WASHINGTON — NASA’s Phoenix Mars Lander has ceased communications after operating for more than five months. As anticipated, seasonal decline in sunshine at the robot’s arctic landing site is not providing enough sunlight for the solar arrays to collect the power necessary to charge batteries that operate the lander’s instruments.

Mission engineers last received a signal from the lander on Nov. 2. Phoenix, in addition to shorter daylight, has encountered a dustier sky, more clouds and colder temperatures as the northern Mars summer approaches autumn. The mission exceeded its planned operational life of three months to conduct and return science data.

The project team will be listening carefully during the next few weeks to hear if Phoenix revives and phones home. However, engineers now believe that is unlikely because of the worsening weather conditions on Mars. While the spacecraft’s work has ended, the analysis of data from the instruments is in its earliest stages.

“Phoenix has given us some surprises, and I’m confident we will be pulling more gems from this trove of data for years to come,” said Phoenix Principal Investigator Peter Smith of the University of Arizona in Tucson.

Launched Aug. 4, 2007, Phoenix landed May 25, 2008, farther north than any previous spacecraft to land on the Martian surface. The lander dug, scooped, baked, sniffed and tasted the Red Planet’s soil. Among early results, it verified the presence of water-ice in the Martian subsurface, which NASA’s Mars Odyssey orbiter first detected remotely in 2002. Phoenix’s cameras also returned more than 25,000 pictures from sweeping vistas to near the atomic level using the first atomic force microscope ever used outside Earth.

“Phoenix not only met the tremendous challenge of landing safely, it accomplished scientific investigations on 149 of its 152 Martian days as a result of dedicated work by a talented team,” said Phoenix Project Manager Barry Goldstein at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

Phoenix’s preliminary science accomplishments advance the goal of studying whether the Martian arctic environment has ever been favorable for microbes. Additional findings include documenting a mildly alkaline soil environment unlike any found by earlier Mars missions; finding small concentrations of salts that could be nutrients for life; discovering perchlorate salt, which has implications for ice and soil properties; and finding calcium carbonate, a marker of effects of liquid water.

Phoenix findings also support the goal of learning the history of water on Mars. These findings include excavating soil above the ice table, revealing at least two distinct types of ice deposits; observing snow descending from clouds; providing a mission-long weather record, with data on temperature, pressure, humidity and wind; observations of haze, clouds, frost and whirlwinds; and coordinating with NASA’s Mars Reconnaissance Orbiter to perform simultaneous ground and orbital observations of Martian weather.

“Phoenix provided an important step to spur the hope that we can show Mars was once habitable and possibly supported life,” said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters in Washington. “Phoenix was supported by orbiting NASA spacecraft providing communications relay while producing their own fascinating science. With the upcoming launch of the Mars Science Laboratory, the Mars Program never sleeps.”

The University of Arizona leads the Phoenix mission with project management at JPL and development partnership at Lockheed Martin Corporation in Denver. International contributions came from the Canadian Space Agency; the University of Neuchatel, Switzerland; the universities of Copenhagen and Aarhus in Denmark; the Max Planck Institute in Germany; the Finnish Meteorological Institute; and Imperial College of London.

TUCSON, Ariz. — Laboratory tests aboard NASA’s Phoenix Mars Lander have identified water in a soil sample. The lander’s robotic arm delivered the sample Wednesday to an instrument that identifies vapors produced by the heating of samples.

“We have water,” said William Boynton of the University of Arizona, lead scientist for the Thermal and Evolved-Gas Analyzer, or TEGA. “We’ve seen evidence for this water ice before in observations by the Mars Odyssey orbiter and in disappearing chunks observed by Phoenix last month, but this is the first time Martian water has been touched and tasted.”

With enticing results so far and the spacecraft in good shape, NASA also announced operational funding for the mission will extend through Sept. 30. The original prime mission of three months ends in late August. The mission extension adds five weeks to the 90 days of the prime mission.

“Phoenix is healthy and the projections for solar power look good, so we want to take full advantage of having this resource in one of the most interesting locations on Mars,” said Michael Meyer, chief scientist for the Mars Exploration Program at NASA Headquarters in Washington.

The soil sample came from a trench approximately 2 inches deep. When the robotic arm first reached that depth, it hit a hard layer of frozen soil. Two attempts to deliver samples of icy soil on days when fresh material was exposed were foiled when the samples became stuck inside the scoop. Most of the material in Wednesday’s sample had been exposed to the air for two days, letting some of the water in the sample vaporize away and making the soil easier to handle.

