Newly-Forming Baby Planet – labeled PDS 70b

[ilan]

Astronomers see a baby planet growing
Paul Scott Anderson in SPACE | August 24, 2018

They’ve confirmed for the 1st time that this newly formed planet – labeled PDS 70b – is still gathering material from the dust and gas around its star. They’re literally watching this new world develop and grow.

Actual image of young star PDS 70 by SPHERE, a planet-hunting instrument on ESO’s Very Large Telescope. The newly-forming baby planet – labeled PDS 70b – can be seen as the bright spot inside the gap in the surrounding disk of dust and gas.

For the first time, astronomers have caught a baby planet in the process of growing. This isn’t just a newly developing planet, located in a gap in a star’s disk of primordial dust and gas. That’s been done before. This is direct evidence that such a planet is still gathering material from the star’s surrounding disk, and thus that it’s growing larger. The results were just published in a new peer-reviewed paper in The Astrophysical Journal Letters.

Such young worlds have been found before, but now scientists can confirm that this one, a gas giant world called PDS 70b, is actively accumulating material from the circumstellar disk in which it resides.

Last month, astronomers announced that PDS 70b was the first newly forming planet to ever be directly imaged. The planet orbits the relatively young, 10-million-year-old orange dwarf star called PDS 70. This star and its planet are 370 light-years from Earth. The planet can be seen within a gap in the star’s circumstellar disk.

Such gaps have been seen many time in recent years. They are direct evidence that astronomers’ theories about star- and planet-formation are correct, and that material in a disk of dust and gas surrounding a star is starting to form into planets, leaving a gap or gaps in the disk as the planets’ own gravities begin to sweep up rocky debris.

But seeing the actual forming planets themselves has been difficult, at least until recently. According to Miriam Keppler, who led the team behind the discovery of PDS 70b:

These disks around young stars are the birthplaces of planets, but so far only a handful of observations have detected hints of baby planets in them. The problem is that until now, most of these planet candidates could just have been features in the disc.