by APOD Robot » Wed Dec 09, 2015 5:13 am
Arp 87: Merging Galaxies from Hubble
Explanation: This dance is to the death. Along the way, as these two large galaxies duel, a
cosmic bridge of stars, gas, and dust currently stretches over 75,000
light-years and joins them. The bridge itself is strong evidence that these two immense star systems have
passed close to each other and experienced violent tides induced by
mutual gravity. As further evidence, the face-on spiral galaxy on the right, also known as NGC 3808A, exhibits many young blue star clusters produced in a burst of star formation. The twisted edge-on spiral on the left (NGC 3808B) seems to be wrapped in the material
bridging the galaxies and surrounded by a curious
polar ring. Together, the system is known as
Arp 87 and morphologically classified, technically, as
peculiar. While such interactions are drawn out over billions of years, repeated
close passages should ultimately result in the death of one galaxy in the sense that only one galaxy will eventually result. Although
this scenario does look peculiar, galactic mergers are thought to be common, with Arp 87 representing a stage in
this inevitable process. The Arp 87 pair are
about 300 million light-years distant toward the constellation Leo. The prominent edge-on spiral at the far left appears to be a more distant background galaxy and not involved in the on-going merger.
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[url=http://apod.nasa.gov/apod/ap151209.html][img]http://apod.nasa.gov/apod/calendar/S_151209.jpg[/img] [size=150]Arp 87: Merging Galaxies from Hubble[/size][/url]
[b] Explanation: [/b] This dance is to the death. Along the way, as these two large galaxies duel, a [url=http://apod.nasa.gov/apod/ap140715.html]cosmic bridge[/url] of stars, gas, and dust currently stretches over 75,000 [url=http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html]light-years[/url] and joins them. The bridge itself is strong evidence that these two immense star systems have [url=http://apod.nasa.gov/apod/ap130514.html]passed close[/url] to each other and experienced violent tides induced by [url=http://burro.cwru.edu/JavaLab/GalCrashWeb/main.html]mutual gravity[/url]. As further evidence, the face-on spiral galaxy on the right, also known as NGC 3808A, exhibits many young blue star clusters produced in a burst of star formation. The twisted edge-on spiral on the left (NGC 3808B) seems to be wrapped in the material [url=http://apod.nasa.gov/apod/ap061111.html]bridging the galaxies[/url] and surrounded by a curious [url=http://apod.nasa.gov/apod/ap141108.html]polar ring[/url]. Together, the system is known as [url=http://heritage.stsci.edu/2007/36/index.html]Arp 87[/url] and morphologically classified, technically, as [url=http://nedwww.ipac.caltech.edu/level5/Arp/frames.html]peculiar[/url]. While such interactions are drawn out over billions of years, repeated [url=http://apod.nasa.gov/apod/ap120717.html]close passages[/url] should ultimately result in the death of one galaxy in the sense that only one galaxy will eventually result. Although [url=http://adsabs.harvard.edu/abs/1972ApJ...178..623T]this scenario[/url] does look peculiar, galactic mergers are thought to be common, with Arp 87 representing a stage in [url=http://www.cv.nrao.edu/~jhibbard/MergeSeq/mergeseq.html]this inevitable process[/url]. The Arp 87 pair are [url=http://hubblesite.org/newscenter/archive/releases/2007/36/fastfacts/]about 300 million light-years[/url] distant toward the constellation Leo. The prominent edge-on spiral at the far left appears to be a more distant background galaxy and not involved in the on-going merger.
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