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 8
HESS Telescopes Explore the High-Energy Sky
Video Credit & Copyright: Vikas Chander [2] , H.E.S.S. Collaboration [3] ;
Music: Emotive Piano by Immersive Music [4]
Explanation: They may look like modern mechanical dinosaurs but they are
enormous swiveling eyes that watch the sky. The High Energy Stereoscopic
System (H.E.S.S.) Observatory [5] is composed of four 12-meter
reflecting-mirror telescopes surrounding a larger telescope [6] housing a
28-meter mirror. They are designed to detect strange flickers of blue light --
Cherenkov radiation [7] --emitted when charged particles [8] move slightly
faster than the speed of light [9] in air. This light is emitted when a gamma
ray [10] from a distant source strikes a molecule in Earth's atmosphere and
starts a charged-particle shower [11] . H.E.S.S. [12] is sensitive to some of
the highest energy photons (TeV [13] ) crossing the universe. Operating since
2003 in Namibia [14] , H.E.S.S. has searched for dark matter [15] and has
discovered over 50 sources [16] emitting high energy radiation including
supernova remnants [17] and the centers of galaxies [18] that contain
supermassive black holes [19] . Pictured last September, H.E.S.S. telescopes
swivel and stare in time-lapse sequences [20] shot in front of our Milky Way
Galaxy [21] and the Magellanic Clouds [22] -- as the occasional
Earth-orbiting satellite zips by.
Open Science: Browse 1,800+ codes in the Astrophysics Source Code Library [23]
Tomorrow's picture: forgotten stars
-------------------------------------------------------------------------------
< [24] | Archive [25] | Submissions [26] | Index [27] | Search [28] | Calendar
[29] | RSS [30] | Education [31] | About APOD [32] | Discuss [33] | > [34]
-------------------------------------------------------------------------------
Authors & editors: Robert Nemiroff [35] (MTU [36] ) & Jerry Bonnell [37]
(UMCP [38] )
NASA Official: Phillip Newman Specific rights apply [39] .
NASA Web Privacy Policy and Important Notices [40]
A service of: ASD [41] at NASA [42] / GSFC [43]
& Michigan Tech. U. [44]
----------
Site notes:
[1] archivepix.html
[2] https://www.flickr.com/people/166147883@N04/
[3] https://www.mpi-hd.mpg.de/hfm/HESS/pages/collaboration/
[4] https://www.premiumbeat.com/artist/immersive-music
[5] https://www.mpi-hd.mpg.de/hfm/HESS/pages/about/telescopes/
[6] ap120727.html
[7] https://en.wikipedia.org/wiki/Cherenkov_radiation
[8] https://en.wikipedia.org/wiki/Charged_particle
[9] https://en.wikipedia.org/wiki/Speed_of_light
[10] https://science.nasa.gov/ems/12_gammarays
[11] ap060814.html
[12] https://www.mpi-hd.mpg.de/hfm/HESS/pages/about/
[13]
https://scienceblogs.com/builtonfacts/2013/11/27/
how-often-does-the-sun-emit-1-tev-photons
[14] https://en.wikipedia.org/wiki/Namibia
[15]
https://www.nasa.gov/audience/forstudents/9-12/features/
what-is-dark-matter.html
[16] http://adsabs.harvard.edu/abs/2018A%26A...612A...1H
[17] ap170518.html
[18] ap180729.html
[19] https://apod.nasa.gov/htmltest/rjn_bht.html
[20] https://vimeo.com/302897067
[21] ap180427.html
[22] ap160725.html
[23] http://ascl.net/code/all
[24] ap190107.html
[25] archivepix.html
[26] lib/apsubmit2015.html
[27] lib/aptree.html
[28] https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
[29] calendar/allyears.html
[30] /apod.rss
[31] lib/edlinks.html
[32] lib/about_apod.html
[33] http://asterisk.apod.com/discuss_apod.php?date=190108
[34] ap190109.html
[35] http://www.phy.mtu.edu/faculty/Nemiroff.html
[36] http://www.phy.mtu.edu/
[37] https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
[38] http://www.astro.umd.edu/
[39] lib/about_apod.html#srapply
[40] https://www.nasa.gov/about/highlights/HP_Privacy.html
[41] https://astrophysics.gsfc.nasa.gov/
[42] https://www.nasa.gov/
[43] https://www.nasa.gov/centers/goddard/
[44] http://www.mtu.edu/
--- Mystic BBS v1.12 A42 (Windows/32)
* Origin: FIDONet - The Positronium Repository (1:393/68)
|