Astronomers have spotted possible formation of planets around a distant star 400 light-years from Earth using the Atacama Large Millimeter/submillimeter Array (ALMA).
The star is relatively young and has planetary disc around it with at least three grooves of which at least two are believed to have been carved out by planets that are still developing. The star named HD 163296 is roughly 5 million years old and its mass is twice that of our Sun. Andrea Isella, an astronomer at Rice University in Houston, and colleagues, observed the star and based on their observations claim that they have compelling evidence that suggest that there are at least two planets that are forming around the star.
Each of these planets are believed to be the size of Saturn and located at a distance of 100 AU and 160 AU from the star. One astronomical unit is the average distance from the Earth to the Sun. The two planets are very far from the central star – well beyond the extent of our solar system’s Kuiper Belt, the region of icy bodies beyond the orbit of Neptune.
The astronomers have claimed existence of two planets based on an appreciable dip in the amount of CO in the outer two dust gaps. By seeing the same features in both the gas and the dust components of the disk, the astronomers believe they have found compelling evidence that there are two planets coalescing remarkably far from the central star. The width and depth of the two CO gaps suggest that each potential planet is roughly the same mass as Saturn.
In the gap nearest to the star, the team found little to no difference in the concentration of CO gas compared to the surrounding dusty disk. This means that the innermost gap could have been produced by something other than an emerging planet. Researchers say that while it is certainly possible that the ringed structures around the star are the result of a nascent planet plowing through the dust, they do not rule out possibilities of something else that would have done this; however, the new observations using ALMA provide intriguing evidence that planets are indeed forming around this one young star.