Hunt for Planet 9: how you can help NASA search for brown dwarfs and low-mass stars

NASA scientists are trying to find new planets. And they need your help. 

Through its new website, Backyard Worlds: Planet 9, NASA invites the average star-gazer to study grainy images of space in search of undiscovered worlds.

Between 2010 and 2011, NASA’s Wide-field Infrared Survey Explorer (WISE) mission scanned the entire sky to create the most complete survey of mid-infrared wavelengths to date. But the images gathered from the WISE mission still need to be studied.

“There are too many images for us to search through ourselves,” NASA said in a statement.

Citizen-scientists will look for real celestial objects such as brown dwarfs and low-mass stars. And if they are fortunate, participants may find one of two big-ticket discoveries: a star closer to the sun than its current neighbor Proxima Centauri, or maybe even the sun’s ninth planet. 

“There are just over four light-years between Neptune and Proxima Centauri, the nearest star, and much of this vast territory is unexplored,” lead researcher Marc Kuchner, an astrophysicist at NASA’s Goddard Space Flight Center, said in a press release. “Because there’s so little sunlight, even large objects in that region barely shine in visible light. But by looking in the infrared, WISE may have imaged objects we otherwise would have missed.” 

The Backyard Worlds: Planet 9 team says that technology is not advanced enough to analyze all of WISE’s images: they need the human eye.

“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,” University of California, Berkeley postdoctoral researcher Aaron Meisner, a physicist who specializes in analyzing WISE images, said in a press release.

The moving pictures are full of “blurry blobs of light,” called “ghosts.” These ghosts can move around, change color, and ultimately fool NASA’s analysis software.

“But with your powerful human eyes, you can help us recognize real objects of interest that move among these artifacts,” says the project’s website. “You’ll be able to tell what objects are real by the way they move around differently from the artifacts.” 

Through the Backyard Worlds: Planet 9 website, anyone can study WISE’s images and tag moving objects that could potentially be more than a ghost. Professional astronomers will later follow-up on the tagged objects and use their expertise to see if a new discovery was made. And if any scientific publication comes of this project, the citizen-scientist will receive shared credit. 

By inviting the masses to comb through its data, NASA might even find the next Clyde Tombaugh. 

In 1930, American astronomer Mr. Tombaugh spent hours staring into a device called a “blink comparator” that tracks the movement of objects between two separate photographic plates – a strategy similar to the one employed by NASA today. And Tombaugh’s hard work paid off: after 7,000 hours of study, he discovered Pluto.

Finding a ninth planet would be very difficult – but not necessarily impossible. 

In 2016, California Institute of Technology astronomers Mike Brown and Konstantin Batygin found indirect evidence that a ninth planet could exist beyond Pluto. According to their calculations, Planet 9 would be 10 times larger than Earth and 1,000 times farther away from the sun. Just last month, a study from New Mexico State University suggested that Planet Nine could be a “rogue planet,” recently sucked in by the sun’s gravitational pull.