A mysterious cosmic object, moving at an incredible speed through the Milky Way, at over a million kilometers per hour, has been intercepted by amateur scientists, professional astronomers and students. They are all participating in NASA’s “Backyard Worlds: Planet 9” project, which aims to search for planets and brown dwarfs beyond the orbit of Neptune. The discovery, published in the journal Astrophysical Journal Lettersrepresents another success of Citizen Science, science participated in by citizens.
The mysterious object, with a mass similar to that of a small star, is moving so fast that it is destined to leave our galaxy to continue its race in interstellar space. Its images were captured by NASA’s WISE telescope, which mapped the sky in infrared light between 2009 and 2011. The mission then continued as NeoWise from 2013 to 2024.
The mysterious object, designated CWISE J124909.08+362116.0, was spotted by citizen science veterans Martin Kabatnik, Thomas P. Bickle, and Dan Caselden, who co-authored the paper. The discovery was later confirmed by observations with several ground-based telescopes. “When I first saw how fast it was moving, I thought someone had already described it,” said Kabatnik, who analyzed the images from his home in Nuremberg, Germany.
One of the most common hypotheses at the moment is that it is a brown dwarfan object whose mass is between that of a giant planet and that of a star like the Sun. Although brown dwarfs are not rare – 4,000 have already been discovered as part of the “Backyard Worlds: Planet 9” project – none of these threaten to leave the Milky Way.
Observations by the Keck Observatory in Hawaii also indicate that CWISE J124909.08+362116.0 It has much less iron than other stars, suggesting that it may be quite old, perhaps one of the first generations of stars in our galaxy. However, it remains a mystery why it is moving so fast: it may have been part of a binary system in which one of the two stars exploded as a supernova, or it may have drifted away from a globular cluster after interacting with a black hole.