologist James M. Dohm, who led the international investigation.

"Our investigation posed the question, Might we see a greater concentration of these elements within the ancient shorelines because water and rock containing the elements moved from the highlands to the lowlands, where they eventually ponded as large water bodies?" Dohm said."

"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: Another Cleaning - sol 1817-1823, February 11-17, 2009:

Spirit has been continuing attempts to reach an on-ramp for ascending onto "Home Plate." The terrain continues to be difficult for driving with five wheels. Because of limited progress on previous sols, on Sol 1818 (February 12, 2009), Spirit attempted a series of sharp backward arcs. Spirit executed 60-centimeter (2-foot) arcs 29 times, but, due to wheel slippage, the rover made only 17 centimeters (7 inches) of progress.

On Sol 1820 (February 14, 2009), the plan was to drive forward, away from Home Plate, and turn. The rover was successful in turning about 45 degrees, sufficient to get the wheels out of the soft terrain where they had been digging in. Spirit will next attempt the approach to Home Plate while avoiding some of the soft terrain that complicated previous approaches.

The team continues to track the performance of the rover's accelerometers.

Another small dust-cleaning event on Sol 1820 (February 14, 2009) -- the second one this month -- improved solar-array performance by an additional 10 percent.

As of Sol 1823 (February 17, 2009) Spirit's solar-array energy production improved to 275 watt-hours. Atmospheric opacity (tau) increased slightly to 0.530. The dust factor is 0.306, meaning that 30.2 percent of the sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health.

Spirit's total odometry as of Sol 1822 (February 16, 2009) is 7,572.23 meters (4.71 miles)

OPPORTUNITY UPDATE: Checking the Right-Front Wheel - sol 1797-1802, February 12-17, 2009:

Opportunity is continuing with a series of long drives. The drive on Sol 1797 (February 12, 2009) achieved 111 meters (364 feet). During the drive the right-front wheel exhibited higher-than-usual motor currents. Since April 2005, Opportunity's right-front wheel has had a jammed steering actuator, with the wheel turned inwards about 7 degrees from straight ahead, so it works harder on some drives. On Sol 1800 (February 15, 2009), the rover conducted a series of mobility diagnostic drives to study the right-front wheel. The rover turned around and drove backward about 10 meters (31 feet), turned around again and drove forward about 11 meters (36 feet), and then performed an arc of about 4 meters (13 feet). The wheel currents were monitored.

The plan for the near term is to drive backward to see if that improves performance of the right-front wheel, although backward driving will limit the distance traveled each sol.

As of Sol 1802 (February 17, 2009), Opportunity's solar-array energy production is 567 watt-hours. Atmospheric opacity (tau) has moderated to 0.540. The dust factor on the solar array is 0.589, meaning that 58.9 percent of the sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health.

Opportunity's total odometry as of Sol 1801 (February 16, 2009) is 14,621.57 meters (9.09 miles)."

Landing sites

"Images from NASA's Mars Reconnaissance Orbiter show a type of rock fracturing that here on Earth is caused by rapid cooling of lava.

Unique fractures in lavas on ancient Mars suggest water occasionally flooded portions of the planet's surface.

The fractures, known as "columnar joints", are the first that have been observed on a planet other than Earth. "Columnar joints form as cooling lava contracts," explains Moses Milazzo, a geophysicist with the U.S. Geological Survey in Flagstaff. The characteristics of the column-like fractures can help scientists understand the role of water in geologic processes on Mars. Milazzo, working with the NASA Mars Reconnaissance Orbiter HiRISE camera team, recently published their discovery in the journal Geology.

The columns, a meter in diameter and about 30 meters high, were identified in the tilted inner walls of an impact crater. "The HiRISE instrument just barely has the resolution to pick out the columns if they're facing the camera with the perfect orientation," said Milazzo. When the impact crater formed, the rocks were tilted backward, toward the sky. This tilting of the columns toward the sky is what allowed the identification."

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

"The team that developed and operated NASA's Phoenix Mars Lander mission will receive the 2009 John L. "Jack" Swigert Award for Space Exploration from the Space Foundation.

During five months of operations at a Martian arctic site after landing on May 25, 2008, the Phoenix spacecraft confirmed the presence of frozen water just below the surface, identified potential nutrients and other substances in the soil, and observed snow in the atmosphere.

The Space Foundation, based in Colorado Springs, Colo., announced Feb. 19 that it will present the award to the Phoenix team on March 30, during the foundation's 25th National Space Symposium, in Colorado Springs."
Full image and caption