RX J0822−4300
Star fragment in the constellation Puppis / From Wikipedia, the free encyclopedia
RX J0822−4300, often referred to as a "Cosmic Cannonball", is a radio-quiet neutron star currently moving away from the center of the Puppis A supernova remnant at over 3 million miles per hour (5 400 000 km/h; 1500 km/s; ~0.5% the speed of light), making it one of the fastest moving stars ever found. Astronomers used NASA's Chandra X-ray Observatory to observe the star over a period of five years to determine its speed. At this velocity the star will be ejected from the galaxy millions of years from now.
Observation data Epoch 1952 (equinox J2000.0)[1] Equinox 1952 (equinox J2000.0)[1] | |
---|---|
Constellation | Puppis |
Right ascension | 08h 23m 8.16s[2] |
Declination | −42° 41′ 41.4″[2] |
Apparent magnitude (V) | ~24[2] |
Astrometry | |
Radial velocity (Rv) | 672 km/s |
Distance | 2,000 pc |
Galactic coordinates | 260.3841 −03.4718 |
Other designations | |
Database references | |
SIMBAD | data |
Although the cosmic cannonball is not the only hypervelocity star discovered, it is unique in the apparent origin of its speed. Others may have derived theirs from a gravitational slingshot around the Milky Way's suspected supermassive black hole, Sagittarius A*. Current theories fail to explain how such speeds can be attained from a supernova explosion. It could be a possible quark star.
However, a more recent (2012) analysis by the same group yielded a more modest recoil velocity of 672±115 km/s which is much less problematic theoretically.[3]