C/1930 L1 (Forbes)
Comet Forbes, formally designated as C/1930 L1, is a parabolic comet that was only observed through optical telescopes in the year 1930.
Observational history
The comet was discovered by Alexander F. I. Forbes as a 9th-magnitude object on the early morning skies of 31 May 1930. It was the fifth new comet of the year and the second of three comets he discovered overall. He immediately informed the Union Observatory in Johannesburg after an exact position was determined about two days later.The comet was already on its outbound flight since it reached perihelion on 10 May 1930, about three weeks before discovery, but was still approaching Earth at the time, allowing it to be regularly observed from Johannesburg until the end of June. It was only visible in the southern hemisphere until 23 June when first northern observations were recorded by the National Observatory in Athens, Greece.
George van Biesbroeck made his first observations of the comet from the Yerkes Observatory on 21 June with Georg von Struve following suit from the Berlin Observatory shortly afterwards, however by that time it rapidly faded away from magnitude 11 to 15 by the end of the month, though a short tail was reported. Van Biesbroeck continued his photographic observations of the comet until 17 July, and its last known position was recorded on 21 July.