RX J1856.5-3754

Starbox image


caption = X-ray image of RX J1856.5-3754Starbox observe
epoch=1996.7
equinox=J2000.0
constell=Corona Australis
ra=RA|18|56|35 [http://www.astro.sunysb.edu/fwalter/NS/ns.html RX J185635-3754 - an Isolated Neutron Star] , F. M. Walter, web page at the Department of Physics and Astronomy, State University of New York at Stony Brook. Accessed on line June 29, 2007.]
dec=DEC|-37|54|36
appmag_v=~25.6Starbox detail
mass=0.9
radius=1.9 - 4.1 km
luminosity=?
temperature=?
metal=?
rotation=?
age=1 million Starbox reference
Simbad=1ES+1853-37.9

RX J1856.5-3754 (also called RX J185635-3754, RX J185635-375, and various other designations) is a nearby neutron star. It is believed to have been created by a supernova explosion of its companion star about one million years ago and is moving 108 km/s across the sky. It was discovered in 1992, and observations in 1996 appeared to confirm that it was a neutron star, the closest neutron star to Earth yet discovered. It was originally thought to be about 150–200 light-years away, but further observations using the Chandra X-ray Observatory in 2002 appear to show that its distance is greater—about 450 light-years. It was once proposed that RX J1856.5-3754 was too small to be a neutron star and may therefore in fact be a quark star (see also 3C58). However, this theory is not currently considered to have much supporting evidence.Fact|date=May 2007

References

* http://jumk.de/astronomie/special-stars/rx-j185635-375.shtml
* Walter, Frederick M.; Lattimer, James M., The Astrophysical Journal, 2002

External links

* [http://www.spaceref.com/news/viewpr.html?pid=2580 The Mystery of the Lonely Neutron Star] , European Southern Observatory press release, September 11, 2000. Accessed online at spaceref.com May 20, 2007.
* [http://www.space.com/scienceastronomy/astronomy/runaway_star_001110.html Closest Known Neutron Star Races Across Sky] (space.com)
* [http://arxiv.org/abs/astro-ph/0204159 Is RX J185635-375 a Quark Star?]
* [http://antwrp.gsfc.nasa.gov/apod/ap020414.html APOD: 2002 April 14 - RX J185635-375: Candidate Quark Star]
* [http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2004ApJ...603..265T Bare Quark Stars or Naked Neutron Stars? The Case of RX J1856.5-3754]
* [http://www.astro.sunysb.edu/fwalter/NS/ns.html RX J185635-3754 - an Isolated Neutron Star]
* [http://hubblesite.org/newscenter/archive/releases/star/neutron-star/1997/32/image/a/ News Release STScI-1997-32: Hubble Sees a Neutron Star Alone in Space]