Astronomers have discovered a giant planet that, by all accounts, should not exist.
The mysterious gaseous world is unusually large compared to its host star, the nearby red dwarf GJ 3512.
“Around such stars there should only be planets the size of the Earth or somewhat more massive Super-Earths,” according to Christoph Mordasini, professor at the University of Bern and member of the National Center of Competence in Research (NCCR) PlanetS.
“GJ 3512b, however, is a giant planet with a mass about half as big as the one of Jupiter,” he said in a statement. “And thus at least one order of magnitude more massive than the planets predicted by theoretical models for such small stars.”
The exoplanet was detected by Spanish-German research consortium CARMENES, which used the Doppler technique to monitor the back-and-forth motion of stars orbited by one or more planets.
“The star was showing a rather strange behavior very early on,” Juan Carlos Morales, a researcher from the Institute of Space Studies of Catalonia (IEEC) at the Institute of Space Sciences, said.
“Its velocity was changing very rapidly,” he continued, “and consistently in both wavelength channels of the instrument, indicating the presence of a massive companion, an anomalous feature for a red dwarf.”
Exoplanet GJ 3512b was discovered by the CARMENES consortium with an instrument installed at the Calar Alto Observatory in southern Spain (via Pedro Amado/Marco Azzaro/IAA/CSIC)
This star, however, almost didn’t make it onto the list of observational targets.
“Initially, this star was not included in our observation list because it was too faint,” project scientist Ignasi Ribas said. “We then realized we didn’t have enough small stars in the sample and we added a few, at the very last minute.
“We were lucky to do so because otherwise we would have never made this discovery,” he added.
A discovery that still baffles scientists the world over.
“Our model predicts that there should be no giant planets around such stars,” Mordasini insisted.
Well, sir, your model appears to be wrong.
Planets are typically formed by the gradual growth of small bodies into ever larger masses—the “bottom-up process.”
But what if the giant planet GJ 3512b was formed instead by a different mechanism? One that we shall call a “top-down process”: A part of the gas disk in which the planets are formed collapses under its own gravitational force.
Even this explanation poses problems, though.
“The planet GJ 3512b is therefore an important discovery that should improve our understanding of how planets form around such stars,” Mordasini said.
More on Geek.com:
- NASA Telescope’s ‘Starglasses’ Make It Easier to Spot Exoplanets
- Water Vapor Detected on Potentially ‘Habitable’ Planet
- Astronomers Discover Planet With Strange, Egg-Shaped Orbit
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