Maunakea HI (SPX) Jan 14, 2022 Three newly-discovered planets have been orbiting dangerously close...
Three newly-discovered planets have been orbiting dangerously close to stars nearing the end of their lives.
Out of the thousands of extrasolar planets found so far, these three gas giant planets first detected by the NASA TESS Mission, have some of the shortest-period orbits around subgiant or giant stars.
Grunblatt, who earned his PhD from the University of Hawai?i Institute for Astronomy, added that "These observations offer new windows into planets nearing the end of their lives, before their host stars swallow them up." The researchers estimate that the planets have masses between 0.5 and 1.7 times Jupiter's mass, and sizes that range from slightly smaller to more than 1.6 times the size of Jupiter.
"We expect to find tens to hundreds of these evolved transiting planet systems with TESS, providing new details on how planets interact with each other, inflate, and migrate around stars, including those like our Sun," said Nick Saunders, a graduate student at UH IfA and co-author of the study.
The planets were first found in NASA TESS Mission full-frame image data taken in 2018 and 2019.
Grunblatt and his collaborators identified the candidate planets in TESS data, and then used W. M. Keck Observatory's High-Resolution Echelle Spectrometer on Maunakea, Hawai?i to confirm the existence of the three planets.
Current models of planet dynamics suggest that planets should spiral in toward their host stars as the stars evolve over time, particularly in the last 10 percent of the star's lifetime.
The wide variety of planet densities found in the study suggests that these planetary systems have been shaped through chaotic planet-to-planet interactions.
If these molecules are seen, the data would provide constraints on where these planets formed, and what sort of interactions had to occur to produce the planetary orbits we see today.
Continued monitoring of these systems with the NASA TESS telescope will constrain the rate at which these planets are spiraling into their host stars.