NASA hails citizen scientists for spotting object speeding out of Milky Way at 1 mn miles an hour

This artist's concept shows a hypothetical white dwarf, left, that has exploded as a supernova. The object at right is CWISE J1249, a star or brown dwarf ejected from this system as a result of the explosion. This scenario is one explanation for where CWISE J1249 came from. (Image credit: https://science.nasa.gov/; W.M. Keck Observatory/Adam Makarenko)

NASA announced on August 15 that citizen scientists, or common people who help out the space agency with scientific projects, have found a rare and fast-moving object that is set to escape the Milky Way’s gravity and enter the intergalactic space.

This object, called CWISE J124909.08+362116.0, is unique because it has a mass similar to or less than that of a small star, making it the first of its kind to be discovered.

NASA highlighted the significance of CWISE J1249’s speed and low mass. “CWISE J1249 is zooming out of the Milky Way at about 1 million miles per hour. But it also stands out for its low mass, which makes it difficult to classify as a celestial object," it said.

NASA explained that the discovery was made using images from its Wide Field Infrared Explorer (WISE) mission, which originally mapped the sky in infrared light between 2009 and 2011.

Citizen scientists Martin Kabatnik, Thomas P Bickle, and Dan Caselden were credited with spotting the faint, fast-moving object in the WISE images. NASA said their discovery was later confirmed by scientists through follow-up observations using ground-based telescopes. NASA noted the importance of their contribution. “These citizen scientists are now co-authors on the team’s study about this discovery published in the Astrophysical Journal Letters.”

Ordinary brown dwarfs, which are objects between a gas giant planet and a star, are not rare, as Backyard Worlds, NASA-funded citizen science project volunteers, have discovered over 4,000 of them. However, NASA pointed out that “none of the others are known to be on their way out of the galaxy.”

Another unusual characteristic of this object is its composition. NASA explained that “ it has much less iron and other metals than other stars and brown dwarfs. This unusual composition suggests that CWISE J1249 is quite old, likely from one of the first generations of stars in our galaxy".

On why this object is moving at such a high speed, NASA discussed possible scenarios. “One hypothesis is that CWISE J1249 originally came from a binary system with a white dwarf, which exploded as a supernova when it pulled off too much material from its companion. Another possibility is that it came from a tightly bound cluster of stars called a globular cluster, and a chance meeting with a pair of black holes sent it soaring away.”

To better understand the object's origins, NASA stated that “Scientists will look more closely at the elemental composition of CWISE J1249 for clues about which of these scenarios is more likely.”

This discovery, as NASA emphasised, was the result of a collaborative effort. “This discovery has been a team effort on multiple levels—a collaboration involving volunteers, professionals, and students,” NASA said, acknowledging the contributions of other citizen scientists like Melina Thévenot and Frank Kiwy, whose software was instrumental in the finding.