June 2013

The NASA Astrobiology Program has begun the process of developing a new Astrobiology Roadmap to chart the future directions of astrobiology research. During the month of May, NASA hosted a series of on-line hangouts and discussions focusing on broad themes in astrobiology.

The NAI is pleased to announce selections for the 2013 Lewis and Clark Fund for Exploration and Field Research in Astrobiology.

The NASA Astrobiology Program Early Career Collaboration Award offers research-related travel support for graduate students and postdoctoral fellows. Applicants are encouraged to use these resources to circulate among two or more research teams, however any travel that is critical for the applicant's research will be considered.

The Astrobiology Program has selected 5 faculty members from minority serving institutions to conduct research in the labs of NASA Astrobiology Program researchers as part of the Minority Institution Research Support (MIRS) program during 2013.

Writing in the journal Nature Geoscience, astrobiologists Alberto Fairen of Cornell University and Dirk Schulze-Makuch of Washington State University say the NASA Office of Planetary Protection's "detailed and expensive" efforts to keep Earth microorganisms off Mars are making missions to search for life on the red planet "unviable."

- Overprotection may be hampering hunt for Mars life, new Scientist
- Manganese-oxidizing photosynthesis before the rise of cyanobacteria, PNAS
- The overprotection of Mars, Nature Geoscience
- Travelogue from Young Researchers in the Field, Astrobiology Magazine

For most terrestrial life on Earth, oxygen is necessary for survival. But the planet's atmosphere did not always contain this life-sustaining substance, and one of science's greatest mysteries is how and when oxygenic photosynthesis--the process responsible for producing oxygen on Earth through the splitting of water molecules--first began.

One of the most profound questions about the newly discovered class of low-density super-Earths is whether these exoplanets are predominately H2-dominated mini-Neptunes or volatile-rich worlds with gas envelopes dominated by H2O, CO2, CO, CH4, or N2.

Colonies of bacteria grown aboard the Space Shuttle Atlantis behaved in ways never before observed on Earth, according to a new NASA-funded study from Rensselaer Polytechnic Institute, Troy, New York. Recent findings provide important evidence of spaceflight's effect on the behavior of bacterial communities, and represent a key step toward understanding and mitigating the risk these bacteria may pose to astronauts during long-term space missions.

Recent calculations suggest that the inner edge of the habitable zone around the Sun could be as far out as 0.99 astronomical units (AU)- much closer to the orbit of Earth than had been thought. This reopens the question of whether future increases in atmospheric CO2 might trigger a runaway or moist greenhouse. A runaway greenhouse implies complete ocean vaporization; a moist greenhouse implies that the stratosphere becomes wet, leading to ocean loss via hydrogen escape to space.

- Luminosity of young Jupiters revisited. Massive cores make hot planets, astro-ph
- A dynamically-packed planetary system around GJ667C with three super-Earths in its habitable zone, astro-ph
- How close is Earth to a runaway greenhouse?, astro-ph
- The Formation and Dynamics of Super-Earth Planets, astro-ph
- Compositional diversity in the atmospheres of hot Neptunes, with application to GJ 436b, astro-ph

A team of astronomers, including Carnegie's Paul Butler, has combined new observations with existing data to reveal a solar system packed full of planets. The star Gliese 667C is orbited by between five and seven planets, the maximum number that could fit in stable, close orbits. A record-breaking three of these planets are super-Earths found in the so-called habitable zone around the star -- the zone where liquid water could exist. This makes them good candidates for the search for life.

Antifreeze normally helps prevent freezing, but scientists find a common antifreeze compound that might exist on Saturn's largest moon Titan can get trapped within ice-like cages.

The compositions of the 3.7-billion-year-old surface rocks on Mars -- as observed by the Spirit rover at Gusev crater -- are shown to be consistent with early mixing of oxidized surface material into the uppermost Martian mantle: such oxidation appears to have had less influence on more recent volcanic rocks, which are sampled as Martian meteorites.

The Astrobiology Program has completed the first step in creating a new Astrobiology Roadmap. The next phase in outlining the future direction for astrobiology research and technology development at NASA is set to begin today.

The autonomous, solar-powered Zoe, which became the first robot to map microbial life during a 2005 field expedition in Chile's Atacama Desert, is heading back to the world's driest desert this month on a NASA astrobiology mission led by Carnegie Mellon University and the SETI Institute. This time, Zoe is equipped with a one-meter drill to search for subsurface life.

Researchers from the University of Hawaii at Manoa NASA Astrobiology Institute (UHNAI) have discovered high concentrations of boron in a Martian meteorite. When present in its oxidized form (borate), boron may have played a key role in the formation of RNA, one of the building blocks for life. The work was published on June 6 in PLOS One.

The public is invited to a free lecture called "Exotic Earths: Exploring Planets Around Other Stars" by NASA astrobiologist Avi Mandell at the Library of Congress, Washington, D.C. The free lecture will be held on Wednesday, June 19, at 11:30 a.m. EDT in the Pickford Theater of the Library of Congress.

Kepler-22b is the first transiting planet to have been detected in the habitable-zone of its host star. At 2.4 Earth radii, Kepler-22b is too large to be considered an Earth-analog, but should the planet host a moon large enough to maintain an atmosphere, then the Kepler-22 system may yet possess a telluric world.

Watch the final student presentations for the SETI Institute's USRA (Undergraduate Research at the SETI Institute in Astrobiology) program with San Jose State University.

As part of an international team of exoplanets hunters, astronomers at the University of Arizona are developing a technique to detect faint dust clouds around other stars, many of which might hide Earth-like planets.

Astronomer John Gizis of the University of Delaware, working with data obtained by the Kepler mission, is studying a highly unusual dwarf star and its powerful flares that may hold clues to the likelihood of life on other planets as well as to the behavior of our Sun.

On May 28, 2013, NASA's Kepler mission delivered new data to the NASA Exoplanet Archive. We sat down with Michael Haas, Kepler science office director at NASA Ames Research Center, to find out more.