The intergalactic wanderer (NGC 2419) is actually not wandering. It is in a 3 billion year orbit around the Milky Way, which takes it further away than the Magellanic Clouds. It's currently 275 000 ly from us and 300 000 ly from the milky way's centre. I remember reading some notes in"Cirque du Ciel" (actually Cartes du Ciel) that the individual stars are 17th magnitude. Some facts about it don't square with me. I read that this globular is huge, and compares to omega centari (see recent posts), which has millions of stars. It is intrinsically very bright in total and appears as a 9th magnitude fuzz in the scope. But the individual stars must be 17 or so magnitudes below that (because 17 magnitudes = a factor of 6.3 million in brightness), more like 26th mag. Perhaps there is a huge range of brightnesses and the brightest ones around 17th magnitude. It is a big, big thing a long, long way away in any case! I wonder if it can sense the dark matter halo? The cluster lies in the direction of Lynx, near the twin stars Castor and Pollux from our humble perspective. I did a colour blur on this image and upped the saturation, sharpened a bit to make it all pretty. I suspect the colour went a little bit crazy along the way, but I love those colourful, spiky starbursts.
Thursday, 1 December 2011
The Intergalactic Wanderer
The intergalactic wanderer (NGC 2419) is actually not wandering. It is in a 3 billion year orbit around the Milky Way, which takes it further away than the Magellanic Clouds. It's currently 275 000 ly from us and 300 000 ly from the milky way's centre. I remember reading some notes in"Cirque du Ciel" (actually Cartes du Ciel) that the individual stars are 17th magnitude. Some facts about it don't square with me. I read that this globular is huge, and compares to omega centari (see recent posts), which has millions of stars. It is intrinsically very bright in total and appears as a 9th magnitude fuzz in the scope. But the individual stars must be 17 or so magnitudes below that (because 17 magnitudes = a factor of 6.3 million in brightness), more like 26th mag. Perhaps there is a huge range of brightnesses and the brightest ones around 17th magnitude. It is a big, big thing a long, long way away in any case! I wonder if it can sense the dark matter halo? The cluster lies in the direction of Lynx, near the twin stars Castor and Pollux from our humble perspective. I did a colour blur on this image and upped the saturation, sharpened a bit to make it all pretty. I suspect the colour went a little bit crazy along the way, but I love those colourful, spiky starbursts.
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