Galaxy Group and Cluster Astronomy at RIT

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Galaxy Group and Cluster Astronomy at RIT Galaxy Group and Cluster Astronomy at RIT 23 Spitzer,)HST,)GALEX,)&)Chandra)Image) Green Bank 100M Hershel 3.5M Credit:)NRAO) Credit:)Chicago)University) Hubble Space Telescope (HST) Sloan Digital 2.4M Sky Survey 2.5M Credit:) Hubblesite ) In Space On Earth Astronomers at RIT want to learn about galaxy groups and clusters. They use a variety of ground- and space-based telescopes. 24 YOU ARE HERE Milky Way galaxy Artist’s representation Here’s where the sun lives! We are on the outskirts of the Milky Way. It takes the sun 200 million years to travel once around the galaxy. Credit:)NASA/JPLJCaltech/R) 25 Sometimes galaxies run past each other or even combine! ZOOM Antennae Galaxies This can jumpstart star formation and make irregularly shaped galaxies like the ones shown here. 26 Credit:)HubbleSite) Living as a group of galaxies, the Milky Way has neighbors: the larger Andromeda and the smaller Tr i a n g u l u m . The Milky Way s Home The Local Group Andromeda Galaxy This is an artist’s interpretation. NGC185 Not drawn to scale. NGC147 M32 Tr i a n g u l u m Galaxy NGC205 Pegasus Milky Way Galaxy IC1613 Draco Fornax WLM Ursa Minor Sculptor LEo I Leo II Sextans NGC6822 SMC LMC Carina Artist’s representation of the Local Group Around each larger galaxy there are dozens of dwarf galaxies. It takes light 2.5 million years to get to Earth from Andromeda. 27 Hundreds, or even thousands, of galaxies can live together in a cluster. A crowded neighborhood Abell 1689 shown here has over 2000 galaxies living far, far away from Earth. Collisions can happen more often when it’s crowded! ) Credit:)HubbleSite 28 Simulated here is a block of the universe 360 The Universe million light years across. Each zoom in shows the galaxies living in clusters and from afar groups in a giant web dominated by the mysterious “dark matter*”! A light year is the distance it takes light to travel in one year—nearly 6 trillion miles! Zoomed out ‘Cosmic Web’ Cluster 360 million Light years Single galaxy Credit:)BoylanJKolchin)et)al.)(2009)) 29 .
Recommended publications
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