DM Geminorum
Encyclopedia
DM Geminorum or Nova Geminorum 1903 was a nova
which appeared in 1903 in the constellation Gemini
and reached a brightness of 4.8 mag
. Its brightness decreased in 17 days by 3 mag. Today it is only of 16.5 mag.
It was discovered by Herbert Hall Turner
.
Nova
A nova is a cataclysmic nuclear explosion in a star caused by the accretion of hydrogen on to the surface of a white dwarf star, which ignites and starts nuclear fusion in a runaway manner...
which appeared in 1903 in the constellation Gemini
Gemini (constellation)
Gemini is one of the constellations of the zodiac. It was one of the 48 constellations described by the 2nd century astronomer Ptolemy and it remains one of the 88 modern constellations today. Its name is Latin for "twins", and it is associated with the twins Castor and Pollux in Greek mythology...
and reached a brightness of 4.8 mag
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
. Its brightness decreased in 17 days by 3 mag. Today it is only of 16.5 mag.
It was discovered by Herbert Hall Turner
Herbert Hall Turner
Herbert Hall Turner was a British astronomer and seismologist.-Biography:Herbert Hall Turner was educated at Clifton College and Trinity College, Cambridge., In 1884 he accepted the post of Chief Assistant at Greenwich Observatory and stayed there for nine years...
.