White hole discovered much earlier

'In astrophysics, a white hole is the time reversal of a black hole. While a black hole acts as an absorber for any matter that crosses the event horizon, a white hole acts as a source that ejects matter from its event horizon. The sign of the acceleration is invariant under time reversal, so both black and white holes attract matter. The only potential difference between them is in the behavior at the horizon.'

Whatever the horizon or the behavior of it? One thing is clear: At least one white hole could have been detected much earlier than in the 20th century if astrophysicists would have gone into Rome Pantheon as pictured above.

Photo from December 2007 looking over the horizon observing the potential difference.