Editing Talk:1276: Angular Size
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I haven't done any lookups or maths to check these, but give the size of these as "stars" in the sky, everything from panel 2 onwards seems to me to be an order of magnitude or two too large. [[User:Markhurd|Mark Hurd]] ([[User talk:Markhurd|talk]]) 05:17, 11 October 2013 (UTC) | I haven't done any lookups or maths to check these, but give the size of these as "stars" in the sky, everything from panel 2 onwards seems to me to be an order of magnitude or two too large. [[User:Markhurd|Mark Hurd]] ([[User talk:Markhurd|talk]]) 05:17, 11 October 2013 (UTC) | ||
: Not really. You see the stars and planets as points because their angular size is lower than your eyes' resolution. They have measurable (or, in case of really distant or small objects, computable) angular sizes. For stars etc. these angular sizes are really small - but Earth is quite big, so if you cut a portion of a sphere the radius of Earth corresponding to these small solid angles, you get sizable areas. I haven't checked Randall's math, but I'd rather believe his results. If it is non-intuitive for you consider the Sun and Moon example - when observed by naked eye, the Moon looks for you as being the size of a dime held up in your hand - and yet it's shadow during an eclipse covers quite an area of Earth's surface. It is true that sizes of some of these "footprints" are quite surprising compared to other ones. [[Special:Contributions/89.174.214.74|89.174.214.74]] 08:55, 11 October 2013 (UTC) | : Not really. You see the stars and planets as points because their angular size is lower than your eyes' resolution. They have measurable (or, in case of really distant or small objects, computable) angular sizes. For stars etc. these angular sizes are really small - but Earth is quite big, so if you cut a portion of a sphere the radius of Earth corresponding to these small solid angles, you get sizable areas. I haven't checked Randall's math, but I'd rather believe his results. If it is non-intuitive for you consider the Sun and Moon example - when observed by naked eye, the Moon looks for you as being the size of a dime held up in your hand - and yet it's shadow during an eclipse covers quite an area of Earth's surface. It is true that sizes of some of these "footprints" are quite surprising compared to other ones. [[Special:Contributions/89.174.214.74|89.174.214.74]] 08:55, 11 October 2013 (UTC) | ||
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Does someone know how to use LaTeX formulas? And if so, can they translate my formula into something more pleasing to the eye? [[User:Irino.|Irino.]] ([[User talk:Irino.|talk]]) 05:49, 11 October 2013 (UTC) | Does someone know how to use LaTeX formulas? And if so, can they translate my formula into something more pleasing to the eye? [[User:Irino.|Irino.]] ([[User talk:Irino.|talk]]) 05:49, 11 October 2013 (UTC) | ||
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Neither the sun or moon, nor Messier 25 (declination -19°) can ever culminate in the zenith over London. :-( Admittedly, Townsville, Australia would be sort of overwhelmed by M25. --[[Special:Contributions/129.13.72.198|129.13.72.198]] 11:27, 11 October 2013 (UTC) | Neither the sun or moon, nor Messier 25 (declination -19°) can ever culminate in the zenith over London. :-( Admittedly, Townsville, Australia would be sort of overwhelmed by M25. --[[Special:Contributions/129.13.72.198|129.13.72.198]] 11:27, 11 October 2013 (UTC) | ||
: M25 is a reference to the highway that surrounds London, not the Messier object, which is probably nowhere near the angular size of the moon. [[Special:Contributions/65.129.214.100|65.129.214.100]] 15:17, 11 October 2013 (UTC) | : M25 is a reference to the highway that surrounds London, not the Messier object, which is probably nowhere near the angular size of the moon. [[Special:Contributions/65.129.214.100|65.129.214.100]] 15:17, 11 October 2013 (UTC) | ||
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Does anyone know why the exoplanet "HD 189733 b" is labled as "Permadeath" ? Same question for the other weird names in the same pannel (the "tilde on keyboard" one) ? [[User:Jahvascriptmaniac|Jahvascriptmaniac]] ([[User talk:Jahvascriptmaniac|talk]]) 11:32, 11 October 2013 (UTC) | Does anyone know why the exoplanet "HD 189733 b" is labled as "Permadeath" ? Same question for the other weird names in the same pannel (the "tilde on keyboard" one) ? [[User:Jahvascriptmaniac|Jahvascriptmaniac]] ([[User talk:Jahvascriptmaniac|talk]]) 11:32, 11 October 2013 (UTC) | ||
: A reference to [[1253|Exoplanet Names]]. [[User:Squornshellous Beta|Squornshellous Beta]] ([[User talk:Squornshellous Beta|talk]]) 12:08, 11 October 2013 (UTC) | : A reference to [[1253|Exoplanet Names]]. [[User:Squornshellous Beta|Squornshellous Beta]] ([[User talk:Squornshellous Beta|talk]]) 12:08, 11 October 2013 (UTC) | ||
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If you were looking from the center of the earth, as the situation suggests, wouldn't the M25 be reversed, east-to-west, as you look at the sun and the moon?--[[Special:Contributions/76.105.133.220|76.105.133.220]] 16:09, 11 October 2013 (UTC) | If you were looking from the center of the earth, as the situation suggests, wouldn't the M25 be reversed, east-to-west, as you look at the sun and the moon?--[[Special:Contributions/76.105.133.220|76.105.133.220]] 16:09, 11 October 2013 (UTC) | ||
: I visualize it as looking down on Earth, with the "shadow" of the celestial object on top of the M25/soccer field/laptop/etc. [[Special:Contributions/67.51.59.66|67.51.59.66]] 17:02, 11 October 2013 (UTC) | : I visualize it as looking down on Earth, with the "shadow" of the celestial object on top of the M25/soccer field/laptop/etc. [[Special:Contributions/67.51.59.66|67.51.59.66]] 17:02, 11 October 2013 (UTC) | ||
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