Penn State researchers have discovered an extraordinarily massive planet orbiting an ultracool dwarf star, challenging existing theories of planet and star formation. Named LHS 3154b, the planet’s mass is over 13 times that of Earth, while its host star, LHS 3154, has a mass significantly lower than the sun.
The massive planet was spotted using an astronomical spectrograph built at Penn State by a team of scientists led by Suvrath Mahadevan. This instrument, called the Habitable Zone Planet Finder (HPF), was designed to detect planets orbiting the coolest stars outside our solar system with the potential for having liquid water on their surfaces.
The discovery of LHS 3154b raises questions about prior understandings of the formation of stars and planets. The current theories of planet formation have trouble accounting for what the researchers have discovered, according to Megan Delamer, a graduate student at Penn State.
The new finding prompts a reassessment of star and planet formation processes, challenging current survey work with the HPF and other instruments. The team’s measurements would require a larger amount of solid material in the planet-forming disk than current models would predict.
“This discovery really drives home the point of just how little we know about the universe,” said Suvrath Mahadevan, the Verne M. Willaman Professor of Astronomy and Astrophysics at Penn State and co-author on the paper.
Penn State researchers are now rethinking existing planet formation theories and are examining the implications of this discovery in further detail. The discovery of the planet LHS 3154b has exceeded all expectations and has provided an extreme test case for all existing planet formation theories.