Adiel Ruiz Jaimie Yung Ashley Bumatay Enrique Acosta-Montes Classifying Galaxies • What is it? – Recognizing, naming and describing different groups • Why? – To show similarities and.
Download ReportTranscript Adiel Ruiz Jaimie Yung Ashley Bumatay Enrique Acosta-Montes Classifying Galaxies • What is it? – Recognizing, naming and describing different groups • Why? – To show similarities and.
Adiel Ruiz Jaimie Yung Ashley Bumatay Enrique Acosta-Montes Classifying Galaxies • What is it? – Recognizing, naming and describing different groups • Why? – To show similarities and differences • How? – Look at physical characteristics (center, shape, color, etc) Our Classification System Disk Shaped/ Side View Dense Centers With Fuzziness Spirals Normal Weird CD/Orb Irregular The Milky Way • Spiral Galaxy • Age of the Milky Way: 13.6 billion years • Diameter: 100,000 light years http://antwrp.gsfc.nasa.gov/apod/ap051004.html Our Place in the Milky Way • We don’t know how the Milky Way really looks. stardate.org/images/gallery/sun_mw.gif http://ipac.jpl.nasa.gov/media_images/sig05-010_medium.jpg Galaxy Colors • Elliptical Galaxies are red • Spiral arms of Galaxies have some blue and Irregulars have blue. Irregular Galaxy: http://starchild.gsfc.nasa.gov/Images/StarChild/universe_level2/ngc6822.gif Elliptical Galaxy:http://www.astro.princeton.edu/~frei/Gcat_htm/Catalog/CJpeg/n2768.jpg Spiral Galaxy: http://www.rc-astro.com/img/m101_2004-05-18_web.jpg Emission and Absorption Seplo.phys.utk.edu/astr162/lect/light/bohr.html Galaxy Spectra •Dust •Gas QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. •Stars http://outreach.atnf.csiro.au/education/senior/astrophysics/spectra_astro_types.html Elliptical Galaxy Spectrum • Continuum at shorter wavelengths • No emission lines • Absorption lines http://astronomy.nmsu.edu/nicole/teaching/ASTR505/lect ures/lecture26/slide01.html HII Regions • Region of ionized H • Hot stars ionize H • Transition neutral H Ionized H Neutral H Seplo.phys.utk.edu/astr162/lect/light/bohr.html Spiral Galaxy Spectrum Redshift An increase in the wavelength of radiation emitted by a star or galaxy as a result of the Doppler effect. www.astro.ucla.edu/~wright/doppler.html Redshifted galaxy spectra WAVELENGTH cas.sdss.org/dr4/en/sdss/data/images/redshift.gif obs/em - 1 = z Major Mergers • Occur when 2 galaxies of approximately the same mass collide • Usually create an elliptical galaxy http://ifa.hawaii.edu/~barnes/tog2_gifs/seq1.html Minor Mergers • Minor Mergers: Low mass, Higher mass • The galaxy with low mass gives the galaxy with greater mass the spiral shape. Mihos, J.C. & Hernquist, L. 1994, ApJ, 425, L13 Nickel Telescope • Used the Nickel Telescope to acquire my galaxy image. • Used filters BVR M51: The Whirlpool Galaxy • M51 (NGC 5194) • Classified as a Spiral Galaxy • 31 million lightyears • Satellite Galaxy NGC 5195 Seyfert Galaxies QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. http://almu.astronet.pl/wiedza/kwazary/NGC_4258_WiZ.jpg • Active spiral/irregular galaxies • Center • Emission : x-ray, radio, infrared, ultraviolet M106 (NGC 4258) • Pierre Méchain 1781 • 21-25 million ly • ~30 thousand ly across • BH 36 million x Msun • BH in MW = 2.6 million x Msun M102 • In the constellation Draco • Disk shaped • 45 million light years away • Taken with the Nickel 40” Telescope Lick Observatory 7/20/06 Using Filters: B, V, & R M101 (NGC 5457) • Discovered by Pierre Mechain on March 27, 1781 • Diameter: 170,000 light years • 27 million light years from Earth • Located in Ursa Major Summary • Observations • Classification • Galaxy Colors/ Spectra