NASA's Hubble discovers Cloud 9, universe's first confirmed failed galaxy

The National Aeronautics and Space Administration (NASA) has identified a one-of-a-kind cosmic object.

It is a dark, starless cloud enriched in gas and dominated by dark matter. Named as “Cloud-9,” the object is the first confirmed example of what scientists call a Reionization-Limited H I Cloud (RELHIC), a long theorised remnant from the universe’s earliest era of galaxy formation.

It is located about 14 million light-years from Earth near the spiral galaxy Messier 94 (M94). Cloud-9 appears to be a “failed galaxy.” Unlike normal galaxies, it has no stars at all despite holding a large amount of neutral hydrogen gas.

The cloud was first detected in observations from ground-based radio telescopes, including the Very Large Array (VLA). However, only Hubble’s Advanced Camera for Surveys was capable of confirming that the cloud is truly starless.

Principal investigator Alejandro Benitez-Llambay of the University of Milano-Bicocca stated, “This is a tale of a failed galaxy. Seeing no stars is exactly what proves the theory right.”

Cloud 9’s hydrogen core spans about 4,900 light-years and contains gas roughly one million times the mass of the Sun. Scientists estimates its total mass, dominated by dark matter, to be around five billion solar masses.

This places Cloud-9 in a rare “sweet spot” since it is massive enough to survive for billions of years but not massive enough to collapse and form stars.

As noted by researchers, RELHICs form shortly after the Big Bang, when intense radiation prevents small dark matter halos from gathering enough gas to ignite star formation. It is anticipated that most of such relics have vanished, making Cloud-9 an exceptional find.