NASA is turning to the public for help in searching for the hypothetical ‘Planet 9’ on the edge of our Solar System.


Using a new website called Backyard Worlds: Planet 9, citizen scientists are being offered the chance to search through animated views of the sky captured by NASA’s Wide-field Infrared Survey Explorer (WISE) mission, in the hope of discovering potential planets or brown dwarves lurking beyond Neptune.

The space between Neptune, the outermost known planet in the Solar System, and our closest star Proxima Centauri is largely unexplored.

It is hoped that using the WISE infrared data will enable potential planets to be spotted in an area with very little sunlight.

Last year Caltech astronomers Mike Brown and Konstantin Batygin found indirect evidence for the existence of a ninth planet in the Solar System, hypothesising it to be of similar size to Neptune and a thousand times farther from the Sun than Earth is.

However, the existence of Planet 9 is still being debated, and this new project is the latest attempt to see if it does indeed exist.

“Automated searches don’t work well in some regions of the sky, like the plane of the Milky Way Galaxy, because there are too many stars, which confuses the search algorithm,” says physicist Aaron Meisner, who specialises in analysing WISE images.

“Using the powerful ability of the human brain to recognise motion may be luckier.”

WISE’s infrared images cover the whole of the sky six times over, and have already discovered hundreds of previously unknown brown dwarfs.

The data is now being presented so that citizen scientists can spot faint, moving objects and note them for further investigation by professional astronomers.


Visit the Backyard Worlds: Planet 9 website to access the WISE data, search for cosmic bodies and discuss your findings with fellow space hunters! Let us know how you get on via Twitter, Facebook or by dropping us an email.


Iain Todd BBC Sky at Night Magazine
Iain ToddScience journalist

Iain Todd is BBC Sky at Night Magazine's Content Editor. He fell in love with the night sky when he caught his first glimpse of Orion, aged 10.