Chandra May Have First Evidence of a Young Star Devouring a Planet
Tuesday, July 24, 2018
News Feature

Scientists, including Scott Wolk from the Harvard-Smithsonian Center for Astrophysics, may have witnessed the destruction of a young planet or planets for the first time using data from NASA's Chandra X-ray Observatory. If this discovery is confirmed (depicted in this artist's illustration), it would give insight into the processes affecting the survival of infant planets.

RW Aur A is a star about 450 light years from Earth, making it relatively nearby. Since the 1930s, astronomers have studied RW Aur A and been curious about why the optical light from this star changes over time. In recent years, scientists have observed that this variability has increased, with the star dimming even more and for longer periods of time.

To investigate this mystery, a team of astronomers used Chandra to get information in the X-ray band of the electromagnetic spectrum. X-rays are generally emitted by more energetic and hotter phenomena than their optical light counterparts and can reveal information about different elements, including iron.

The Chandra data suggest that the most recent dimming event from RW Aur A was caused by the collision of two "planetesimals" (that is, infant planetary bodies still in the process of formation), including at least one object large enough to be a planet.