In a remarkable achievement, NASA's citizen science program has led to the discovery of a hypervelocity object moving at an astonishing speed of 1 million miles per hour.
This object, which has a mass similar to or less than that of a small star, is traveling so fast that it will eventually escape the Milky Way's gravity and enter intergalactic space. The discovery, made as part of NASA's Backyard Worlds: Planet 9 project, underscores the important role of citizen scientists in advancing our understanding of the universe.
NASA's Backyard Worlds Project and the Discovery of CWISE J1249
The Backyard Worlds: Planet 9 project allows volunteers to examine data from NASA's WISE mission, which originally mapped the sky in infrared light from 2009 to 2011. The project was reactivated as NEOWISE in 2013 and continued to provide invaluable data until its retirement in August 2024.
Citizen scientists Martin Kabatnik, Thomas P. Bickle, and Dan Caselden were instrumental in spotting a faint, fast-moving object—CWISE J124909.08+362116.0 (or "J1249" for short)—in the WISE images. Their discovery, confirmed through follow-up observations with ground-based telescopes, revealed an object unlike any other previously found. J1249's mass and speed make it difficult to classify as either a star or a brown dwarf, leading to significant debate among scientists.
A Unique Hypervelocity Object
While hypervelocity stars are rare, J1249 stands out for its low mass and composition, which includes much less iron and other metals than other stars. This unusual chemical signature suggests that the object may be from one of the first generations of stars in our galaxy, making it a potentially ancient relic of the early Milky Way.
Scientists believe that J1249 may have originated in a binary system with a white dwarf, which could have exploded as a supernova, propelling J1249 into its current hypervelocity. Another possibility is that the object originated in a globular cluster, where interactions with a pair of black holes could have sent it soaring through space.
Tracking a Hypervelocity Star with Citizen Science
In a related discovery, another hypervelocity star, also identified through the Backyard Worlds project, has been observed moving at 1.3 million miles per hour—nearly 0.1% the speed of light. Located just 400 light-years from Earth, this star, also known as CWISE J1249+36, is the nearest known hypervelocity star to our planet. Astronomers believe it is on a trajectory that may eventually cause it to leave the Milky Way.
Research led by Professor Adam Burgasser from the University of California, San Diego, focused on analyzing the star's composition using data from the W. M. Keck Observatory and other ground-based telescopes. Their findings suggest that J1249+36 is an L subdwarf, a class of very low-mass, cooler stars. The star's peculiar velocity and trajectory have led scientists to investigate whether it may have been ejected from a binary system after a supernova explosion or flung out of a globular cluster by the interaction of a black hole binary.
The Significance of Citizen Science in Modern Astronomy
These discoveries highlight the increasingly vital role of citizen scientists in astronomy. Projects like Backyard Worlds capitalize on the human ability to detect patterns in data, often surpassing what computer algorithms can achieve.
The collaborative efforts of volunteers, professional astronomers, and students are reshaping how we study the universe, bringing fresh perspectives and aiding in the discovery of previously unknown celestial objects.
The identification of hypervelocity objects like CWISE J1249 and J1249+36 opens up new questions about the origins of such stars and the dynamics of the Milky Way. Further research into their chemical composition may eventually reveal the systems from which these stars were launched, offering deeper insights into the history of our galaxy and the forces that shape it.