NASA's Chandra Observatory continues to search for life beyond Earth
NASA's Chandra X-ray Observatory and the European Space Agency's XMM-Newton are being used by astronomers to explore the potential habitability of exoplanets. The research is focused on the radiation emitted by nearby stars, to determine if an exoplanet orbiting those stars could support life. The study is led by Breanna Binder, an astronomer from California State Polytechnic University, who emphasizes the importance of understanding X-rays from host stars in determining a planet's habitability.
X-ray emissions from nearby stars under observation
The team has analyzed 57 nearby stars, focusing on the brightness and energy of their X-ray emissions and output fluctuation due to stellar flares. Sarah Peacock, a research scientist from the University of Maryland, highlighted, "We have identified stars where the habitable zone's X-ray radiation environment is similar to or even milder than the one in which Earth evolved. "Such conditions may play a key role in sustaining a rich atmosphere like the one found on Earth," she added.
Potential impact on exoplanet atmospheres
High levels of X-rays and ultraviolet light could potentially harm an exoplanet's atmosphere, reducing its ability to support life. Binder stated, "Without characterizing X-rays from its host star, we would be missing a key element on whether a planet is truly habitable or not." "We need to look at what kind of X-ray doses these planets are receiving," she claimed. The team's research aims to shed light on this aspect of exoplanet habitability.
Over 5,500 exoplanets discovered so far
While only some of the 57 stars studied have known habitable exoplanets, it is believed that there are many more yet to be discovered. To date, over 5,500 exoplanets have been discovered with nearly 10,000 more candidates currently under evaluation. It is estimated that there could be billions of exoplanets in the Milky Way galaxy alone, providing a vast potential for further research into extraterrestrial life.
X-ray data to guide future exploration
Edward Schwieterman, an astrobiologist at the University of California, highlighted the importance of X-ray data in refining and prioritizing targets for future exploration. He stated, "We don't know how many planets similar to Earth will be discovered in images with the next generation of telescopes, but we do know that observing time on them will be precious and extremely difficult to obtain." The X-ray data could potentially expedite the discovery of Earth-like planets.
