This result has implications for the study of exoplanets and their habitability.
In space there are several situations that could endanger planets like Earth, such as asteroids or black holes, among others. But now, astronomers using data from NASA’s Chandra X-ray Observatory
and other telescopes have identified a new threat
.This is a phase during which intense X-rays from exploding stars can affect planets more than 100 light-years away. This result has implications for the study of exoplanets and their habitability, NASA reports in a statement.
This newly discovered threat comes from the shock wave of a supernova hitting the dense gas surrounding the exploded star, as shown at the top right of our artist’s impression. When this impact occurs, it can produce a large dose of X-rays that reaches an Earth-like planet (shown at bottom left, illuminated by its out-of-sight host star at right) months to years after the explosion and can last for decades. Such intense exposure can trigger an extinction event on the planet.
A new study reporting on this threat is based on X-ray observations of 31 supernovae and their aftermath, primarily from NASA’s Chandra X-ray Observatory, ESA’s Swift and NuSTAR and XMM-Newton missions, showing that the Planets can be subjected to lethal doses of radiation located about 160 light-years away. Prior to this, most research on the effects of supernova explosions had focused on the hazard of two periods: the intense radiation produced by a supernova in the days and months after the explosion, and the energetic particles that arrive hundreds or thousands of years later.
If a torrent of X-rays sweeps across a nearby planet, the radiation could seriously alter the planet’s atmospheric chemistry. For an Earth-like planet, this process could remove a significant portion of the ozone, which ultimately protects life from dangerous ultraviolet radiation from its host star. It could also lead to the disappearance of a wide range of organisms, especially marine ones at the bottom of the food chain, which would lead to an extinction event, details Europa Press. After years of lethal X-ray exposure from the interaction of the supernova and the impact of ultraviolet radiation from the host star of an Earth-like planet, a large amount of nitrogen dioxide is likely to be produced, causes a brown haze in the atmosphere. “Greening” of land masses could also occur due to damage to plants.
4 of the 31 supernovae in the study. POT There is strong evidence, including the detection in different parts of the world of a type of radioactive iron, that there were supernovae near Earth between 2 and 8 million years ago. The researchers estimate that these supernovae were between 65 and 500 light-years away from Earth.