In a major astronomical development, a group of researchers took direct images of a baby exoplanet in the process of becoming a gas-giant several times more massive than Jupiter.

The newborn world, now named PDS 70b, was found orbiting a 5.4 million-year-old dwarf star called PDS 70, some 370 light years away from Earth. The stellar body was already suspected of having a planet in its vicinity, but the theory was not confirmed until researchers from Max Planck Institute for Astronomy, Germany, turned to European Southern Observatory’s Very Large Telescope.

The idea behind detection, as widely theorized, was to take close observation of the protoplanetary disk surrounding the star. This region contains gas and dust leftover from star formation and serves as hotbeds for planetary formation.

Baby exoplanet
This spectacular image from the SPHERE instrument on ESO's Very Large Telescope is the first clear image of a planet caught in the very act of formation around the dwarf star PDS 70. The planet stands clearly out, visible as a bright point to the right of the centre of the image, which is blacked out by the coronagraph mask used to block the blinding light of the central star. ESO/A. Müller et al.

In this particular case, astronomers had witnessed a strange gap in the disk suggesting that a planet might be forming in the veil of dust. The theory was confirmed when the team photographed the disk and found the baby planet at the inner rim of the gap in question.

The object, according to the team, is cleaving a path through the material present in the disc. It can be seen on the right side of a central black spot, which is the dwarf star. The research team decided to mask the stellar body so that the light from the planet could be deduced from the ground-based observatory.

The technique worked perfectly and even allowed the group to delve into the physical and atmospheric properties of the planet.

According to the data collected, PDS 70b is probably a growing gas-giant, which takes some 120 years to orbit its star and is a few times more massive than Jupiter. The temperatures on the distant world go beyond 1000 degrees Celsius — more than any planet in our solar system — and it also shrouded by clouds that alter the radiation emitted by its core. The team also stressed the planet sits roughly three billion kilometers away from the star, which further confirms the theory that massive gas-giants form in the outer reaches of a star system.

We have discovered thousands of exoplanets — many even sit in the so-called potentially habitable or “goldilocks” zone — but finding a world in the process of formation holds major importance because it could give scientists critical insight into the processes involved in the formation of baby planets in protoplanetary discs.

“These discs around young stars are the birthplaces of planets, but so far only a handful of observations have detected hints of baby planets in them,” Miriam Keppler, who led the team behind the discovery of PDS 70’s still-forming planet. “The problem is that until now, most of these planet candidates could just have been features in the disc.”

The study titled “Discovery of a planetary-mass companion within the gap of the transition disk around PDS 70,” was published July 2 in the journal Astronomy & Astrophysics.