Subj : Daily APOD Report To : All From : Ben Ritchey Date : Sun Jan 13 2019 05:52:29 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 January 13 [2] Tycho's Supernova Remnant in X-ray Image Credit: NASA [3] / CXC [4] / F.J. Lu (Chinese Academy of Sciences) et al. [5] Explanation: What star created this huge puffball? What's pictured is the hot expanding nebula of Tycho's supernova remnant [6] , the result of a stellar explosion first recorded over 400 years ago by the famous astronomer Tycho Brahe [7] . The featured image [8] is a composite of three X-ray [9] colors taken by the orbiting Chandra X-ray Observatory [10] . The expanding gas cloud [11] is extremely hot, while slightly different expansion speeds have given the cloud a puffy [12] appearance. Although the star that created SN 1572 [13] , is likely completely gone, a star dubbed Tycho G [14] , too dim to be discerned here [15] , is thought to be a companion. Finding progenitor remnants of Tycho's supernova [16] is particularly important because the supernova [17] is of Type Ia, an important rung in the distance ladder [18] that calibrates the scale [19] of the visible universe. The peak brightness of Type Ia supernovas [20] is thought to be well understood, making them quite valuable in exploring the relationship between faintness and farness [21] in the distant universe. Tomorrow's picture: meteor mountain ------------------------------------------------------------------------------- < [22] | Archive [23] | Submissions [24] | Index [25] | Search [26] | Calendar [27] | RSS [28] | Education [29] | About APOD [30] | Discuss [31] | > [32] ------------------------------------------------------------------------------- Authors & editors: Robert Nemiroff [33] (MTU [34] ) & Jerry Bonnell [35] (UMCP [36] ) NASA Official: Phillip Newman Specific rights apply [37] . NASA Web Privacy Policy and Important Notices [38] A service of: ASD [39] at NASA [40] / GSFC [41] & Michigan Tech. U. [42] ---------- Site notes: [1] archivepix.html [2] image/1901/TychoSNR_Chandra_3600.jpg [3] http://www.nasa.gov/ [4] http://chandra.harvard.edu/ [5] http://arxiv.org/abs/1102.3829 [6] https://en.wikipedia.org/wiki/Tycho%27s_Supernova [7] http://galileo.rice.edu/sci/brahe.html [8] http://chandra.harvard.edu/photo/2011/tycho2/ [9] https://science.nasa.gov/ems/11_xrays [10] http://chandra.harvard.edu/about/ [11] http://chandra.si.edu/photo/2016/tycho/tycho_BU_lg_web.mov [12] https://www.youtube.com/watch?v=Zr_DwYHaxx4 [13] http://spider.seds.org/spider/Vars/sn1572.html [14] https://en.wikipedia.org/wiki/Tycho_G [15] https://arxiv.org/abs/1604.01779 [16] http://www.solstation.com/x-objects/tycho-s.htm [17] http://www.youtube.com/watch?v=sTyMffjKTTo [18] https://en.wikipedia.org/wiki/Cosmic_distance_ladder [19] ap181007.html [20] http://en.wikipedia.org/wiki/Type_Ia_supernova [21] http://www-supernova.lbl.gov/PhysicsTodayArticle.pdf [22] ap190112.html [23] archivepix.html [24] lib/apsubmit2015.html [25] lib/aptree.html [26] https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search [27] calendar/allyears.html [28] /apod.rss [29] lib/edlinks.html [30] lib/about_apod.html [31] http://asterisk.apod.com/discuss_apod.php?date=190113 [32] ap190114.html [33] http://www.phy.mtu.edu/faculty/Nemiroff.html [34] http://www.phy.mtu.edu/ [35] https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html [36] http://www.astro.umd.edu/ [37] lib/about_apod.html#srapply [38] https://www.nasa.gov/about/highlights/HP_Privacy.html [39] https://astrophysics.gsfc.nasa.gov/ [40] https://www.nasa.gov/ [41] https://www.nasa.gov/centers/goddard/ [42] http://www.mtu.edu/ --- Mystic BBS v1.12 A42 (Windows/32) * Origin: FIDONet - The Positronium Repository (1:393/68) .