What happens to planets as their stars age and come closer to death? This is what a recent study published in the Monthly Notices of the Royal Astronomical Society hopes to address as a team of researchers investigated the interaction between stars near the end of their lifetimes and their exoplanets with short-period orbits. This study has the potential to help scientists better understand the evolution of stars and what this could mean for our Sun near the end of its lifetime.
For the study, the researchers analyzed data obtained from NASA’s Transiting Exoplanet Survey Satellite (TESS) mission for short-period exoplanets orbiting post-main-sequence stars, which are stars approximately the size of our Sun which have exhausted their hydrogen and have ballooned into red giants. Additionally, these short-period exoplanets have orbits that last mere days.
The goal of the study was to ascertain the influence of these red giants on their planetary populations, with the researchers settling on 130 exoplanets after careful data analysis. In the end, the researchers found that only 0.28 percent of older post-main sequence stars had giant exoplanets, with 0.35 percent of younger post-main-sequence stars having giant exoplanets. Finally, the researchers found only 0.11 percent of the oldest post-main-sequence stars had exoplanets.
Artist's illustration of an exoplanet being swallowed by its post-main-sequence star. (Credit: International Gemini Observatory/NOIRLab/NSF/AURA/M. Garlick/M. Zamani)
“This is strong evidence that as stars evolve off their main sequence they can quickly cause planets to spiral into them and be destroyed,” said Dr. Edward Bryant, who is an Astrophysics Prize Fellow at the University of Warwick and lead author of the study. “This has been the subject of debate and theory for some time but now we can see the impact of this directly and measure it at the level of a large population of stars. We expected to see this effect but we were still surprised by just how efficient these stars seem to be at engulfing their close planets.”
With our Sun currently a main-sequence star, this study demonstrates how our own solar system could evolve as our Sun nears the end of its lifetime billions of years from now.
What new insight into near-death stars will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Monthly Notices of the Royal Astronomical Society, EurekAlert!