Using the Atacama Large Millimetre/submillimetre Array (ALMA) in Chile, astronomers have spotted a young star forming like a planet.

Star Found Just Beyond Protoplanetary Disc Of Another Star

John Ilee, from the University of Leeds, and colleagues were observing the young massive star MM 1a and the rotating disc of gas and dust around it when they discovered another object.

The object, which was orbiting MM 1a just beyond the disc, turned out to be a young star and dubbed MM 1b.

The researchers think is one of the first examples of a fragmented disc detected around a massive young star.

Birth Of Stars And Planets

Ilee explained that stars form within large clouds of gas and dust in interstellar space, and when these collapse under gravity, the star starts to rotate faster and form a disc around them.

In low mass stars such as the sun, this rotating disc of dust and gas eventually develops into planets and asteroids.

The star and protoplanetary disc that Ilee and colleagues observed, however, is so massive that instead of a planet forming in the disc, the researchers saw another star being formed.

By measuring the amount of radiation coming from the dust and the shifts in frequency of light emitted by the gas, the researchers determined the mass of both stars. They found that MM 1a is 40 times more massive than the sun.

The smaller orbiting star, on the other hand, weighs less than half the solar mass. llee said that this is unusual because while many older massive stars have nearby companions, binary stars are usually equal in mass and likely formed together as siblings.

"Finding a young binary system with a mass ratio of 80:1 is very unusual, and suggests an entirely different formation process for both objects," llee said.

Capable Of Forming Own Planetary System

The researchers said that the young star MM 1b may also be surrounded by its own circumstellar disc that may potentially form planets.

The process, however, should happen fast since stars as massive as MM 1a only last for around a million years before they explode as supernovae. This means that while MM 1b may be capable of forming its own planetary system, it would not exist for long.

The findings were published in the Astrophysical Journal Letters.