Subj : Daily APOD Report To : All From : Ben Ritchey Date : Sun Feb 24 2019 18:11:44 Astronomy Picture of the Day Astronomy Picture of the Day Discover the cosmos! [1] Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2019 February 24 The Expanding Echoes of Supernova 1987A Video Credit & Copyright: David Malin [2] , AAT [3] Explanation: Can you find supernova 1987A? It isn't hard -- it occurred at the center of the expanding bullseye pattern [4] . Although this stellar detonation was first seen in 1987, light from SN 1987A [5] continued to bounce off clumps of interstellar dust [6] and be reflected to us even many years later. Light echoes [7] recorded between 1988 and 1992 by the Anglo Australian Telescope [8] (AAT) in Australia [9] are shown moving out from the position of the supernova in the featured time-lapse sequence. These images were composed by subtracting an LMC image taken before the supernova [10] light arrived from later LMC images that included the supernova echo. Other prominent light echo [11] sequences include those taken by the EROS2 [12] and SuperMACHO [13] sky monitoring projects. Studies [14] of expanding light echo [15] rings around other supernovas have enabled more accurate determinations of the location, date, and symmetry [16] of these tremendous stellar explosions. Yesterday marked the 32nd anniversary of SN 1987A [17] : the last recoded supernova in or around our Milky Way Galaxy [18] , and the last to be visible to the unaided eye. Open Science: Browse 1,800+ codes in the Astrophysics Source Code Library [19] Tomorrow's picture: sky sprite ------------------------------------------------------------------------------- < [20] | Archive [21] | Submissions [22] | Index [23] | Search [24] | Calendar [25] | RSS [26] | Education [27] | About APOD [28] | Discuss [29] | > [30] ------------------------------------------------------------------------------- Authors & editors: Robert Nemiroff [31] (MTU [32] ) & Jerry Bonnell [33] (UMCP [34] ) NASA Official: Phillip Newman Specific rights apply [35] . NASA Web Privacy Policy and Important Notices [36] A service of: ASD [37] at NASA [38] / GSFC [39] & Michigan Tech. U. [40] ---------- Site notes: [1] archivepix.html [2] https://www.davidmalin.com/dfm/general/about_dfm.html [3] https://www.aao.gov.au/about-us/AAT [4] https://en.wikipedia.org/wiki/Bullseye_(target) [5] http://heritage.stsci.edu/1999/04/sn1987anino.html [6] ap030706.html [7] http://www.spitzer.caltech.edu/images/ 2662-ssc2005-14d-Illustration-of-a-Light-Echo [8] https://www.aao.gov.au/about-us/anglo-australian-telescope [9] https://en.wikipedia.org/wiki/Australia [10] https://heasarc.gsfc.nasa.gov/docs/snr.html [11] https://en.wikipedia.org/wiki/Light_echo [12] http://eros.in2p3.fr/EchoesSN1987a/ [13] ap060125.html [14] https://arxiv.org/abs/astro-ph/0510738 [15] https://arxiv.org/abs/1506.02643 [16] http://adsabs.harvard.edu/abs/2013ApJ...767...45S [17] https://en.wikipedia.org/wiki/SN_1987A [18] https://solarsystem.nasa.gov/resources/285/the-milky-way-galaxy/ [19] http://ascl.net/code/all [20] ap190223.html [21] archivepix.html [22] lib/apsubmit2015.html [23] lib/aptree.html [24] https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search [25] calendar/allyears.html [26] /apod.rss [27] lib/edlinks.html [28] lib/about_apod.html [29] http://asterisk.apod.com/discuss_apod.php?date=190224 [30] ap190225.html [31] http://www.phy.mtu.edu/faculty/Nemiroff.html [32] http://www.phy.mtu.edu/ [33] https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html [34] http://www.astro.umd.edu/ [35] lib/about_apod.html#srapply [36] https://www.nasa.gov/about/highlights/HP_Privacy.html [37] https://astrophysics.gsfc.nasa.gov/ [38] https://www.nasa.gov/ [39] https://www.nasa.gov/centers/goddard/ [40] http://www.mtu.edu/ --- Mystic BBS v1.12 A43 (Windows/32) * Origin: FIDONet - The Positronium Repository (1:393/68) .