wvreeven
February 11th, 2024, 09:01 PM
M 41, NGC 2287, Little Beehive Cluster
Open Cluster
Canis Major
RA: 06 45 59.8
DEC: -20 42 58
Mag: 4.5
Diam: 39.8' x 39.8'
5351
NOIRLab / NSF / AURA - https://noirlab.edu/public/es/images/noao-m41/
This week's OOTW is a bright cluster a few degrees south of Sirius, the brightest star in the night sky. From a dark location, it can be seen naked eye as a round glow right next to the star 12 CMa, which is not part of the cluster. The Greek philosopher and polymath Aristotle may have noticed about 325 B.C. but the discovery of the cluster is accredited to Giovanni Battista Hodierna.
In 1654 he published "De systemate orbis cometici; deque admirandis coeli characteribus" (Of the systematics of the world of comets, and on the admirable objects of the sky) which contained 19 nebulous objects which resembled comets but weren't. From SEDS (http://www.messier.seds.org/xtra/Bios/hodierna.html):
Hodierna's catalog of nebulous objects includes independent rediscoveries of the Andromeda Nebula (M31) and the Orion Nebula (M42) and at least 9, but probably 14 and perhaps 16, own original discoveries: M6, M36, M37, M38, M41, M47, NGC 2362, NGC 6231, the Lagoon Nebula M8, the Alpha Persei Cluster (Mel 20), probably M33, M34 and NGC 752, and (possibly) NGC 2451, as well as two further possible discoveries of NGC 2169 and NGC 2175 for which the identification is very unsafe. Also in this work, he created the first preserved drawing of the Orion Nebula.
In other words, he beat Messier by 120 years! The work, however, fell forgotten and wasn't recovered until 1985.
Physically, M 41 contains about 100 stars including several red giants and white dwarfs. It is estimated to be about 190 million years old and lies at some 2300 lightyears from Earth. At a mere 240 lightyears the star 12 CMa is a foreground star and doesn't form part of the cluster.
Over the past 35 years I have observed M 41 many times with the naked eye, binoculars and small to large telescopes. Last night I observed it when it was near zenith from the Rio Hurtado Valley in Chile. At 83x the color difference between 5 red giants and the other, blueish white stars was striking. According to WDS there are 11 double stars in the cluster. I didn't actively track those down and only noticed HJ 2341 as a reddish star and a blueish star while both in fact are blueish. Go figure.
As always,
"Give it a go and let us know!
Good luck and great viewing!"
Open Cluster
Canis Major
RA: 06 45 59.8
DEC: -20 42 58
Mag: 4.5
Diam: 39.8' x 39.8'
5351
NOIRLab / NSF / AURA - https://noirlab.edu/public/es/images/noao-m41/
This week's OOTW is a bright cluster a few degrees south of Sirius, the brightest star in the night sky. From a dark location, it can be seen naked eye as a round glow right next to the star 12 CMa, which is not part of the cluster. The Greek philosopher and polymath Aristotle may have noticed about 325 B.C. but the discovery of the cluster is accredited to Giovanni Battista Hodierna.
In 1654 he published "De systemate orbis cometici; deque admirandis coeli characteribus" (Of the systematics of the world of comets, and on the admirable objects of the sky) which contained 19 nebulous objects which resembled comets but weren't. From SEDS (http://www.messier.seds.org/xtra/Bios/hodierna.html):
Hodierna's catalog of nebulous objects includes independent rediscoveries of the Andromeda Nebula (M31) and the Orion Nebula (M42) and at least 9, but probably 14 and perhaps 16, own original discoveries: M6, M36, M37, M38, M41, M47, NGC 2362, NGC 6231, the Lagoon Nebula M8, the Alpha Persei Cluster (Mel 20), probably M33, M34 and NGC 752, and (possibly) NGC 2451, as well as two further possible discoveries of NGC 2169 and NGC 2175 for which the identification is very unsafe. Also in this work, he created the first preserved drawing of the Orion Nebula.
In other words, he beat Messier by 120 years! The work, however, fell forgotten and wasn't recovered until 1985.
Physically, M 41 contains about 100 stars including several red giants and white dwarfs. It is estimated to be about 190 million years old and lies at some 2300 lightyears from Earth. At a mere 240 lightyears the star 12 CMa is a foreground star and doesn't form part of the cluster.
Over the past 35 years I have observed M 41 many times with the naked eye, binoculars and small to large telescopes. Last night I observed it when it was near zenith from the Rio Hurtado Valley in Chile. At 83x the color difference between 5 red giants and the other, blueish white stars was striking. According to WDS there are 11 double stars in the cluster. I didn't actively track those down and only noticed HJ 2341 as a reddish star and a blueish star while both in fact are blueish. Go figure.
As always,
"Give it a go and let us know!
Good luck and great viewing!"