by APOD Robot » Tue Dec 29, 2009 4:55 am
Rigel and the Witch Head Nebula
Explanation: Double, double toil and trouble; Fire burn, and cauldron bubble -- maybe
Macbeth should have consulted the Witch Head Nebula. This suggestively shaped
reflection nebula on the lower left is associated with the
bright star Rigel, to its right, in the
constellation Orion. More formally known as
IC 2118, the Witch Head Nebula glows primarily by light reflected from
Rigel. Fine
dust in the nebula reflects the light.
Pictured above, the blue color of the Witch Head Nebula and of the dust surrounding
Rigel is caused not only by
Rigel's blue color but because the
dust grains reflect blue light more efficiently than red. The same
physical process causes
Earth's daytime sky to appear blue, although the scatterers in
Earth's atmosphere are molecules of
nitrogen and
oxygen. Rigel, the
Witch Head Nebula, and gas and dust that surrounds them lie about 800
light-years away.
[url=http://apod.nasa.gov/apod/ap091229.html][img]http://apod.nasa.gov/apod/calendar/S_091229.jpg[/img] [size=150]Rigel and the Witch Head Nebula[/size][/url]
[b] Explanation: [/b] Double, double toil and trouble; Fire burn, and cauldron bubble -- maybe [url=http://the-tech.mit.edu/Shakespeare/macbeth/]Macbeth[/url] should have consulted the Witch Head Nebula. This suggestively shaped [url=http://apod.nasa.gov/apod/reflection_nebulae.html]reflection nebula[/url] on the lower left is associated with the [url=http://www.astro.uiuc.edu/~kaler/sow/rigel.html]bright star Rigel[/url], to its right, in the [url=http://www.astro.uiuc.edu/~kaler/sow/orion-p.html]constellation Orion[/url]. More formally known as [url=http://en.wikipedia.org/wiki/IC_2118]IC 2118[/url], the Witch Head Nebula glows primarily by light reflected from [url=http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1997MNRAS.290..521I]Rigel[/url]. Fine [url=http://apod.nasa.gov/apod/ap030706.html]dust[/url] in the nebula reflects the light. [url=http://deepskycolors.com/pics/astro/2009/11/mb_2009-11-16_WitchHead.jpg]Pictured above[/url], the blue color of the Witch Head Nebula and of the dust surrounding [url=http://www.youtube.com/watch?v=c8CgDGhYKe8]Rigel[/url] is caused not only by [url=http://en.wikipedia.org/wiki/Rigel]Rigel[/url]'s blue color but because the [url=http://leo.astronomy.cz/mix/mix.html]dust grains reflect blue light[/url] more efficiently than red. The same [url=http://hyperphysics.phy-astr.gsu.edu/hbase/atmos/blusky.html]physical process[/url] causes [url=http://math.ucr.edu/home/baez/physics/General/BlueSky/blue_sky.html]Earth's daytime sky to appear blue[/url], although the scatterers in [url=http://csep10.phys.utk.edu/astr161/lect/earth/atmosphere.html]Earth's atmosphere[/url] are molecules of [url=http://periodic.lanl.gov/elements/7.html]nitrogen[/url] and [url=http://periodic.lanl.gov/elements/8.html]oxygen[/url]. Rigel, the [url=http://apod.nasa.gov/apod/ap061211.html]Witch Head Nebula[/url], and gas and dust that surrounds them lie about 800 [url=http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html]light-years[/url] away.
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