by APOD Robot » Mon Sep 17, 2018 4:10 am
Cosmic Collision Forges Galactic Ring
Explanation: How could a galaxy become shaped like a ring? The rim of the blue galaxy
pictured on the right is an immense ring-like structure 150,000
light years in diameter composed of newly formed, extremely bright, massive stars. That galaxy,
AM 0644-741, is known as a
ring galaxy and was caused by an immense galaxy collision. When
galaxies collide, they pass through each other -- their individual stars rarely come into contact. The
ring-like shape is the result of the
gravitational disruption caused by an entire
small intruder galaxy passing through a large one. When this happens, interstellar gas and
dust become condensed, causing a
wave of star formation to move out from the impact point like a ripple across the surface of a pond. The likely intruder galaxy is on the left of this combined image from
Hubble (
visible) and
Chandra (
X-ray) space telescopes. X-ray light is shown in pink and
depicts places where energetic
black holes or neutron stars, likely formed shortly after the
galaxy collision, reside.
[url=https://apod.nasa.gov/apod/ap180917.html] [img]https://apod.nasa.gov/apod/calendar/S_180917.jpg[/img] [size=150]Cosmic Collision Forges Galactic Ring[/size][/url]
[b] Explanation: [/b] How could a galaxy become shaped like a ring? The rim of the blue galaxy [url=http://chandra.si.edu/photo/2018/ring/]pictured[/url] on the right is an immense ring-like structure 150,000 [url=http://chandra.harvard.edu/photo/cosmic_distance.html]light years[/url] in diameter composed of newly formed, extremely bright, massive stars. That galaxy, [url=http://adsabs.harvard.edu/abs/1997ApJ...474..686H]AM 0644-741[/url], is known as a [url=https://apod.nasa.gov/apod/ap010612.html]ring galaxy[/url] and was caused by an immense galaxy collision. When [url=https://apod.nasa.gov/apod/ap150201.html]galaxies collide[/url], they pass through each other -- their individual stars rarely come into contact. The [url=http://en.wikipedia.org/wiki/Engagement_ring]ring[/url]-like shape is the result of the [url=http://en.wikipedia.org/wiki/Tidal_force]gravitational disruption[/url] caused by an entire [url=https://s-media-cache-ak0.pinimg.com/736x/5b/60/1e/5b601e8413f01f169a27dffd3a1e1601.jpg]small intruder[/url] galaxy passing through a large one. When this happens, interstellar gas and [url=https://apod.nasa.gov/apod/ap030706.html]dust[/url] become condensed, causing a [url=http://astronomy.swin.edu.au/cosmos/D/density+wave+model]wave of star formation[/url] to move out from the impact point like a ripple across the surface of a pond. The likely intruder galaxy is on the left of this combined image from [url=http://www.stsci.edu/hst/HST_overview/]Hubble[/url] ([url=https://science.nasa.gov/ems/09_visiblelight]visible[/url]) and [url=https://www.nasa.gov/mission_pages/chandra/main/index.html]Chandra[/url] ([url=https://science.nasa.gov/ems/11_xrays]X-ray[/url]) space telescopes. X-ray light is shown in pink and [url=https://www.youtube.com/watch?v=FgbmB_yLbZ0]depicts places[/url] where energetic [url=https://apod.nasa.gov/htmltest/rjn_bht.html]black holes or neutron stars[/url], likely formed shortly after the [url=https://apod.nasa.gov/apod/ap130514.html]galaxy collision[/url], reside.
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