deep-sky object

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deep-sky object

(dēp′skī′)
n.
Any of various celestial objects, including nebulae, star clusters, and galaxies, that are diffuse and very distant, and therefore faint, usually observable only by means of a telescope.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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Many free resources for beginners and those at intermediate level are available from the ASSA website: the Southern Star Wheel planisphere, the ConCards (constellation and deep-sky object finder charts) and the comprehensive Deep-Sky Observer's Companion (DOC) tutorial.
The constellation's only relatively famous deep-sky object other than its double stars is the globular star cluster M30, a respectably bright (7th magnitude) and interesting object.
Many resources for beginners and those at intermediate level are available from the ASSA website, including the Southern Star Wheel planisphere, ConCards (constellation and deep-sky object finder charts) and the comprehensive Deepsky Observer's Companion tutorial.
It's probably the youngest deep-sky object you'll ever see -so young that it has changed significantly since Messier first spotted it.
Many resources for beginners and those at intermediate level are available from the Section, including the Southern Star Wheel planisphere, ConCards (constellation and deep-sky object finder charts), the Discover!
Once they get past the Moon, bright planets, and a vivid deep-sky object or two, they run out of interesting things to observe.
If there's one big category of deep-sky object that binoculars are best at showing, it's undoubtedly open clusters.
Hercules is the constellation that spells "summer" for me, and Messier 13, the Great Globular Star Cluster, is undoubtedly Here's premiere deep-sky object. Tonight we'll bypass it for another globular, one most of us haven't looked at quite as many times.
If I had to choose just one deep-sky object to demonstrate the appeal of binocular astronomy, it would probably be the Pleiades (M45) in Taurus.
Perhaps no constellation is more strongly associated with a single deep-sky object than Andromeda.
Dark nebulae are one class of deep-sky object that doesn't get enough attention.
Topics are organized by season for quick and easy identification, as Jonathan Poppele offers observation tips and instructions on everything from the moon, planets, and deep-sky objects to the ecliptic and the zodiac.
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