пятница, 13 декабря 2019 г.

NASA’s NICER Delivers Best-ever Pulsar Measurements, 1st Surface Map

ISS - NICER - SEXTANT Mission patch.

Dec. 12, 2019

Astrophysicists are redrawing the textbook image of pulsars, the dense, whirling remains of exploded stars, thanks to NASA’s Neutron star Interior Composition Explorer (NICER), an X-ray telescope aboard the International Space Station. Using NICER data, scientists have obtained the first precise and dependable measurements of both a pulsar’s size and its mass, as well as the first-ever map of hot spots on its surface. 

 Neutron star Interior Composition ExploreR or NICER. Image Credit: NASA

The pulsar in question, J0030+0451 (J0030 for short), lies in an isolated region of space 1,100 light-years away in the constellation Pisces. While measuring the pulsar's heft and proportions, NICER revealed that the shapes and locations of million-degree “hot spots” on the pulsar’s surface are much stranger than generally thought.

“From its perch on the space station, NICER is revolutionizing our understanding of pulsars,” said Paul Hertz, astrophysics division director at NASA Headquarters in Washington. “Pulsars were discovered more than 50 years ago as beacons of stars that have collapsed into dense cores, behaving unlike anything we see on Earth. With NICER we can probe the nature of these dense remnants in ways that seemed impossible until now.”

A series of papers analyzing NICER’s observations of J0030 appears in a focus issue of The Astrophysical Journal Letters and is now available online.