stellar wind tagged posts

Image of starlight on exoplanet. Credit: Courtesy of NASA/JPL-Caltech.

Is there life beyond Earth in the cosmos? Astronomers looking for signs have found that our Milky Way galaxy teems with exoplanets, some with conditions that could be right for extraterrestrial life. Such worlds orbit stars in “habitable zones,” regions where planets could hold liquid water that is necessary for life as we know it. However, the question of habitability is highly complex. Researchers led by space physicist Chuanfei Dong of the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) and Princeton University have recently raised doubts about water on – and thus potential habitability of – frequently cited exoplanets that orbit red dwarfs, the most common stars in the Milky Way.

In two ...

In this artist’s illustration, the young Sun-like star Kappa Ceti is blotched with large starspots, a sign of its high level of magnetic activity. New research shows that its stellar wind is 50 times stronger than our Sun’s. As a result, any Earth-like planet would need a magnetic field in order to protect its atmosphere and be habitable. The physical sizes of the star and planet and distance between them are not to scale. Credit: M. Weiss/CfA

Nearly 4B years ago, life arose on Earth. Life appeared because our planet had a rocky surface, liquid water, and a blanketing atmosphere. But life thrived thanks to another necessary ingredient: the presence of a protective magnetic field...