Using two of the agency’s X-ray telescopes, researchers were able to zoom in on a dead star’s erratic behavior as it released a bright, brief burst of radio waves.

In a recent study published in The Astrophysical Journal, researchers report a first-of-its-kind measurement of a ULX taken with NASA's Nuclear Spectroscopic Telescope Array (NuSTAR). The finding confirms that these light emitters are indeed as bright as they seem and that they break the Eddington limit.

NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR), led by Caltech and managed by JPL, turned 10 years old in June. This space telescope detects high-energy X-ray light and studies some of the most energetic objects and processes in the universe.

What remains of the star that exploded just outside our galaxy in 1987? Debris has obscured scientists’ view, but two of NASA’s X-ray telescopes have revealed new clues.

Astronomers tend to have a slightly different sense of time than the rest of us. They regularly study events that happened millions or billions of years ago, and objects that have been around for just as long. That's partly why the recently discovered neutron star known as Swift J1818.0-1607 is remarkable: A new study in the journal Astrophysical Journal Letters estimates that it is only about 240 years old - a veritable newborn by cosmic standards.

Bachetti and collaborators recently published a comprehensive, multi-year study of the pulsation history of M82 X-2, the first example of the new class of extremely luminous X-ray binary that NuSTAR discovered in 2014.

Astronomers are observing the changes in the accretion disk around the neutron star X-ray binary 4U 1608-52. The system was tracked as it fades from outburst to quiescence by three NASA space telescopes, with NuSTAR observations suggesting that the disk puffs up and becomes transparent as the outburst fades.

NASA's NuSTAR X-ray observatory saw a flash of light that could be produced only by an extremely energetic event. Scientists are investigating what could have caused the flare.

In the nearby Whirlpool galaxy and its companion galaxy, M51b, two supermassive black holes heat up and devour surrounding material. These two monsters should be the most luminous X-ray sources in sight, but a new study using observations from NASA's NuSTAR mission shows that a much smaller object is competing with the two behemoths.

A Caltech-led astronomy team is homing in on the nature of extreme objects known as ultraluminous X-ray sources.