Difference between revisions of "Talk:2985: Craters"

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(Great Circles are not weird.)
(Delaware/Pennsylvania Arc: Response)
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:The "Delaware/Pennsylvania arc" has a long and juicy history. Not a circle. [https://en.wikipedia.org/wiki/Twelve-Mile_Circle Twelve-Mile Circle] Signed- --[[User:PRR|PRR]] ([[User talk:PRR|talk]]) 20:36, 13 September 2024 (UTC)
 
:The "Delaware/Pennsylvania arc" has a long and juicy history. Not a circle. [https://en.wikipedia.org/wiki/Twelve-Mile_Circle Twelve-Mile Circle] Signed- --[[User:PRR|PRR]] ([[User talk:PRR|talk]]) 20:36, 13 September 2024 (UTC)
 
:True about map projections, but the Venn section title here does say *Weird*.  The Delaware/Pennsylvania arc is indeed "weird"; few other such arcs are found in regular map content, and the original story for it is indeed uncommon. Great Circle arcs aren't weird in either way. [[Special:Contributions/172.68.34.64|172.68.34.64]] 20:52, 13 September 2024 (UTC)
 
:True about map projections, but the Venn section title here does say *Weird*.  The Delaware/Pennsylvania arc is indeed "weird"; few other such arcs are found in regular map content, and the original story for it is indeed uncommon. Great Circle arcs aren't weird in either way. [[Special:Contributions/172.68.34.64|172.68.34.64]] 20:52, 13 September 2024 (UTC)
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::North-South lines are great-circle arcs, but non-equatorial East-West lines - as well as many diagonal ones - are minor-circle arcs (is that the right term?), just link the 12-Mile Circle. (Let's see if this retains my IP address from my top post.) [[Special:Contributions/172.70.46.109|172.70.46.109]] 21:29, 13 September 2024 (UTC)
 +
 
==Great Blue Hole==
 
==Great Blue Hole==
 
There are two Great Blue Holes, one in Belize, one in Dahab, Egypt (Red Sea). [[Special:Contributions/172.71.102.20|172.71.102.20]] 19:11, 13 September 2024 (UTC)
 
There are two Great Blue Holes, one in Belize, one in Dahab, Egypt (Red Sea). [[Special:Contributions/172.71.102.20|172.71.102.20]] 19:11, 13 September 2024 (UTC)
 
==Recent Google Maps discovery==
 
==Recent Google Maps discovery==
 
This may be inspired Joël Lapointe's very recently announced discovery of a 15km-diameter "pit" he found near Marsal Lake (Quebec) using Google Maps. [https://www.cbc.ca/news/canada/montreal/quebec-meteorite-impact-crater-1.7313418 "He saw a suspicious pit on Google Maps. Experts say it could be a crater from an ancient space rock"] [[Special:Contributions/172.69.64.185|172.69.64.185]] 20:10, 13 September 2024 (UTC)
 
This may be inspired Joël Lapointe's very recently announced discovery of a 15km-diameter "pit" he found near Marsal Lake (Quebec) using Google Maps. [https://www.cbc.ca/news/canada/montreal/quebec-meteorite-impact-crater-1.7313418 "He saw a suspicious pit on Google Maps. Experts say it could be a crater from an ancient space rock"] [[Special:Contributions/172.69.64.185|172.69.64.185]] 20:10, 13 September 2024 (UTC)

Revision as of 21:29, 13 September 2024

Delaware/Pennsylvania Arc

The Delaware/Pennsylvania arc is a circle, sure, but so is every other allegedly "straight" line on the map. The 49N parallel looks like a straight line on some projections, but a polar projection shows that it is clearly a circle around a point on the Earth's axis. The Delaware/Pennsylvania arc is only unique for NOT being aligned with the axis. 172.71.102.20 19:07, 13 September 2024 (UTC)

The "Delaware/Pennsylvania arc" has a long and juicy history. Not a circle. Twelve-Mile Circle Signed- --PRR (talk) 20:36, 13 September 2024 (UTC)
True about map projections, but the Venn section title here does say *Weird*. The Delaware/Pennsylvania arc is indeed "weird"; few other such arcs are found in regular map content, and the original story for it is indeed uncommon. Great Circle arcs aren't weird in either way. 172.68.34.64 20:52, 13 September 2024 (UTC)
North-South lines are great-circle arcs, but non-equatorial East-West lines - as well as many diagonal ones - are minor-circle arcs (is that the right term?), just link the 12-Mile Circle. (Let's see if this retains my IP address from my top post.) 172.70.46.109 21:29, 13 September 2024 (UTC)

Great Blue Hole

There are two Great Blue Holes, one in Belize, one in Dahab, Egypt (Red Sea). 172.71.102.20 19:11, 13 September 2024 (UTC)

Recent Google Maps discovery

This may be inspired Joël Lapointe's very recently announced discovery of a 15km-diameter "pit" he found near Marsal Lake (Quebec) using Google Maps. "He saw a suspicious pit on Google Maps. Experts say it could be a crater from an ancient space rock" 172.69.64.185 20:10, 13 September 2024 (UTC)