Posted on 06/30/2018 4:56:13 PM PDT by Simon Green
(much larger hi-res picture at link)
Globular clusters are gravitationally-bound groupings of stars which orbit galaxies.
These objects typically contain hundreds of thousands of stars that are thought to have formed at roughly the same time as their host galaxy.
They are denser and more spherical than open star clusters like the famous Pleiades.
The large mass in the rich stellar center of the cluster pulls the stars inward to form a ball of stars. The word globulus, from which these clusters take their name, is Latin for small sphere.
It is thought that every galaxy has a population of globular clusters. Some galaxies have a few hundred, while giant ellipticals can have several thousand.
Our Milky Way Galaxy is orbited by at least 150 globular clusters, including NGC 6139.
First discovered in May 1826 by Scottish astronomer James Dunlop, NGC 6139 is some 35,000 light-years distant.
The cluster is seen roughly in the direction of the center of the Milky Way, in the constellation of Scorpius.
Most globular clusters are estimated to be over 10 billion years old.
As a result they contain some of the oldest stars in the Milky Way, formed very early in its history. However, their role in galactic evolution is still a matter of study.
This image of NGC 6139 is a composite of separate exposures acquired by Hubbles Wide-Field Camera 3 (WFC3) instrument.
Two filters a blue (F438W) filter and a wide-band (F555W) filter were used to sample various wavelengths.
The color results from assigning different hues to each monochromatic image associated with an individual filter.
(Excerpt) Read more at sci-news.com ...
What a cluster-coitus.
cluster-ping
God is ETERNAL!! Of course there are BILIONS and BILIONS of stars and PLANETS!!!!
M13/NGC 6205. 40x25s
Michael Moore
That’s a really good picture, Dragnet2 - thank you for sharing it with us!
It's not bad, but truth is the image suffers from what is called vignetting. Looking closer at the corners, they're darker than the rest of the image. This was due to issues in the optical train in front of the camera.
One day soon I plan or revisiting this star cluster which is just outside of our galaxy, to see if I can correct it. If not it'll still be fun to get away from this planet for a while anyway.☺
I figured someone would have beat me to it.
I got your globular cluster, right here.
Beautiful!
TX!
“about 22,200 light-years away from Earth”
Awesome pic, thanks for posting. RE the distance, I can’t even comprehend 1 light year, let alone more than 22,000 light years.
Indeed a good shot!
Next time you do astro-pho, go for M22, M3, M5 or M92
All great globulars.
Nice!
So globular clusters are OUTSIDE their host galaxy and actually “orbit” the galaxy? That is an unimaginably large orbit. I wonder what the orbital period is.
How tightly packed are the stars in globular clusters? Are they close together (astronomically speaking)?
Could you tell us about your telescope and camera? It is a fantastic shot.
Rosie Odonell
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