NASA has recently discovered a newborn exoplanet — meaning a fully-formed planet that orbits a star other than the sun. Astronomers say it could help us better understand the formation of planets in general. The planet, dubbed K2-33b, is the youngest fully formed exoplanet ever detected.
The Christian Science Monitor reports:
K2-33b is about 50 percent larger than Neptune – six times the size of the Earth – and is a mere 5 to 10 million years old, making it the youngest fully formed exoplanet ever detected.
Compared to the Earth, which is a “middle-aged” planet at about 4.5 billion years old, “you might think of [K2-33b] as an infant,” Trevor David, a graduate student working with astronomer Lynne Hillenbrand at the California Institute of Technology (Caltech), and lead author of a new study published online Monday in the journal Nature, said in a press release.
“With K2-33b, we’re getting a glimpse of planet formation as it occurs,” said Erik Petigura of the California Institute of Technology, also an author of the study published in Nature. “Astronomers have believed for some time that gaseous planets need to form in the first 10 million years of their star’s lifetime. K2-33b provides some of the best direct proof of this theory.”
Phys.org adds:
Andrew Mann (University of Texas at Austin), the first author of the study, is intrigued by these results, because how and when close-in planets achieve their orbital radii may affect the outcome of terrestrial planet formation. "If Jupiter or Neptune had migrated inward after the terrestrial planets formed, it seems unlikely that our Solar System would have an Earth, or any of the terrestrial planets at all," he speculated.
