Planet’s orbit discovered by Hertfordshire astronomers

Infrared image of star and planet - Image credit to Simon Murphy from Australian National University (Image: Archant)

A team of astronomers from the University of Hertfordshire, USA and Australia discovered that the planet, which was previously believed to be a ‘lonely’ or ‘free-floating’ planet, is in fact orbiting a distant star.

The planet, called a 2Mass J2126, is about one trillon (one million million) kilometres from the star, which is about 7000 times the distance from the Earth to the Sun. The researchers reported the discovery in a paper in Monthly Notices of the Royal Astronomical Society.

Lead author Dr Niall Deacon of the University of Hertfordshire has spent the last few years searching for young stars with companions in wide orbits. As part of the work, his team looked through lists of known young stars, brown dwarfs and free-floating planets to see if any of them could be related.

They found that the star TYC 9486-927-1 and 2MASS J2126 are moving through space together and are both about 104 light years from the Sun, implying that they are associated.

Infrared image of the star and the planet - Image credit to Simon Murphy from Australian National University (Image: Archant)

“This is the widest planet system found so far and both the members of it have been known for eight years,” said Dr Deacon, “but nobody had made the link between the objects before. The planet is not quite as lonely as we first thought, but it’s certainly in a very long distance relationship.”

It takes 2Mass J2126 roughly 900,000 years to complete one orbit, meaning it has completed less than fifty orbits over its lifetime. There is little prospect of any life on the planet, but any inhabitants would see their ‘Sun’ as no more than a bright star, and might not even imagine they were connected to it at all.

Projected movement of the star and the planet - Image credit to Simon Murphy from Australian National University (Image: Archant)