Astrobiology

Image: Drill core of shales and siltstones. Brown layers are tell-tale sign of an iron-rich ancient ocean. Credit: Peter McGoldrick, University of Tasmania

Over the last half-billion years, the ocean mostly has been full of oxygen and teeming with animal life. But earlier, before animals evolved, oxygen was harder to come by. Now a new study, led by researchers at the University of California, Riverside (UCR), reveals that the ancient deep ocean was not only devoid of oxygen but also rich in iron, a key biological nutrient for nearly a billion years longer than previously thought--right through a key evolutionary interval that culminated in the first rise of animals.

Russian cosmonaut Sergei Volkov, Expedition 28 flight engineer, checks the progress of a new growth experiment on the BIO-5 Rasteniya-2 (Plants-2) payload with its LADA-01 greenhouse in the Zvezda Service Module of the International Space Station. ISS028-E-034854 (31 Aug. 2011) --- high res (1.2 M) low res (91 K)

Aims: In this study we assess the habitability of HD85512b, a 3.6M_Earth planet orbiting a K5V star. The radial velocity data and orbital parameters for HD 85512 b have just been published, based on data from the dedicated HARPS-upgrade GTO program.

Our solar system, where planets have a range of sizes and move in near-circular paths, may be rather unusual, according to a German-British team led by Professor Pavel Kroupa of the University of Bonn. The astronomers, who publish their model in the journal Monthly Notices of the Royal Astronomical Society, find that forming planetary systems may be knocked around by crashes with nearby clumps of material, leading to systems where planets have highly inclined orbits and where the smaller (and potentially habitable) worlds are thrown out completely.

A team of astronomers, using the Spitzer Space Telescope, have reported the first extragalactic detection of the C70 fullerene molecule, and the possible detection of planar C24 ("a piece of graphene") in space. Letizia Stanghellini and Richard Shaw, members of the team at the National Optical Astronomy Observatory in Tucson, Arizona, describe how collisional shocks powered by the winds from old stars in planetary nebulae could be responsible for the formation of fullerenes (C60 and C70) and graphene (planar C24). The team is led by Domingo Anibal Garcia-Hernandez of the Instituto de Astrofisica de Canarias in Spain and includes international astronomers and biochemists.

The Herschel Space Observatory's large telescope and state-of-the-art infrared detectors have provided the first confirmed finding of oxygen molecules in space. The molecules were discovered in the Orion star-forming complex.

Individual atoms of oxygen are common in space, particularly around massive stars. But, molecular oxygen, which makes up about 20 percent of the air we breathe, has eluded astronomers until now.