Growing baby planet captured for first time in dark circle

The planet, named WISPIT 2b, is outside our Solar System and embedded in a cleared gap of a multi-ringed disc of dust and gas.

The researchers, led by University of Arizona astronomer Laird Close and Richelle van Capelleveen, an astronomy graduate student at Leiden Observatory in the Netherlands, discovered the unique exoplanet using powerful telescopes.

WISPIT 2b, labeled a protoplanet because it is accumulating material and growing into a fully realized planet, is a gas giant about five times as massive as Jupiter.

The massive protoplanet is around 5 million years old, or almost 1,000 times younger than the Earth, and about 437 light-years from Earth.

These masses were inferred, in part, from the thermal infrared light observed by the University of Arizona’s 8.4-metre Large Binocular Telescope on Mount Graham in south-eastern Arizona with the help of U of A astronomy graduate student Gabriel Weible.

Gabriel Weible said: "It's a bit like what our own Jupiter and Saturn would have looked like when they were 5,000 times younger than they are now.

"The planets in the WISPIT-2 system appear to be about 10 times more massive than our own gas giants and more spread out. But the overall appearance is likely not so different from what a nearby 'alien astronomer' could have seen in a 'baby picture' of our Solar System taken 4.5 billion years ago."

Laird Close added: "Dozens of theory papers have been written about these observed disc gaps being caused by protoplanets, but no one's ever found a definitive one until today.

"It's been a point of tension, actually, in the literature and in astronomy in general, that we have these really dark gaps, but we cannot detect the faint exoplanets in them.

"Many have doubted that protoplanets can make these gaps, but now we know that in fact, they can."

The discovery is detailed in papers published in the Astrophysical Journal Letters.