“Mars is giving us some surprises,” said Phoenix principal investigator Peter Smith of the University of Arizona. “We’re excited because surprises are where discoveries come from. One surprise is how the soil is behaving. The ice-rich layers stick to the scoop when poised in the sun above the deck, different from what we expected from all the Mars simulation testing we’ve done. That has presented challenges for delivering samples, but we’re finding ways to work with it and we’re gathering lots of information to help us understand this soil.”

Since landing on May 25, Phoenix has been studying soil with a chemistry lab, TEGA, a microscope, a conductivity probe and cameras. Besides confirming the 2002 finding from orbit of water ice near the surface and deciphering the newly observed stickiness, the science team is trying to determine whether the water ice ever thaws enough to be available for biology and if carbon-containing chemicals and other raw materials for life are present.

The mission is examining the sky as well as the ground. A Canadian instrument is using a laser beam to study dust and clouds overhead.

“It’s a 30-watt light bulb giving us a laser show on Mars,” said Victoria Hipkin of the Canadian Space Agency.

A full-circle, color panorama of Phoenix’s surroundings also has been completed by the spacecraft.

“The details and patterns we see in the ground show an ice-dominated terrain as far as the eye can see,” said Mark Lemmon of Texas A&M University, lead scientist for Phoenix’s Surface Stereo Imager camera. “They help us plan measurements we’re making within reach of the robotic arm and interpret those measurements on a wider scale.”

The Phoenix mission is led by Smith at the University of Arizona with project management at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and development partnership at Lockheed Martin in Denver. International contributions come from the Canadian Space Agency; the University of Neuchatel, Switzerland; the universities of Copenhagen and Aarhus in Denmark; the Max Planck Institute in Germany; and the Finnish Meteorological Institute.

PASADENA, Calif. — NASA scientists have concluded that at least one of the large lakes observed on Saturn’s moon Titan contains liquid hydrocarbons, and have positively identified the presence of ethane. This makes Titan the only body in our solar system beyond Earth known to have liquid on its surface.

Scientists made the discovery using data from an instrument aboard the Cassini spacecraft. The instrument identified chemically different materials based on the way they absorb and reflect infrared light. Before Cassini, scientists thought Titan would have global oceans of methane, ethane and other light hydrocarbons. More than 40 close flybys of Titan by Cassini show no such global oceans exist, but hundreds of dark lake-like features are present. Until now, it was not known whether these features were liquid or simply dark, solid material.

“This is the first observation that really pins down that Titan has a surface lake filled with liquid,” said Bob Brown of the University of Arizona, Tucson. Brown is the team leader of Cassini’s visual and mapping instrument. The results will be published in the July 31 issue of the journal Nature.

Ethane and several other simple hydrocarbons have been identified in Titan’s atmosphere, which consists of 95 percent nitrogen, with methane making up the other 5 percent. Ethane and other hydrocarbons are products from atmospheric chemistry caused by the breakdown of methane by sunlight.

Some of the hydrocarbons react further and form fine aerosol particles. All of these things in Titan’s atmosphere make detecting and identifying materials on the surface difficult, because these particles form a ubiquitous hydrocarbon haze that hinders the view. Liquid ethane was identified using a technique that removed the interference from the atmospheric hydrocarbons.

The visual and mapping instrument observed a lake, Ontario Lacus, in Titan’s south polar region during a close Cassini flyby in December 2007. The lake is roughly 7,800 square miles in area, slightly larger than North America’s Lake Ontario.

“Detection of liquid ethane confirms a long-held idea that lakes and seas filled with methane and ethane exist on Titan,” said Larry Soderblom, a Cassini interdisciplinary scientist with the U.S. Geological Survey in Flagstaff, Ariz. “The fact we could detect the ethane spectral signatures of the lake even when it was so dimly illuminated, and at a slanted viewing path through Titan’s atmosphere, raises expectations for exciting future lake discoveries by our instrument.”

The ethane is in a liquid solution with methane, other hydrocarbons and nitrogen. At Titan’s surface temperatures, approximately 300 degrees Fahrenheit below zero, these substances can exist as both liquid and gas. Titan shows overwhelming evidence of evaporation, rain, and fluid-carved channels draining into what, in this case, is a liquid hydrocarbon lake.

