"The earliest stages of our Pluto encounter have begun, and New Horizons remains healthy and on course.

Already, the SWAP, PEPSSI and SDC instruments are taking daily science data - measuring the charged particle and dust environment of the space near Pluto's orbit. Next week, on Jan. 25, the sensitive LORRI long focal length camera aboard New Horizons will begin imaging the Pluto system for navigation purposes. This will yield dozens of images that our navigation teams will analyze for positional information about Pluto and Charon against star fields, allowing us to home in more accurately than by radio navigation from Earth alone."

On Video: How Do We Get to Pluto? Practice, Practice, Practice

"MESSENGER mission controllers at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., successfully conducted a maneuver today designed to raise the spacecraft's minimum altitude sufficiently to extend orbital operations and delay the probe's inevitable impact onto Mercury's surface until early next spring.

The immediately previous maneuver, completed on October 24, 2014, raised MESSENGER to an altitude at closest approach from 25.4 kilometers (15.8 miles) to 184.4 kilometers (114.6 miles) above the planet's surface. Because of progressive changes to the orbit over time, the spacecraft's minimum altitude continued to decrease.

At the time of this most recent maneuver, MESSENGER was in an orbit with a closest approach of 25.7 kilometers (16.0 miles) above the surface of Mercury. With a velocity change of 9.67 meters per second (21.62 miles per hour), the spacecraft's four largest monopropellant thrusters (with a small contribution from four of the 12 smallest monopropellant thrusters) nudged the spacecraft to an orbit with a closest approach altitude of 105.1 km (65.3 miles)."

"David F. Mitchell, MAVEN Project Manager at NASA's Goddard Space Flight Center"

"MAVEN is now fully into its Science Phase at Mars and the scientists have been releasing exciting results, not the least of which were recent findings from the Comet Siding Spring encounter. The Imaging Ultraviolet Spectrometer was able to observe intense emissions from magnesium and iron ions in the atmosphere in the aftermath of the comet encounter. The Neutral Gas and Ion Mass Spectrometer directly sampled and determined the composition of comet dust in Mars' atmosphere, something that has never been done before. Our Solar Energetic Particle instrument observed significant solar activity both in the form of flares and coronal mass ejections from the Sun to Mars. We also generated a map of Mars' ozone layer in the lower atmosphere. Finally, we've been able to provide a view of the escaping atmosphere of Mars showing the loss of atomic oxygen, atomic carbon, and atomic hydrogen. Great science with much more to come!"

Sol 884: Sample Transfer to CheMin

"By Lauren Edgar"

SPIRIT UPDATE: Spirit Remains Silent at Troy - sols 2621-2627, May 18-24, 2011:

"More than 1,300 commands were radiated to Spirit as part of the recovery effort in an attempt to elicit a response from the rover. No communication has been received from Spirit since Sol 2210 (March 22, 2010). The project concluded the Spirit recovery efforts on May 25, 2011. The remaining, pre-sequenced ultra-high frequency (UHF) relay passes scheduled for Spirit on board the Odyssey orbiter will complete on June 8, 2011.

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

OPPURTUNITY UPDATE: Several Drives This Week Put Opportunity Near Marathon Distance - sols 3909-3914, January 22, 2015-January 27, 2015: :

"Opportunity is on the west rim of Endeavour Crater heading towards "Marathon Valley," a putative location for abundant clay minerals now about 984 feet (300 meters) away.

The project is operating the rover without using the Flash storage system to avoid reset problems and is using instead random access memory (RAM) for temporary storage of telemetry. The project is preparing to mask off the troubled sector of Flash and resume using the remainder of the Flash file system in normal operations.

Opportunity drove on Sols 3909, 3911 and 3914 (Jan. 22, Jan. 24 and Jan. 27, 2015), totaling almost 279 feet (85 meters). On the evening of Sol 3912 (Jan. 25, 2015), an atmospheric argon measurement was collected with the Alpha Particle X-ray Spectrometer. Targeted color imagery is being collected as the rover makes progress towards the "Spirit of St. Louis" crater and Marathon Valley.

As of Sol 3914 (Jan. 27, 2015), the estimated solar array energy production was 534 watt-hours with an atmospheric opacity (Tau) of 0.891 and an inferred solar array dust factor of 0.636.

Total odometry is 26.02 miles (41.88 kilometers)."

"NASA is developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s - goals outlined in the bipartisan NASA Authorization Act of 2010 and in the U.S. National Space Policy, also issued in 2010.

Mars is a rich destination for scientific discovery and robotic and human exploration as we expand our presence into the solar system. Its formation and evolution are comparable to Earth, helping us learn more about our own planet's history and future. Mars had conditionssuitable for life in its past. Future exploration could uncover evidence of life, answering one of the fundamental mysteries of the cosmos: Does life exist beyond Earth?

While robotic explorers have studied Mars for more than 40 years, NASA's path for the human exploration of Mars begins in low-Earth orbit aboard the International Space Station. Astronauts on the orbiting laboratory are helping us prove many of the technologies and communications systems needed for human missions to deep space, including Mars. The space station also advances our understanding of how the body changes in space and how to protect astronaut health.

Our next step is deep space, where NASA will send a robotic mission to capture and redirect an asteroid to orbit the moon. Astronauts aboard the Orion spacecraft will explore the asteroid in the 2020s, returning to Earth with samples. This experience in human spaceflight beyond low-Earth orbit will help NASA test new systems and capabilities, such as Solar Electric Propulsion, which we'll need to send cargo as part of human missions to Mars. Beginning in FY 2018, NASA's powerful Space Launch System rocket will enable these "proving ground" missions to test new capabilities. Human missions to Mars will rely on Orion and an evolved version of SLS that will be the most powerful launch vehicle ever flown."