A new image taken with the Atacama Large Millimeter/submillimeter Array (ALMA) reveals an exoplanet that can potentially form moons. This discovery was made by astronomers at the Harvard & Smithsonian Center for Astrophysics. The new observations were published recently in The Astrophysical Journal Letters.
The region that was found in the image is called a circumplanetary disk, which is similar to the rings around Jupiter. The astronomers found that this region is a region where moons and other satellites that revolve the planet form. While these results were tentative, ALMA made it possible for it to be confirmed.
“Our work presents a clear detection of a disk in which satellites could be forming,” says Myriam Benisty, a researcher at the University of Grenoble and the University of Chile who led the research using the Atacama Large Millimetre/submillimetre Array (ALMA). “Our ALMA observations were obtained at such exquisite resolution that we could clearly identify that the disk is associated with the planet and we are able to constrain its size for the first time.”
The picture also reveals that the diameter of the disk is comparable to the distance from the Sun to the Earth. This could be useful in the future as this distance could provide an estimation of the distance needed to create planets and other celestial bodies.
“We used the millimeter emission from cool dust grains to estimate how much mass is in the disk and therefore, the potential reservoir for forming a satellite system around PDS 70c,” says Sean Andrews, a study co-author and astronomer at the Center for Astrophysics (CfA).
The planet forming process also utilizes the circumplanetary disk, except it is the one that revolves around a sun. The small planet gathers mass as it travels around this disk which later becomes a planet that creates a disk of its own. This disk also helps regulate the amount of mass going into the planet.
“More than 4,000 exoplanets have been found until now, but all of them were detected in mature systems. PDS 70b and PDS 70c, which form a system reminiscent of the Jupiter-Saturn pair, are the only two exoplanets detected so far that are still in the process of being formed,” explains Miriam Keppler, researcher at the Max Planck Institute for Astronomy in Germany and one of the co-authors of the study.
The images taken by ALMA and the results from the astronomers are certainly a discovery that will be remembered.