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Riga 38:
I dati rilevano una sorgente stabile di [[raggi X]], probabilmente alimentata da materiale inghiottito dal buco nero e proveniente dai resti della supernova o da una [[stella binaria]] compagna.
'''SN 1979C''' was a [[supernova]] about 50 million [[light-
On November 15, 2010 [[NASA]] announced that evidence of a [[black hole]] had been detected as a remnant of the supernova explosion. Scientists lead by Dr. Dan Patnaude from the [[Harvard–Smithsonian Center for Astrophysics]] in [[Cambridge, Massachusetts|Cambridge, MA]] evaluated data gathered between 1995 and 2007 from several [[space observatory|space based observatories]]. NASA's [[Chandra X-ray Observatory]], the [[Swift Gamma-Ray Burst Mission]], as well as the [[European Space Agency]]'s [[XMM-Newton]], and Germany's [[ROSAT]] all participated in the examination.<ref name="nasa">{{cite web|url=http://www.nasa.gov/home/hqnews/2010/nov/HQ_10-299_CHANDRA.html|title=NASA'S Chandra Finds Youngest Nearby Black Hole|date=Nov. 15, 2010|publisher=[[NASA]]|accessdate=2010-11-15|author=Trent Perrotto|coauthors=Janet Anderson, Megan Watzke}}</ref>
The researchers observed a steady source of [[X-ray]]s and determined that it was likely that this was material being fed into the object either from the supernova or a [[Binary system (astronomy)|binary]] companion. However, an alternative explanation would be that the X-ray emissions could be from the [[pulsar wind nebula]] from a rapidly spinning [[pulsar]], similar to the one in the center of the [[Crab Nebula]].<ref name="nasa"/> These two ideas account for several types of known X-ray sources. In the case of black holes the material that falls into the black hole emits the X-rays and not the black hole itself. Gas is heated by the fall into the strong [[gravitational field]].
SN 1979C has also been studied in the radio frequency spectrum. A [[light curve]] study was performed between 1985 and 1990 using the [[Very Large Array]] radio telescope in [[New Mexico]].<ref name="astro">{{cite journal |author=Weiler, K. W.|coauthors=van Dyk, S. D., Discenna, J. L., Panagia, N., & Sramek, R. A. |year=1991 |title=The 10 year radio light curves for SN 1979C |journal=Astrophysical Journal, Part 1 (ISSN 0004-637X)|volume= vol. 380|pages=p. 161-166 |url=http://adsabs.harvard.edu/full/1991ApJ...380..161W }}</ref>
▲SN 1979C was a supernova about 50 million light-years away in Messier 100, a spiral galaxy in the constellation Coma Berenices. The Type II supernova was discovered April 19, 1979 by Gus Johnson, a school teacher and amateur astronomer.[2] This type of supernova is known as a core collapse and is the result of the internal collapse and violent explosion of a large star. A star must have at least 9 times the mass of the Sun in order to undergo this type of collapse.[3] The star that resulted in this supernova was estimated to be in the range of 20 solar masses.[1]
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