MickStonedAgain
Great Hercules Cluster (NGC 6205)
Photo by: MickS.2017
Observation date: Monday, October 30, 2017
Observation time: 19:20 UTC
Observatory: Slooh Canary Islands
Telescope: Canary One
Instrument: Canary Half Meter
Messier 13 contains several hundred thousand stars; some sources even quote more than a million. The brightest is the variable star V11, with an apparent magnitude of 11.95. Toward the center of M 13, stars are about 500 times more concentrated than in the solar neighborhood. While the probability of collisions between stars in such a crowded region is negligible, the night sky seen from a planet near the center of of this globular cluster would be filled with thousands of stars brighter than Venus and Sirius!
Unlike open clusters, such as the Pleiades, globular clusters are tightly bound together by gravity, and contain very old, mostly red stars. The age of M 13 has revised to 12 billion years - nearly as old as the Milky Way galaxy itself. Born before the Galaxy's stars had a chance to create metals and distribute them them in its star-forming regions, M 13's iron content relative to hydrogen is just 5% of the Sun's.
Great Hercules Cluster (NGC 6205)
Photo by: MickS.2017
Observation date: Monday, October 30, 2017
Observation time: 19:20 UTC
Observatory: Slooh Canary Islands
Telescope: Canary One
Instrument: Canary Half Meter
Messier 13 contains several hundred thousand stars; some sources even quote more than a million. The brightest is the variable star V11, with an apparent magnitude of 11.95. Toward the center of M 13, stars are about 500 times more concentrated than in the solar neighborhood. While the probability of collisions between stars in such a crowded region is negligible, the night sky seen from a planet near the center of of this globular cluster would be filled with thousands of stars brighter than Venus and Sirius!
Unlike open clusters, such as the Pleiades, globular clusters are tightly bound together by gravity, and contain very old, mostly red stars. The age of M 13 has revised to 12 billion years - nearly as old as the Milky Way galaxy itself. Born before the Galaxy's stars had a chance to create metals and distribute them them in its star-forming regions, M 13's iron content relative to hydrogen is just 5% of the Sun's.