The Great Attractor is far bigger than a galaxy. In the terminology of astronomers, these are clusters of galaxies containing maybe hundreds of galaxies, and superclusters containing many clusters.
The Norma Cluster is the closest massive galaxy cluster to the Milky Way, and lies about 220 million light-years away. The enormous mass concentrated here, and the consequent gravitational attraction, mean that this region of space is known to astronomers as the Great Attractor, and it dominates our region of the Universe.
Our galaxy, along with other galaxies in our local group, is currently rushing at a speed of nearly 1,000km per second towards the Great Attractor which is about 220 million light years away from us.
This Great Attractor has a mass of nearly 100 quadrillion times greater than our sun and span of 500 million light-years, and is made of both the visible matter and dark matter.
So in a way its a massive black hole which is pulling us.
This motion can only be accounted for by gravitational attraction, even though the mass that we can observe is not nearly great enough to exert that kind of pull. The only thing that could explain the movement of Andromeda is the gravitational pull of a lot of unseen mass--perhaps the equivalent of 10 Milky Way-size galaxies--lying between the two galaxies.
Meanwhile, our entire Local Group is hurtling toward the center of the Virgo cluster at one million miles per hour.
If you want to know more about The Great Attractor and the theories behind it click here:
http://www.dailygalaxy.com/my_weblog/2009/03/mystery-of-the.html
The Norma Cluster is the closest massive galaxy cluster to the Milky Way, and lies about 220 million light-years away. The enormous mass concentrated here, and the consequent gravitational attraction, mean that this region of space is known to astronomers as the Great Attractor, and it dominates our region of the Universe.
Our galaxy, along with other galaxies in our local group, is currently rushing at a speed of nearly 1,000km per second towards the Great Attractor which is about 220 million light years away from us.
This Great Attractor has a mass of nearly 100 quadrillion times greater than our sun and span of 500 million light-years, and is made of both the visible matter and dark matter.
So in a way its a massive black hole which is pulling us.
This motion can only be accounted for by gravitational attraction, even though the mass that we can observe is not nearly great enough to exert that kind of pull. The only thing that could explain the movement of Andromeda is the gravitational pull of a lot of unseen mass--perhaps the equivalent of 10 Milky Way-size galaxies--lying between the two galaxies.
Meanwhile, our entire Local Group is hurtling toward the center of the Virgo cluster at one million miles per hour.
If you want to know more about The Great Attractor and the theories behind it click here:
http://www.dailygalaxy.com/my_weblog/2009/03/mystery-of-the.html
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