astronomy Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest includ ...

, Calvera (also known as 1RXS J141256.0+792204) is an X-ray source in the constellation

Ursa Minor Ursa Minor (, contrasting with Ursa Major), also known as the Little Bear, is a constellation located in the far northern celestial hemisphere, northern sky. As with the Great Bear, the tail of the Little Bear may also be seen as the handle of ...

, identified in 2007 as an isolated

neutron star A neutron star is the gravitationally collapsed Stellar core, core of a massive supergiant star. It results from the supernova explosion of a stellar evolution#Massive star, massive star—combined with gravitational collapse—that compresses ...

. It is one of the hottest and closest of its kind to Earth. It is named after the villain in the 1960 film '' The Magnificent Seven'', as it is the eighth such neutron star known within 500 parsecs of Earth, and the seven previously discovered isolated neutron stars are called 'The Magnificent Seven'. There is a ring of radio emission almost a degree in diameter, offset about 4′.9 from Calvera itself; it is very likely its

supernova remnant A supernova remnant (SNR) is the structure resulting from the explosion of a star in a supernova. The supernova remnant is bounded by an expanding shock wave, and consists of ejected material expanding from the explosion, and the interstellar mat ...

References

External links

* Universe Today
Closest Neutron Star Discovered
*

Pennsylvania State University The Pennsylvania State University (Penn State or PSU) is a Public university, public Commonwealth System of Higher Education, state-related Land-grant university, land-grant research university with campuses and facilities throughout Pennsyl ...

. Neutron stars Ursa Minor ROSAT objects Stars with proper names {{star-stub