Earth has a hydrological cycle based on water and Titan has a cycle based on methane. Scientists ruled out the presence of water ice, ammonia, ammonia hydrate and carbon dioxide in Ontario Lacus. The observations also suggest the lake is evaporating. It is ringed by a dark beach, where the black lake merges with the bright shoreline. Cassini also observed a shelf and beach being exposed as the lake evaporates.

“During the next few years, the vast array of lakes and seas on Titan’s north pole mapped with Cassini’s radar instrument will emerge from polar darkness into sunlight, giving the infrared instrument rich opportunities to watch for seasonal changes of Titan’s lakes,” Soderblom said.

Launched in Oct. 1997, Cassini’s 12 instruments have returned a daily stream of data from Saturn’s system. The mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency.

TUCSON, Ariz. — NASA’s Phoenix Mars Lander today made its first dig into Martian soil for science studies and is poised to deliver the scoopful to a laboratory instrument on the lander deck.

The instrument will bake and sniff the soil to assess its volatile ingredients, such as water.

Commands were received by Phoenix Friday, June 6, for the spacecraft’s Robotic Arm to dump the sample into an opened door on the instrument called the Thermal and Evolved-Gas Analyzer, or TEGA.

“It’s looks like a good sample for us,” said Peter Smith, Phoenix principal investigator at the University of Arizona, Tucson. “Over the next few days, and it may be as much as a week, the TEGA instrument will be analyzing this sample.”

Phoenix’s Robotic Arm collected the sample of clumpy, reddish material from the top 2 to 4 centimeters (0.8 to 1.6 inches) of surface material at a site informally named “Baby Bear” on the north side of the lander. In the past week, engineers had used the arm to collect two practice scoops adjacent to Baby Bear and dump those scoopfuls back onto the surface. They have prepared for years with simulations and versions of the arm on Earth.

“It’s like being on a football team and having a pre-season that lasted five years, and now we’re finally playing first game,” said Matt Robinson, of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. He is the robotic arm flight software lead for the Phoenix team.

The move was calculated to get enough material to be sure to get some delivered into the instrument without inundating the instrument with unnecessary extra soil. “We’re ecstatic that we got a quarter to a third of a scoopful,” Robinson said.

The TEGA instrument will begin analyzing the sample for water and mineral content after it has analyzed a sample of the Martian atmosphere. Water can be bound to minerals, such as clays or carbonates, and it takes more heat to drive the water off some minerals than others. This is how the instrument can identify some minerals in the soil.

“We are particularly interested in minerals that are formed or altered by the action of liquid water in the soil,” Smith said.

The Phoenix mission is led by Smith at the University of Arizona with project management at JPL and development partnership at Lockheed Martin, Denver. International contributions come from the Canadian Space Agency; the University of Neuchatel, Switzerland; the universities of Copenhagen and Aarhus, Denmark; Max Planck Institute, Germany; and the Finnish Meteorological Institute.

PASADENA, Calif. — NASA’s Phoenix spacecraft landed in the northern polar region of Mars today to begin three months of examining a site chosen for its likelihood of having frozen water within reach of the lander’s robotic arm.

Radio signals received at 4:53:44 p.m. Pacific Time (7:53:44 p.m. Eastern Time) confirmed the Phoenix Mars Lander had survived its difficult final descent and touchdown 15 minutes earlier. The signals took that long to travel from Mars to Earth at the speed of light.

Mission team members at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.; Lockheed Martin Space Systems, Denver; and the University of Arizona, Tucson, cheered confirmation of the landing and eagerly awaited further information from Phoenix later tonight.

Among those in the JPL control room was NASA Administrator Michael Griffin, who noted this was the first successful Mars landing without airbags since Viking 2 in 1976.

“For the first time in 32 years, and only the third time in history, a JPL team has carried out a soft landing on Mars,” Griffin said. “I couldn’t be happier to be here to witness this incredible achievement.”

During its 422-million-mile flight from Earth to Mars after launching on Aug. 4, 2007, Phoenix relied on electricity from solar panels during the spacecraft’s cruise stage. The cruise stage was jettisoned seven minutes before the lander, encased in a protective shell, entered the Martian atmosphere. Batteries provide electricity until the lander’s own pair of solar arrays spread open.

