Earth's closest alien planet may not be alone, after all. A study reported that Proxima Centauri has a dusty ring, which may suggest the presence of other planets along with Proxima B.
The Lone Exoplanet
Located approximately 4.2 light-years away from Earth, within the southern constellation of The Centaur, Proxima Centauri is a red dwarf star identified in 2016 to have starspots cycles. The European Southern Observatory previously reported that the dwarf star hosts a lone exoplanet, Proxima B, which is highly similar to planet Earth.
Early studies found that Proxima B exoplanet contains a surface temperature that supports the liquid form of water. It also has the possibility of being a habitable planet. However, NASA quashed the possibility of it being the "next Earth." Scientists revealed that the frequency of stellar eruptions from the nearby red dwarf stars, which release significant amounts of radiation, may damage its atmosphere by depleting the oxygen supply.
The recent identification of the dusty ring using the Atacama Large millimeter/submillimeter Array (ALMA) network of telescopes in Chile suggests the Earth may have more than one alien neighbor.
"This result suggests that Proxima Centauri may have a multiple planet system with a rich history of interactions that resulted in the formation of a dust belt," said Guillem Anglada, lead author and astronomer at the Instituto de Astrofisica de Andalucia in Spain.
Dust belts like this are highly suggestive of presence of planets. Astronomers believe that these are residues of materials that fail to form as new planets.
Anglada explained that this particular discovery is important as this is the first evidence that indicates the existence of an elaborate planetary system surrounding the star nearest to the sun.
The team of researchers also found out that the dusty belt, located a few hundred million kilometers from the star, has a mass equal to about 1 percent of the Earth's. Its temperature is almost the same as that of the Kuiper Belt's.
Potential Exploration Programs
Further research into the shape of the dust ring can provide the astronomers a better understanding of the Proxima B, particularly its mass. The Breakthrough Starshot exploration project, set to zoom past the exoplanet can also help out in mapping the dust environment.
"These first results show that ALMA can detect dust structures orbiting around Proxima," study coauthor Pedro Amado stated. "Further observations will give us a more detailed picture of Proxima's planetary system."
The team also noted (PDF) a possible dust ring located about 10 times farther from the star. Described as an extremely cold belt with a 45 degree tilted orbital plane.