Adam Kovac
It doesn’t take a rocket scientist to make important astronomical discoveries. Sometimes, all it takes is an internet connection and some spare time.
That’s all Tom Bickle, Martin Kabatnik, and Austin Rothermich needed to find a celestial object rocketing through the Milky Way at roughly one million miles (1.6 million kilometers) per hour. The trio were participants in Backyard Worlds: Planet 9, an online collaboration wherein volunteers look at images captured by NASA’s recently retired Wide-field Infrared Survey Explorer (WISE). The goal is to identify objects at the edge of the solar system, such as brown dwarfs (balls of gas too big to be planets, but too small to be stars), low-mass stars, and even a hypothesized ninth planet orbiting the Sun.
The photos sent to the citizen scientists were actually processed from WISE’s infrared cameras, which scans wavelengths of light invisible to human eyes. The volunteers analyzed series of photos of the same objects taken about five years apart, which enabled them to filter out stars that are too distant to be of interest, and also potential glitches from WISE’s instruments.
In one such series, Bickle, Kabatnik, and Rothermich noticed an object moving in the images. They reported their findings through the Backyard Worlds portal. Scientists followed up their finding by looking at the object through the University of Hawaii’s Near-Infrared Echellette Spectrometer telescope, and was given the name CWISE J1249.
A team of scientists from NASA, UC San Diego, and several other universities set out to examine the data. In a pre-print paper that’s been accepted for publication in the Astrophysical Journal Letters, they wrote that, while it’s not clear what CWISE J1249 actually is, its characteristics make it likely to either be a small star or a brown dwarf. Whatever it is, it’s moving fast, with what the researchers called “a unique trajectory and speed.” So fast, it appears it will eventually break free of the gravitational pull of the Milky Way and shoot off into intergalactic space.
It’s not just the speed that’s unusual. The data indicates CWISE J1249 contains less iron and other metals than other observed stars and brown dwarfs, which could mean it’s a very old object, dating back to the early days of the Milky Way.
“I can’t describe the level of excitement,” said Kabatnik, who lives in Nuremberg, Germany, in a statement. “When I first saw how fast it was moving, I was convinced it must have been reported already.”
As for why the object is moving so fast, Kyle Kremer, an incoming professor at UC San Diego who worked on the paper, explained it could have been part of a binary system, but got slingshotted outward when its partner went supernova. Another explanation is that it started as part of a globular cluster (a large collection of stars), but had a near encounter with a pair of black holes, “the complex dynamics” of which “can toss that star right out of the globular cluster.”
It may seem as though the three citizen scientists have gotten a raw deal, since the object isn’t named after them (at least, not yet). Don’t feel too bad. The trio are listed among the study’s authors, so they’ve got some pretty cool bragging rights at their next work Christmas party.