SN 1979C

{{Short description|Supernova event of 1979 in the constellation Coma Berenices.}}

{{Supernova

| name = SN 1979C

| image = 300px

| epoch = J2000.0

| type = Type II{{cite web|title=Has a Recent, Nearby Supernova Become a Baby Black Hole?|url=http://www.universetoday.com/78836/has-a-recent-nearby-supernova-become-a-baby-black-hole/|author=Nancy Atkinson|date=November 15, 2010|publisher=Universe Today|accessdate=2010-11-18}}

| SNRtype = ?

| host = M100

| constellation = Coma Berenices

| ra = 12^h 22^m 58.58^s

| dec = +15° 47{{prime}} 52.7{{pprime}}

| gal = G271.2454 +76.8848

| discovery = 1979

| iauc =

| mag_v = +12.23

| distance = 50 Mly

| progenitor = ?

| progenitor_type = ?

| b-v = ?

| notes =

}}

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.{{cite web|title=The Man Who Discovered SN 1979C and Beat the Machines|url=http://chandra.harvard.edu/chronicle/0410/sn1979c/index.html|publisher=Center for Astrophysics {{!}} Harvard & Smithsonian|author=Peter Edmonds|date=November 16, 2010|accessdate=2010-11-21}} 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.{{cite journal| last = Gilmore | first = Gerry| title=The Short Spectacular Life of a Superstar| journal=Science | date=2004 | volume=304| issue=5697 | pages=1915–1916 | url=http://www.sciencemag.org/cgi/content/full/sci;304/5679/1915| accessdate=2007-05-01 | doi=10.1126/science.1100370| pmid = 15218132 | s2cid = 116987470| url-access=subscription }} The star that resulted in this supernova was estimated to be in the range of 20 solar masses.

On November 15, 2010 NASA announced that evidence of a black hole had been detected as a remnant of the supernova explosion. Scientists led by Dr. Dan Patnaude from the Center for Astrophysics {{!}} Harvard & Smithsonian in Cambridge, MA evaluated data gathered between 1995 and 2007 from several 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.{{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|author2=Janet Anderson|author3=Megan Watzke|archive-date=2016-03-03|archive-url=https://web.archive.org/web/20160303211944/http://www.nasa.gov/home/hqnews/2010/nov/HQ_10-299_CHANDRA.html|url-status=dead}}

The researchers observed a steady source of X-rays and determined that it was likely that this was material being fed into the object either from the supernova or a 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. 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.{{cite journal

|last1=Weiler|first1=K. W.

|last2=van Dyk|first2=S. D.

|last3=Discenna|first3=J. L.

|last4=Panagia|first4=N.

|last5=Sramek|first5=R. A.

|date=1991 |title=The 10 year radio light curves for SN 1979C |journal=Astrophysical Journal|volume= 380|pages=161–166 |bibcode=1991ApJ...380..161W |doi = 10.1086/170571 |doi-access=free}}