Astronomers using NASA's Chandra X-ray Observatory have found evidence of the youngest black hole known to exist in our cosmic neighborhood...The 30-year-old object is a remnant of SN 1979C, a supernova in the galaxy M100 approximately 50 million light-years from Earth..."If our interpretation is correct, this is the nearest example where the birth of a black hole has been observed," said Daniel Patnaude of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. who led the study...The scientists think SN 1979C, first discovered by an amateur astronomer in 1979, formed when a star about 20 times more massive than the Sun collapsed.

via Chandra Press Room :: NASA's Chandra Finds Youngest Nearby Black Hole