Royal Astronomical Society | 2016 Jan 25
[img3="False colour infrared image of TYC 9486-927-1 and 2MASS J2126. The arrows show the projected movement of the star and planet on the sky over 1000 years. The scale indicates a distance of 4000 Astronomical Units (AU), where 1 AU is the average distance between the Earth and the Sun. Credit: 2MASS/S. Murphy/ANU"]http://www.ras.org.uk/images/stories/pr ... fig_au.jpg[/img3][hr][/hr]A team of astronomers in the UK, USA and Australia have found a lonely planet, until now thought to be a free floating or lonely planet, in a huge orbit around its star. Incredibly the object, designated as 2MASS J2126, is about 1 trillion (1 million million) kilometres from the star, or about 7000 times the distance from the Earth to the Sun. The researchers report the discovery in a paper in Monthly Notices of the Royal Astronomical Society.
In the last five years a number of free floating planets have been found. These are gas giant worlds like Jupiter that lack the mass for the nuclear reactions that make stars shine, so cool and fade over time. Measuring the temperatures of these objects is relatively straightforward, but it depends on both mass and age. This means astronomers need to find out how old they are, before they can find out if they are lightweight enough to be planets or if they are heavier 'failed stars' known as brown dwarfs.
US-based researchers found 2MASS J2126 in an infrared sky survey, flagging it as a possible young and hence low mass object. In 2014 Canadian researchers identified 2MASS J2126 as a possible member of a 45 million year old group of stars and brown dwarfs known as the Tucana Horologium Association. This made it young and low enough in mass to be classified as a free-floating planet.
In the same region of the sky, TYC 9486-927-1 is a star that had been identified as being young, but not as a member of any known group of young stars. Until now no one had suggested that TYC 9486-927-1 and 2MASS J2126 were in some way linked. ...
Lonely Planet Finds a Mum a Trillion Km Away
Australian National University | via Space Daily | 2016 Jan 26
A Nearby Young M Dwarf with a Wide, Possibly Planetary-Mass Companion - Niall R Deacon, Joshua E Schlieder, Simon J Murphy
- arXiv.org > astro-ph > arXiv:1601.06162 > 22 Jan 2016