Imagine the Universe!
Imagine Home  |   Ask an Astrophysicist  |  
Ask an Astrophysicist

The Question

(Submitted November 24, 1997)

Who was the first person to discover a black hole and what was the date?

The Answer

Black holes cannot be observed directly and therefore cannot be 'discovered'.

However, as we explain at our website, the indirect evidence for two kinds of black hole is now overwhelming - those of a few solar masses produced by supernovae and much larger ones at the center of some galaxies.

The existence of bodies with gravitational fields strong enough to allow nothing to escape has been a topic of speculation for hundreds of years. Einstein's general theory of relativity (published in 1916) predicts just the kinds of object we are now inferring.

Perhaps the first object to be generally recognized as a black hole is the X-ray binary star Cygnus X-1. Its effect on its companion star suggested as early as 1971 that it must be a compact object with a mass too high for it to be a neutron star. (That was 2 years after the American astronomer John Wheeler coined the term 'black hole').

Paul Butterworth
for the Ask an Astrophysicist Team

Previous question
Main topic
Next question

Imagine the Universe is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center.

The Imagine Team
Acting Project Leader: Dr. Barbara Mattson
All material on this site has been created and updated between 1997-2012.

DVD Table of Contents
Educator's Index