The Scale of the Universe

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The Scale of the Universe From our Solar System to the edges of the observable universe Our Solar System Our Average distance from the Earth: Average distance from the Sun: Moon - 240,000 miles Jupiter - 483.3 million miles Sun - 93,000,000 miles (93 million) Pluto - 3,666,000,000 miles (3.6 billion miles) Our Galaxy - The Milky Way Distance from the Sun to the nearest star (Proxima Centauri) 25,606,000,000,000 miles (25.6 trillion miles) OR 4.34 light-years 1 light-year = the distance light travels in one year The Milky Way Galaxy is 100,000 light-years in diameter! The Local Group of Galaxies The Milky Way has a number of smaller satellite galaxies orbiting it. The largest one is 170,000 ly away from Earth. Large Magellanic Cloud Small Magellanic Cloud The Local Group of Galaxies The Milky Way and Andromeda galaxies are the largest in the local group The Local Group of Galaxies Andromeda Galaxy Local Group: about 30 galaxies; 10 million ly in diameter Virgo Supercluster of Galaxies The local group is one of many galaxy groups within our supercluster Virgo Supercluster: hundreds of galaxies; over 100 million ly in diameter The Rest of the Observable Universe The universe contains millions of galactic superclusters! Image Descriptions • Slide 2; model of the Solar System • 3; model of the Milky Way Galaxy with the Sun’s position labeled • 4; Large and Small Magellanic Clouds (satellite galaxies of the Milky Way) • 5; model showing distance between the Milky Way and Andromeda galaxies • 6; Andromeda Galaxy (in the constellation Andromeda) • 7; Virgo Supercluster (in the constellation Virgo) • 8; Hubble Deep Field (one of the most distant images ever taken where every bit of light represents an entire galaxy).

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Metallicity Relation in the Magellanic Clouds Clusters,,
A&A 554, A16 (2013) Astronomy DOI: 10.1051/0004-6361/201220926 & c ESO 2013 Astrophysics Age – metallicity relation in the Magellanic Clouds clusters,, E. Livanou1, A. Dapergolas2,M.Kontizas1,B.Nordström3, E. Kontizas2,J.Andersen3,5, B. Dirsch4, and A. Karampelas1 1 Section of Astrophysics Astronomy & Mechanics, Department of Physics, University of Athens, 15783 Athens, Greece e-mail: [email protected] 2 Institute of Astronomy and Astrophysics, National Observatory of Athens, PO Box 20048, 11810 Athens, Greece 3 Niels Bohr Institute Copenhagen University, Astronomical Observatory, Juliane Maries Vej 30, 2100 Copenhagen, Denmark 4 Facultad de Ciencias Astronomicas y Geoﬁsicas, Universidad Nacional de La Plata, B1900 FWA La Plata Buenos Aires, Argentina 5 Nordic Optical Telescope, Apartado 474, 38700 Santa Cruz de La Palma, Spain Received 14 December 2012 / Accepted 2 March 2013 ABSTRACT Aims. We study small open star clusters, using Strömgren photometry to investigate a possible dependence between age and metallicity in the Magellanic Clouds (MCs). Our goals are to trace evidence of an age metallicity relation (AMR) and correlate it with the mutual interactions of the two MCs and to correlate the AMR with the spatial distribution of the clusters. In the Large Magellanic Cloud (LMC), the majority of the selected clusters are young (up to 1 Gyr), and we search for an AMR at this epoch, which has not been much studied. Methods. We report results for 15 LMC and 8 Small Magellanic Cloud (SMC) clusters, scattered all over the area of these galaxies, to cover a wide spatial distribution and metallicity range. The selected LMC clusters were observed with the 1.54 m Danish Telescope in Chile, using the Danish Faint Object Spectrograph and Camera (DFOSC) with a single 2k × 2k CCD.
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Unusual Orbits in the Andromeda Galaxy Post-16
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Messier Objects
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Introduction to Astronomy from Darkness to Blazing Glory
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Elements of Astronomy and Cosmology Outline 1
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Astronomy 422
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The Milky Way Almost Every Star We Can See in the Night Sky Belongs to Our Galaxy, the Milky Way
The Milky Way Almost every star we can see in the night sky belongs to our galaxy, the Milky Way. The Galaxy acquired this unusual name from the Romans who referred to the hazy band that stretches across the sky as the via lactia, or “milky road”. This name has stuck across many languages, such as French (voie lactee) and spanish (via lactea). Note that we use a capital G for Galaxy if we are talking about the Milky Way The Structure of the Milky Way The Milky Way appears as a light fuzzy band across the night sky, but we also see individual stars scattered in all directions. This gives us a clue to the shape of the galaxy. The Milky Way is a typical spiral or disk galaxy. It consists of a flattened disk, a central bulge and a diffuse halo. The disk consists of spiral arms in which most of the stars are located. Our sun is located in one of the spiral arms approximately two-thirds from the centre of the galaxy (8kpc). There are also globular clusters distributed around the Galaxy. In addition to the stars, the spiral arms contain dust, so that certain directions that we looked are blocked due to high interstellar extinction. This dust means we can only see about 1kpc in the visible. Components in the Milky Way The disk: contains most of the stars (in open clusters and associations) and is formed into spiral arms. The stars in the disk are mostly young. Whilst the majority of these stars are a few solar masses, the hot, young O and B type stars contribute most of the light.
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Facilitator Information – Galaxies
Facilitator Information (All you need to know about galaxies to survive the day) What is a galaxy? Galaxies are large collections of stars and gas and dust. They have millions to billions of stars, all held into a cluster by gravitational attraction. Most galaxies are flat, but there are different shapes — some are spirals, some are elliptical, and some are irregular. Our Galaxy The Milky Way is a galaxy, a slowly rotating cluster of more than 200,000,000,000 stars! Our Milky Way Galaxy looks a little like a pinwheel. It is a spiral galaxy, about 100,000 light years across. Spiral galaxies have: a bulge in the center (called the nuclear bulge) that contains the nucleus; a wide, flat disk with distinct spiral arms containing stars; and a surrounding halo of stars. There are several “spiral arms” in our Milky Way: Sagittarius, Cygnus, Perseus, and Orion. Where are we in the Milky Way Galaxy? We are in one of the spiral arms, about 30,000 light years from the center of the Milky Way Galaxy — or about two-thirds of the way from the center. Can you see the Milky Way? Yes! On a very dark night, away from bright lights, you can see a faint, hazy — or milky — band in the sky. This is the Milky Way. The hazy appearance is because there so many stars that are very distant; your eye cannot distinguish the stars as separate points of light. By using binoculars or a telescope, you can see the individual stars. The Milky Way is like a big, flat disk in space.
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The Andromeda Galaxy's Most Important Merger
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