Astronomers may have identified giant planets in the dust around young stars
A new NASA study has suggested that gigantic spiral patterns seen around very young stars may be a telltale sign of gigantic, unseen planets in their orbit. If proved accurate, the theory would allow for a new method of planet detection, while providing an invaluable look at planet birth.
Astronomers have identified thousands of planets orbiting distant stars, but getting a look at the earliest stages of their formation is tricky, due to the thick disk of gas and dust that surrounds them as they form.
The new research proposes that we can identify planets in the disk around young parent stars by looking for gravitational disturbances in the vast swathes of material. Specifically, it's thought that the presence of giant planets may cause large-scale spiral arms around young stars, themselves generally just a few million years old.
Looking at two young stars (designated SAO 206462 and MWC 758), the team developed computer simulations of the stars and disks, modelling the effect that young giant planets would have if present.
In the simulation, the planets cause higher density regions of gas and dust that build up, and as the disk rotates around the star, form huge spiral arms. Those structures closely resemble features found in observations made by the European Southern Observatory's (ESO) Very Large Telescope (VLT).
The simulations also indicate that the spiral arms could provide a wealth of information about the presumed planets, including their mass. They also suggest that the planets theorized to be orbiting SAO 206462 and MWC 758 would have to be truly huge – a minimum of 10 times the mass of Jupiter.
The idea could have ground-breaking implications, but we'll have to wait until next generation installations like the James Webb Space Telescope before we can observe the predicted planets, and confirm (or disprove) the theory. If it's proved correct, it could significantly improve our understanding of the universe.
"There are many theories about how planets form but very little work based on direct observational evidence confirming these theories," says researcher Ruobing Dong. "If you see signs of a planet in a disk right now, it tells you when, where, and how planets form."
The findings of the research were published in The Astrophysical Journal Letters.