An artist’s conception shows Planet X, a.k.a. Planet Nine. (Carnegie Institution / Robin Dienel)
Citizen scientists can join an online hunt for icy worlds, brown dwarfs and other yet-to-be-discovered objects beyond the orbit of Neptune, using a technique that’s not all that different from the method that led to Pluto’s discovery 87 years ago.
“Backyard Worlds: Planet 9” could even lead to the discovery of a super-Earth that may (or may not) be hidden on the solar system’s far frontier. The icy world known as Planet Nine or Planet X is only theoretical for now, but its existence would explain some of the puzzles surrounding the weird orbits of some far-out objects.
The “Backyard Worlds” website offers up millions of mini-movies that incorporate infrared imagery from NASA’s Wide-field Infrared Survey Explorer, or WISE. The movies show the same patch of sky at different times, going back and forth like a flipbook.
The project involves getting volunteers to watch the movies and look for telltale changes in the positions of points of light between one view and the other. Promising prospects are flagged for a follow-up look by professional astronomers.
Back in 1930, Lowell Observatory astronomer Clyde Tombaugh used a contraption known as a blink comparator to flip between photographic plates. The desk-sized device helped him spot a dot that turned out to be the dwarf planet Pluto.
Today, computers conduct similar analyses of images much more quickly to identify dwarf planets, asteroids and the failed stars known as brown dwarfs. But sometimes the software gets tripped up by image artifacts, and sometimes human vision can pick up on the patterns that computers miss.
The organizers of “Backyard Worlds” are counting on that human factor.
“There are just over four light-years between Neptune and Proxima Centauri, the nearest star, and much of this vast territory is unexplored,” the project’s lead researcher, Marc Kuchner of NASA’s Goddard Space Flight Center, said in a news 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.”
Participants will win a share of the credit in any scientific discoveries that the project brings to light.
“‘Backyard Worlds: Planet 9′ has the potential to unlock once-in-a-century discoveries, and it’s exciting to think they could be spotted first by a citizen scientist,” Berkeley team member Aaron Meisner said in today’s news release.
The project is a collaboration involving NASA, the University of California at Berkeley, the American Museum of Natural History in New York, Arizona State University, the Space Telescope Science Institute in Baltimore, and Zooniverse.
Are far-out planets not your thing? There’s more to choose from: Zooniverse has pioneered lots of other online citizen science projects over the years, including Galaxy Zoo, Ancient Lives and Fossil Finder.