May 1, 1978, the Astrophysical Journal reported that M87 appeared to have a central mass concentration which could be interpreted as that of a massive black hole.
Iowa Science Teachers Journal
© Copyright 1979 by the Iowa Academy of Science
"New Astronomical Discoveries,"
Iowa Science Teachers Journal: Vol. 16
, Article 18.
Available at: https://scholarworks.uni.edu/istj/vol16/iss1/18