“We’ve passed the hardest part and we’re breathing again, but we still need to see that Phoenix has opened its solar arrays and begun generating power,” said JPL’s Barry Goldstein, the Phoenix project manager. If all goes well, engineers will learn the status of the solar arrays between 7 and 7:30 p.m. Pacific Time (10 and 10:30 p.m. Eastern Time) from a Phoenix transmission relayed via NASA’s Mars Odyssey orbiter.

The team will also be watching for the Sunday night transmission to confirm that masts for the stereo camera and the weather station have swung to their vertical positions.

“What a thrilling landing! But the team is waiting impatiently for the next set of signals that will verify a healthy spacecraft,” said Peter Smith of the University of Arizona, principal investigator for the Phoenix mission. “I can hardly contain my enthusiasm. The first landed images of the Martian polar terrain will set the stage for our mission.”

Another critical deployment will be the first use of the 7.7-foot-long robotic arm on Phoenix, which will not be attempted for at least two days. Researchers will use the arm during future weeks to get samples of soil and ice into laboratory instruments on the lander deck.

The signal confirming that Phoenix had survived touchdown was relayed via Mars Odyssey and received on Earth at the Goldstone, Calif., antenna station of NASA’s Deep Space Network.

Phoenix uses hardware from a spacecraft built for a 2001 launch that was canceled in response to the loss of a similar Mars spacecraft during a 1999 landing attempt. Researchers who proposed the Phoenix mission in 2002 saw the unused spacecraft as a resource for pursuing a new science opportunity. Earlier in 2002, Mars Odyssey discovered that plentiful water ice lies just beneath the surface throughout much of high-latitude Mars. NASA chose the Phoenix proposal over 24 other proposals to become the first endeavor in the Mars Scout program of competitively selected missions.

The Phoenix mission is led by Smith at the University of Arizona with project management at JPL and development partnership at Lockheed Martin, Denver. International contributions come from the Canadian Space Agency; the University of Neuchatel, Switzerland; the universities of Copenhagen and Aarhus, Denmark; Max Planck Institute, Germany; and the Finnish Meteorological Institute. For more about Phoenix, visit http://www.nasa.gov/phoenix

NASA’s Cassini spacecraft performed a daring flyby of Saturn’s moon Enceladus on Wed., March 12, flying about 32,000 miles per hour (15 kilometers per second) through icy water geyser-like jets. The spacecraft snatched up precious samples that might point to a water ocean or organics inside the little moon.

Scientists believe the geysers could provide evidence that liquid water is trapped under the icy crust of Enceladus. The geysers emanate from fractures running along the moon’s south pole, spewing out water vapor at approximately 800 mph (400 meters per second).

The new data provide a much more detailed look at the fractures that modify the surface and will give a significantly improved comparison between the geologic history of the moon’s north pole and south pole.

New images show that compared to much of the southern hemisphere on Enceladus–the south polar region in particular–the north polar region is much older and pitted with craters of various sizes. These craters are captured at different stages of disruption and alteration by tectonic activity, and probably from past heating from below. Many of the craters seem sliced by small parallel cracks that appear to be ubiquitous throughout the old cratered terrains on Enceladus.

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WASHINGTON - The recent flyby of Mercury by NASA’s MESSENGER spacecraft has given scientists an entirely new look at a planet once thought to have characteristics similar to those of Earth’s moon. Researchers are amazed by the wealth of images and data that show a unique world with a diversity of geological processes and a very different magnetosphere from the one discovered and sampled more than 30 years ago.

After a journey of more than 2 billion miles and three and a half years, NASA’s MErcury Surface, Space ENvironment, GEochemistry and Ranging spacecraft made its first flyby on Jan. 14. The mission is the first sent to orbit the planet closest to our sun. The spacecraft’s cameras and other sophisticated, high-technology instruments collected more than 1,200 images and made other science observations. Data included the first up-close measurements of Mercury since the Mariner 10 spacecraft’s third and final flyby on March 16, 1975.

“This flyby allowed us to see a part of the planet never before viewed by spacecraft, and our little craft has returned a gold mine of exciting data,” said Sean Solomon, MESSENGER’s principal investigator, Carnegie Institution of Washington. “From the perspectives of spacecraft performance and maneuver accuracy, this encounter was near-perfect, and we are delighted that all of the science data are now on the ground.”

Unlike the moon, the spacecraft showed that Mercury has huge cliffs with structures snaking up hundreds of miles across the planet’s face. These cliffs preserve a record of patterns of fault activity from early in the planet’s history. The spacecraft also revealed impact craters that appear very different from lunar craters.
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