This Planet Smells Funny

An artist's concept of GJ 436b peeking out from behind its parent star, an M-dwarf much cooler than the sun.

Giant planet GJ 436b in the constellation Leo is missing something.

Would you believe swamp gas?

To the surprise of astronomers who have been studying the Neptune-sized planet using NASA’s Spitzer Space Telescope, GJ 436b has very little methane (CH4).
“Methane should be abundant on a planet of this temperature and size, but we found 7000 times less methane than what the models predict,” says Kevin Stevenson of the University of Central Florida (UCF). Stevenson was lead author of a paper reporting the result in the April 22, 2010, issue of Nature.

Source: [NASA Science News]

September 15, 2010 / Posted by: Daniella Scalice

Tracking Viruses Back in Time

Capsids of Bacteriophage T4 virus particles retain their characteristic shape after being coated with silica. Credit: Jim Laidler
How long have viruses been around? No one knows. Ken Stedman, associate professor of biology at Portland State University and co-chair of the astrobiology Focus Group on Viruses, is working to change that. Stedman and his colleagues are trying to determine what kinds of biosignatures viruses leave behind in the environment. Their work could help astrobiologists understand the origin and evolution of viruses on Earth, and aid in identifying virus biosignatures on other worlds. The study was recently published in the journal Astrobiology.

Source: [astrobio.net]

September 6, 2010 / Written by: Henry Bortman

What Life Leaves Behind

In 1976, NASA’s twin Viking landers arrived on Mars, equipped with four experiments designed to offer foolproof evidence of life on the Red Planet. They were looking for biosignatures, or fingerprints of life. As they took their first scoops of Martian soil, the whole world held its breath.

Source: [SEED Magazine]

December 3, 2009 / Posted by: Daniella Scalice

Scarce Shelter on Mars

Microbes that hitch a ride on a spacecraft might make it all the way to Mars, but a recent study finds they probably won’t survive for very long there. A team of researchers at NASA’s Kennedy Space Center has been freezing, irradiating and generally pummeling microbes with harsh living conditions in an attempt to understand how life may or may not survive on Mars. The results of the research will be used in developing effective contamination controls for future missions, and may also help scientists understand how to search for biosignatures on Mars.

Source: [Astrobiology Magazine]

June 4, 2009 / Written by: Jeremy Hsu

Biosignatures in Ancient Rocks Workshop Proceedings Now Available

In September, 2007, an NAI co-sponsored workshop entitled “Biosignatures in Ancient Rocks” was held in Ontario, Canada. Spearheaded by experts in the field, workshop attendees heard lectures, participated in discussions, and examined field sites toward a greater understanding of early Earth biosignatures, what the remaining major questions and problems are, and how they can be answered and solved. The proceedings from the workshop are available in the current issue of Astrobiology.

January 20, 2009 / Posted by: Daniella Scalice

Extracellular Protein-Metal Aggregates: A New Biosignature?

Deep inside a flooded mine in Wisconsin, scientists from NAI’s University of California, Berkeley Team have discovered an environment in which bacteria emit proteins that sweep up metal nanoparticles into immobile clumps. Their finding may lead to innovative ways to remediate subsurface metal toxins, and have exciting implications for identifying biosignatures on Earth and other worlds. The research, published in the June 14th issue of Science, was done in collaboration with a team from the U.S. Department of Energy’s Lawrence Berkeley National Laboratory.

Source: [Link]

June 14, 2007 / Posted by: Shige Abe