A giant world discovered around a small star is taking a new turn on how planets form.
Astronomers say they have found a Jupiter-like planet orbiting a star that is only 12% of the mass of our sun. There may even be another large planet of gas lurking in this system, which is 31 light years away.
The Spanish-led team wrote this week in Science magazine that the newly confirmed planet didn't graduate in the usual and gradual waywhere a solid nucleus of particles forms before gas accumulates. Instead, surprising scientists, the planet appears to have sprung directly from gas.
Lead author Juan Carlos Morales from the Catalan Institute of Space Studies said the planet could be almost as big as its star. A "year" about 200 days ago.
"It was very exciting to find this planet because it was completely unexpected," said Morales. The results indicate that "a new population of massive planets may also exist around low mass stars."
The 3.5-meter telescope at the Calar Alto Observatory in Spain, where observations were made that led to the discovery of an unusual planetary star system.
(Pedro Amado / Marco Azzaro – IAA / CSIC)
Morales and his team maintain that the gravitational instability in a young star's gas and dust disc can in some cases result in the rapid formation of huge gas planets – even when the star is tiny.
This new world is "an extraordinary candidate" for this process, he said. Hubert klahr from the Max Planck Institute of Astronomy in Germany, part of the research team. "This discovery leads us to revise our models."
In a companion article, Yale University astronomer Greg Laughlin, who did not participate in the study, pointed out that more than 4,000 so-called exoplanets were confirmed in solar systems outside of ours. While another new in itself is no longer particularly noteworthy, he said: “the one who defies current theories of planet formation can cheer up astronomers. "
The planet orbiting this particularly small and cold red dwarf star, officially known as GJ 3512, is at least half the mass of Jupiter. Scientists cannot measure its dimensions, but the models indicate that it may be comparable to Jupiter's size, according to Morales.
Using observatories in Spain, the researchers repeatedly studied the oscillating motion of the star to identify the planet in its uneven orbit.
The star is so weak that it barely entered the group's research. Scientists needed more small stars for sampling, so they added some at the last minute.
"We were lucky to do so, otherwise we would never have made that discovery." Ignasi Ribas, director of the Institute of Space Studies of Catalonia, said in a statement.
Morales and his colleagues are looking for a second planet orbiting this dwarf star. There may have been a third planet that was ejected from the system a long time ago, they noted.