Johann Gottfried Galle
Johann Gottfried Galle (
June 9,
1812 in
Radis,
Saxony-Anhalt –
July 10,
1910 in
Potsdam,
Brandenburg) was a German
astronomer at the
Berlin Observatory who, with the assistance of student
Heinrich Louis d'Arrest, was the first person to view the planet
Neptune, and know what he was looking at (
September 23,
1846). He used the calculations of
Urbain Le Verrier to know where to look.
He had started to work as an assistant to
Johann Franz Encke in
1835 immediately following the completion of the Berlin observatory. In
1851 he moved to Breslau (now
Wrocław) to become professor of astronomy and the director of the local observatory.
Throughout his career he studied
comets, and in
1894 (with the help of his son
Andreas Galle) he published a list with 414 comets. He himself had previously discovered three comets in the short span from
December 2,
1839 to
March 6,
1840.
Craters on the
Moon and
Mars, and a
ring of Neptune, were named in his honor.
Galle's Ph.D. thesis finished in
1845 was a reduction and critical discussion of
Ole Rømer's observation of
meridian transits of
stars and
planets on the days from
October 20 to
October 23,
1706. Around
1845 he sent a copy of his thesis to Urbain Le Verrier, but only received an answer a year later on
September 18,
1846. It reached Galle on
September 23 and in it Le Verrier asked him to look at a certain region of sky to find a predicted new planet, which would explain the perturbations of Uranus. The same night, after Encke gave him the permission against his own judgement, an object fitting the description was found, and it was confirmed as being a planet over the next two evenings.
Obituaries
*
AN 185 (1910) 309/310 (in German)
*
JRASC 4 (1910) 379*
MNRAS 71 (1911) 275*
Obs 33 (1910) 314 (not online)
