(NewsNation) — Citizen scientists have discovered a fast-moving object on a trajectory to escape the Milky Way and shoot into intergalactic space.
They used data from NASA’s WISE telescope to discover the object, which is moving fast enough it will be able to escape the galaxy’s gravity. It’s the first such object discovered to have the mass of a small star.
NASA’s Wide Field Infrared Explorer (WISE) telescope mapped the sky in infrared light between 2009 to 2011. It was later reactivated as NEOWISE from 2013 to August 2024.
Backyards Worlds citizen scientists Martin Kabatnik, Thomas P. Bickle and Dan Caselden spotted the faint object, known as CWISE J124909.08+362116.0 (we’ll call it CWISE for short) in WISE images. They followed up using several ground-based telescopes to confirm the discovery and co-authored a paper in the Astrophysical Journal Letters.
“I can’t describe the level of excitement,” said Kabatnik, a citizen scientist from Nuremberg, Germany. “When I first saw how fast it was moving, I was convinced it must have been reported already.”
CWISE is moving at one million miles per hour, but the speed isn’t its only distinguishing feature. It also has a low mass, which makes it difficult to classify.
It could possibly be a low-mass star or a brown dwarf, which doesn’t steadily fuse hydrogen in its core and is somewhere between a gas giant planet and a star.
While brown dwarfs aren’t rare, with more than 4,000 discovered by Backyard Worlds volunteers, but this is the only one discovered that is zooming out of our galaxy.
Another unique property is that CWISE appears to have much less iron and other metals than most stars and brown dwarfs, based on data from the W.M. Keck Observatory in Maunakea, Hawaii.
That suggests it could be not only fast but also very old, potentially from one of the first generations of stars in the Milky Way.
It’s also not entirely clear why CWISE is moving so fast. One theory is that it originally came from a binary system with a white dwarf that exploded as a supernova when it pulled too much material from its companion.
Another theory is that it came from a tightly bound cluster of stars and had a chance encounter with a pair of black holes that sent it flying away. Scientists are hoping that taking a closer look at CWISE’s elemental composition will help narrow down the answer.
The volunteer citizen scientists also collaborated with professors and students to examine the findings and write the paper.