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362:{\displaystyle 4\pi \left({\frac {180}{\pi }}\right)^{2}\,{\deg }^{2}={\frac {360^{2}}{\pi }}\,\,{\deg }^{2}={\frac {129\,600}{\pi }}\,\,{\deg }^{2}\approx 41\,252.96\,\,{\deg }^{2}}
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of the sky when viewed from the surface of the Earth. The Moon is only a half degree across (i.e. a circular diameter of roughly
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Assuming the Earth to be a sphere with a surface area of 510 million km, the area of
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are used to measure parts of a circle, square degrees are used to measure parts of a
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is roughly half a degree across (the same as the full moon) and covers only
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times the full moon (or the Sun) to cover the entire celestial sphere.
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Conversely, an average full moon (or the Sun) covers a 2 /
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602:"Square Degrees - the Area of something on the sky"
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445:fraction, or less than 1/1000 of a percent (
141: radians, a square degree is equal to (
574:"RASC Calgary Centre - The Constellations"
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123:. Analogous to one degree being equal to
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604:. The RASC Calgary Centre. 2018-11-05
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554:List of constellations by area
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111:. Other denotations include
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16:Measure of solid angle
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196:has a solid angle of
626:Units of solid angle
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544:Spat (angular unit)
57:... is equal to ...
382:covers only about
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181: sr or about
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495:Equatorial Guinea
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115:and (°). Just as
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606:. Retrieved
581:. Retrieved
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423:0.2 deg
384:0.2 deg
194:whole sphere
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27:Unit of
526:68 deg
479:Connecticut
109:solid angle
107:measure of
100:) is a non-
50:1 deg
31:Solid angle
608:2022-01-21
583:2022-02-16
560:References
507:2 deg
187:10 sr
161:steradians
85:10 sr
539:Steradian
380:full moon
336:≈
317:π
284:π
241:π
228:π
212: deg
620:Category
533:See also
503: km
487: km
471: km
425:as well.
373:Examples
113:sq. deg.
76:≈
70:SI units
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117:degrees
343:252.96
121:sphere
52:in ...
37:Symbol
514:Hydra
447:0.000
183:3.046
78:3.046
522:Crux
399:0.5°
388:0.5°
378:The
192:The
175:3283
105:unit
501:050
493:,
485:357
469:130
452:523
449:009
442:100
440:210
432:100
430:210
419:Sun
350:deg
326:deg
313:600
309:129
293:deg
275:360
259:deg
238:180
210:253
154:180
136:180
98:deg
40:deg
622::
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102:SI
92:A
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269:=
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233:(
225:4
200:π
198:4
185:×
171:/
168:1
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147:π
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129:π
96:(
83:×
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