Collaborative work of citizen scientists and professional astronomers has resulted into a discovery of what is believed to be the oldest known planet-forming disk ever spotted till date.
Astronomers say that this will act as an unusual hunting ground for exoplanets for it is a star surrounded by the oldest known circumstellar disk, which can be considered to be a primordial ring of gas and dust that orbits around a young star and from which planets can form as the material collides and aggregates. The discovery is quite remarkable because not only are red dwarf star with a warm circumstellar disk rare, but the star has had the disk for exceptionally long time. Astronomers say that most of such disks fade away in about 30 million years, but this particular one has been around for 45 million years.
The work was carried out by citizen scientists from Disk Detective, a project led by NASA/GSFC’s Dr. Marc Kuchner that’s designed to find new circumstellar disks and professional astronomers at various institutes and universities.
Determining the age of a star can be tricky or impossible. But the Carina association, where this red dwarf was found, is a group of stars whose motions through the Galaxy indicate that they were all born at roughly the same time in the same stellar nursery. Carnegie’s astronomers devised a test that showed this newly found red dwarf and its disk are likely part of the Carina association, which was key to revealing its surprising age.
Knowing that this star and its disk are so old may help scientists understand why M dwarf disks appear to be so rare. This star and its disk are interesting for another reason: the possibility that it could host extrasolar planets. Most of the extrasolar planets that have been found by telescopes have been located in disks similar to the one around this unusual red dwarf. Moreover, this particular star is the same spectral type as Proxima Centauri, the Sun’s nearest neighbor, which was shown to host at least one exoplanet, the famous Proxima b, in research published earlier this year.
Findings have been published in the Astrophysical Journal Letters.