New observations suggest that Fomalhaut b, a world located 25 light years and whose existence was doubted by scientists, is real.
The exoplanet Fomalhaut b, located in the constellation Pisces Austrinos to 25 light years from Earth, was discovered in November 2008 by the sharp Hubble view. It was the first world photographed in visible light around another
star. It was there, hidden inside a huge ring of debris around its host star. However, many scientists reject the existence of the planet, they thought impossible. Without more evidence in its favor, Folmalhaut bwas removed from the list of new worlds discovered beyond the solar system. But the planet has reappeared. A review of data from the Hubble has revived the hypothesis of its existence. The study suggests that it is a rare and possibly unique world that is completely surrounded by dust.
When discovered, Fomalhaut b was the first exoplanet to be imaged directly, within the visible spectrum, around another star. The object appeared just inside a huge ring of debris surrounding an offset of the host star. The state of the planet and its mass-no more than three times that of Jupiter seemed adequate for its gravity to explain the appearance of the ring.
Recent studies have argued that this interpretation is incorrect planetary. Based on the apparent motion of the object and the absence of infrared detection by the Spitzer Space Telescope at NASA, stated that the object is nothing but a cloud of dust is not related to any planet.
A new analysis, however, leads to the conclusion that this planet has back to life. “Although our results seriously challenge the original discovery, do so in a way that actually clarify the interpretation of the object, leaving intact the main conclusion that Fomalhaut b is a massive planet,” says Thayne Currie, an astronomer at the University of Toronto.
In the original study, it was said that the brightness of Fomalhaut b varied by a factor of two, evidence that the planet was adding gas. But other research later interpreted this variability as evidence that the object was actually a cloud of dust in a transient.
In the new study, scientists reanalyzed the Hubble observations of the star from 2004 to 2006. Unlike previous research, the team discovered that the planet was kept constant brightness. The team attempted to detect Fomalhaut b in the infrared using the Subaru Telescope in Hawaii, but could not. Subaru and Spitzer could not detect imply thatFomalhaut b must be less than twice the mass of Jupiter.
Another controversial issue has been the object’s orbit. If Fomalhaut b is responsible for displacement of the ring, then must follow an orbit aligned with the ring and move to its lower speed. The speed described in the original study appeared to be too fast. In addition, some researchers argued that Fomalhaut b is an inclined orbit passing through the ring plane.
Using data from the Hubble, the team states that Fomalhaut b Currie moves with a speed and a direction consistent with the original idea thatthe planet’s gravity is changing the ring. “Given what we know about the behavior of dust and environment in which the planet is, we think we’re seeing a planetary object that is fully integrated into the powder instead of a dust cloud that floats freely, “says team member John Debes, an astronomer at the Space Telescope Science Institute in Baltimore, Maryland.