10A Galaxies Island Universes

10A Copyright – Adam Block, KPNO

10A Hubble Tuning Fork

10A Ellipticals

10A Huge No gas. No dust. No young stars. Nothing but old stars. –Random orbits.

10A M 87 Copyright – Anglo-Australian Telescope Board Copyright - HST

10A Hubble Tuning Fork

10A Copyright – Adam Block, KPNO

10A Spirals

10A Like Milky Way Disks and bulge. Young stars and old. Gas and dust. Stars forming. Stars dying. M81 and M82 – Copyright R. Gendler

10A M63 Copyright – S. Miyazaki, Suburu

10A NGC1365 Copyright – VLT

10A M31 The Andromeda Galaxy Copyright – Jason Ware Copyright – S. Miyazaki, Suburu

10A M33 – Copyright NOAO

10A M51 - Copyright HST John P. Gleason

10A NGC 4314

10A NGC 891 – Copyright J.C. Barentine, NOAO NGC 891 – Copyright WIYN

10A Sombrero Galaxy – Copyright P. Barthel VLT M10 – copyright Credner and Kohle

10A NGC 4526

10A Irregulars

10A Groups

10A The Local Group

10A Clusters

10A

10A NGC 1316 – Copyright VLT

10A The Virgo Cluster

10A The Hubble Deep Field

10A 21cm Radiation Neutral hydrogen (HI) gives off radiation at 21cm. Milky Way HI emission – Copyright J. Dickey

10A Extragalactic HI Observe HI in other galaxies.

10A Rotation Curves If HI gas is rotating or moving, the 21cm radiation will be Doppler Shifted.

10A

10A

10A Galaxy Masses Apply Kepler’s Laws to galaxy pairs. Get estimates of mass. Result: more dark matter. Apply Kepler’s Laws to galaxy clusters. Get mass estimates. Result: even more dark matter!

10A

10A Hubble’s Law Measure the velocity of every galaxy. Nearly all are redshifted. Use Cepheids to measure distances to nearby galaxies. Result: The faster it’s moving, the farther away it is.

10A Map the Universe Measure v Calculate d Find: Voids Walls Clusters