An unusually bright and productive galaxy 4 billion light years away has been discovered with the help of two Mauna Kea observatories.
The hulking galaxy, located in the heart of a larger galaxy cluster, is rapidly spitting out 860 new stars a year, according to press releases from the W.M. Keck and Canada-France-Hawaii telescopes, which helped find or confirm the discovery.
In comparison, our Milky Way galaxy produces a meager one or two stars a year.
This unusual amount of activity is attributed to a “train wreck of a merger” with a smaller galaxy. The collision ignited a fury of new stars with the help of the additional gas, CFH said.
“Usually, the stars at the centers of galaxies clusters are old and dead, essentially fossils,” said lead study author Tracy Webb in a written statement. “But we think the giant galaxy at the center of this cluster is furiously making new stars after merging with a smaller galaxy.”
The presence of condensed pockets of gas, known as “beads on a string,” where stars are forming helped lead researchers to that conclusion.
Shredded remnants of the absorbed, smaller galaxy can be seen in a wispy tail extending outward, researchers say.
Keck said the discovery is the first to show that such giant galaxies at the heart of clusters can grow significantly from gas stolen from other galaxies.
Galaxy clusters are vast families of galaxies tied by gravity. This cluster, researchers say, has at least 27 galaxy members and nearly 400 trillion stars.
Our Milky Way galaxy resides in a small galaxy group, which is on the edge of the Laniakea supercluster of 100,000 galaxies. Laniakea is Hawaiian for “immeasurable heaven.”
The object first was found with CFH and the Spitzer space telescope. The discovery was confirmed with the help of the Keck Observatory, which hosts the world’s largest and most powerful optical telescopes.
On Tuesday, CFH also announced it found evidence of a giant Jupiter-like exoplanet orbiting a star 15 times closer than the Earth orbits the sun. The star is 450 light years away in the Taurus stellar nursery.
The discovery provides preliminary evidence that these “hot Jupiters” might be far more frequent around very young stars, the observatory said.
Email Tom Callis at tcallis@hawaiitribune-herald.com.