Scientists have discovered thousands of exoplanets, including dozens of terrestrial—or rocky—worlds in the habitable zones around their parent stars. A promising approach to search for signs of life on these worlds is to probe exoplanet atmospheres for "biosignatures"—quirks in chemical composition that are telltale signs of life. For example, thanks to photosynthesis, our atmosphere is nearly 21% oxygen, a much higher level than expected given Earth's composition, orbit and […]

Emerging technologies and new strategies are opening a revitalized era in the Search for Extraterrestrial Intelligence (SETI). New discovery capabilities, along with the rapidly-expanding number of known planets orbiting stars other than the Sun, are spurring innovative approaches by both government and private organizations, according to a panel of experts speaking at a meeting of the American Association for the Advancement of Science (AAAS) in Seattle, Washington.

A new study led by the University of Hawai'i (UH) at Mānoa has helped refine understanding of the amount of hydrogen, helium and other elements present in violent outbursts from the Sun, and other types of solar "wind," a stream of ionized atoms ejected from the Sun.

Planetary scientists using the Atacama Large Millimeter/submillimeter Array (ALMA) revealed the secrets of the atmosphere of Titan, the largest moon of Saturn. The team found a chemical footprint in Titan's atmosphere indicating that cosmic rays coming from outside the Solar System affect the chemical reactions involved in the formation of nitrogen-bearing organic molecules. This is the first observational confirmation of such processes, and impacts the understanding of the intriguing […]

NASA has selected four Discovery Program investigations to develop concept studies for new missions. Although they're not official missions yet and some ultimately may not be chosen to move forward, the selections focus on compelling targets and science that are not covered by NASA's active missions or recent selections. Final selections will be made next year.