Image: Hubble stares into the crammed center of Messier 22

April 13, 2015
Credit: ESA/Hubble and NASA

This image shows the center of the globular cluster Messier 22, also known as M22, as observed by the NASA/ESA Hubble Space Telescope. Globular clusters are spherical collections of densely packed stars, relics of the early years of the Universe, with ages of typically 12 to 13 billion years. This is very old considering that the Universe is only 13.8 billion years old.

Messier 22 is one of about 150 in the Milky Way and at just 10,000 light-years away it is also one of the closest to Earth. It was discovered in 1665 by Abraham Ihle, making it one of the first globulars ever to be discovered. This is not so surprising as it is one of the brightest globular clusters visible from the , located in the constellation of Sagittarius, close to the Galactic Bulge—the dense mass of stars at the center of the Milky Way.

The cluster has a diameter of about 70 light-years and, when looking from Earth, appears to take up a patch of sky the size of the full Moon. Despite its relative proximity to us, the light from the stars in the cluster is not as bright as it should be as it is dimmed by dust and gas located between us and the cluster.

As they are leftovers from the early Universe, globular clusters are popular study objects for astronomers. M22 in particular has fascinating additional features: six planet-sized objects that are not orbiting a star have been detected in the cluster, it seems to host two , and the cluster is one of only three ever found to host a planetary nebula—a short-lived gaseous shells ejected by massive stars at the ends of their lives.

Explore further: Image: Hubble sees an ancient globular cluster

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Mr Som-o
not rated yet Apr 14, 2015
It would be interesting to know how close some of the stars in M22 are to each other.
antialias_physorg
not rated yet Apr 14, 2015
It would be interesting to know how close some of the stars in M22 are to each other.

The closest ones will be as close as anywhere else (binary star systems)

But for an average density:
Wikipedia claims roughly 70k stars in M22 (and 2 known black holes with an estimated 5-100 still unobserved). At 70 LY diameter that gives you - very roughly - 2.5 stars per cubic light year.
(With the binaries the distance distribution will be heavily skewed towards the low end)


vidyunmaya
not rated yet Apr 14, 2015
Sub: Vortex Process near Milky-way
I look at the Milky way - under Plasma Regulated Electromagnetic Phenomena in magnetic Field Environment. The Fields change orientation -between 2700 LY to 12,000LY - and need to stabilize for DMVT Process-this is the Dynamic Function under Cosmic Pot Energy of the Universe
OM COSMIC CONSCIOUSNESS TO COSMOLOGY REVISION-2000( TXU 982-559) Pages 94, Fig 16
SEARCH BEYOND DARK MATTER-COSMOS YOGA SERIES-I 10^3 LY-Tamasoma Jyothirgamyam TXU 1-282-571(June 2005),Books by Vidyardhi nanduri
Your Information: Messier 22 is one of about 150 globular clusters in the Milky Way and at just 10,000 light-years away it is also one of the closest to Earth.The cluster has a diameter of about 70 light-years and, when looking from Earth

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