Ultraluminous X-ray Source

Black Holes

Neutron Star Powers Ultraluminous X-rays

It turns out that neutron stars — not black holes — power at least some ultraluminous X-ray sources.

ULX in M82

Stellar Science

No Big Black Hole for Two ULXs

Two new studies suggest that ultraluminous X-ray sources are not all created by beefy black holes.

Black Holes

X-ray Outburst in Spiral Galaxy M83

Astronomers have spotted an unusual "ultraluminous" burst of X-rays coming from the otherwise barren region between the grand spiral arms of Messier 83.