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		<id>https://www.explainxkcd.com/wiki/index.php?action=history&amp;feed=atom&amp;title=Talk%3A3177%3A_Chessboard_Alignment</id>
		<title>Talk:3177: Chessboard Alignment - Revision history</title>
		<link rel="self" type="application/atom+xml" href="https://www.explainxkcd.com/wiki/index.php?action=history&amp;feed=atom&amp;title=Talk%3A3177%3A_Chessboard_Alignment"/>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;action=history"/>
		<updated>2026-04-22T00:55:12Z</updated>
		<subtitle>Revision history for this page on the wiki</subtitle>
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	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401234&amp;oldid=prev</id>
		<title>SammyChips at 16:38, 10 December 2025</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401234&amp;oldid=prev"/>
				<updated>2025-12-10T16:38:58Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 16:38, 10 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l57&quot; &gt;Line 57:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 57:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::One Problem I see with following a circular route against the gravitational isoclines is that if the boards are not tilted to be aligned with the gravitational gradient then hopefully there would be enough friction to keep the pieces from sliding off, and if they are tilted then the vertical misalignment might not be small enough to be within the tolerance. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 21:16, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::One Problem I see with following a circular route against the gravitational isoclines is that if the boards are not tilted to be aligned with the gravitational gradient then hopefully there would be enough friction to keep the pieces from sliding off, and if they are tilted then the vertical misalignment might not be small enough to be within the tolerance. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 21:16, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;:::{{w|Chess set#Pocket and travel sets}}..? [[Special:Contributions/78.144.255.82|78.144.255.82]] 21:25, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;:::{{w|Chess set#Pocket and travel sets}}..? [[Special:Contributions/78.144.255.82|78.144.255.82]] 21:25, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;::::Good idea.&amp;#160; And since they're usually a lot smaller and not held to the same standards of precision, we could probably get away with a lot more. I'm not sure why it needs micrometer precision anyway.&amp;#160; It seems that even tournament boards aren't held to anywhere close to that level. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 16:38, 10 December 2025 (UTC)&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Level doesn't mean &amp;quot;parallel to the surface of the Earth&amp;quot;, it means perpendicular to the Earth's gravitational force.[[User:Dosbears|Dosbears]] ([[User talk:Dosbears|talk]])&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Level doesn't mean &amp;quot;parallel to the surface of the Earth&amp;quot;, it means perpendicular to the Earth's gravitational force.[[User:Dosbears|Dosbears]] ([[User talk:Dosbears|talk]])&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>SammyChips</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401184&amp;oldid=prev</id>
		<title>78.144.255.82 at 21:25, 9 December 2025</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401184&amp;oldid=prev"/>
				<updated>2025-12-09T21:25:06Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 21:25, 9 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l56&quot; &gt;Line 56:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 56:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::Are we creating a {{w|Dyson swarm}} out of chess boards now? :D [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 19:38, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::Are we creating a {{w|Dyson swarm}} out of chess boards now? :D [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 19:38, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::One Problem I see with following a circular route against the gravitational isoclines is that if the boards are not tilted to be aligned with the gravitational gradient then hopefully there would be enough friction to keep the pieces from sliding off, and if they are tilted then the vertical misalignment might not be small enough to be within the tolerance. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 21:16, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::One Problem I see with following a circular route against the gravitational isoclines is that if the boards are not tilted to be aligned with the gravitational gradient then hopefully there would be enough friction to keep the pieces from sliding off, and if they are tilted then the vertical misalignment might not be small enough to be within the tolerance. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 21:16, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;:::{{w|Chess set#Pocket and travel sets}}..? [[Special:Contributions/78.144.255.82|78.144.255.82]] 21:25, 9 December 2025 (UTC)&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Level doesn't mean &amp;quot;parallel to the surface of the Earth&amp;quot;, it means perpendicular to the Earth's gravitational force.[[User:Dosbears|Dosbears]] ([[User talk:Dosbears|talk]])&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Level doesn't mean &amp;quot;parallel to the surface of the Earth&amp;quot;, it means perpendicular to the Earth's gravitational force.[[User:Dosbears|Dosbears]] ([[User talk:Dosbears|talk]])&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>78.144.255.82</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401182&amp;oldid=prev</id>
		<title>SammyChips at 21:16, 9 December 2025</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401182&amp;oldid=prev"/>
				<updated>2025-12-09T21:16:58Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 21:16, 9 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l55&quot; &gt;Line 55:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 55:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;:Aside from raising/lowering source and (where necessary) target boards to be level ''and'' realign to be square-accurate (divide the current mismatch, beyond the minor tolerance allowance, by 2.pi and shift the board(s) up or down by that amount... Perhaps move further to invoke resonance of all axes of distance, especially if on an ellipsoid, by choosing overlapping resonances in their near-integer multiples of the respective distances), one need not have to conform to the geoidal multi-term hybrid elliposodal shape, but merely take radius-from-the-core as the (identical) altitude, irrespective of local Mean Sea Level or other gravitic isoline contouring. This may involve towers/blimps and mineshafts/submersibles to match up everything, despite actual local geodic variation, but if you're measuring round-the-world distances to micrometer-accuracy then it's just a matter of applying that same accuracy to the obvious solution. [[Special:Contributions/82.132.236.87|82.132.236.87]] 18:22, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;:Aside from raising/lowering source and (where necessary) target boards to be level ''and'' realign to be square-accurate (divide the current mismatch, beyond the minor tolerance allowance, by 2.pi and shift the board(s) up or down by that amount... Perhaps move further to invoke resonance of all axes of distance, especially if on an ellipsoid, by choosing overlapping resonances in their near-integer multiples of the respective distances), one need not have to conform to the geoidal multi-term hybrid elliposodal shape, but merely take radius-from-the-core as the (identical) altitude, irrespective of local Mean Sea Level or other gravitic isoline contouring. This may involve towers/blimps and mineshafts/submersibles to match up everything, despite actual local geodic variation, but if you're measuring round-the-world distances to micrometer-accuracy then it's just a matter of applying that same accuracy to the obvious solution. [[Special:Contributions/82.132.236.87|82.132.236.87]] 18:22, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::Are we creating a {{w|Dyson swarm}} out of chess boards now? :D [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 19:38, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::Are we creating a {{w|Dyson swarm}} out of chess boards now? :D [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 19:38, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;::One Problem I see with following a circular route against the gravitational isoclines is that if the boards are not tilted to be aligned with the gravitational gradient then hopefully there would be enough friction to keep the pieces from sliding off, and if they are tilted then the vertical misalignment might not be small enough to be within the tolerance. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 21:16, 9 December 2025 (UTC)&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Level doesn't mean &amp;quot;parallel to the surface of the Earth&amp;quot;, it means perpendicular to the Earth's gravitational force.[[User:Dosbears|Dosbears]] ([[User talk:Dosbears|talk]])&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Level doesn't mean &amp;quot;parallel to the surface of the Earth&amp;quot;, it means perpendicular to the Earth's gravitational force.[[User:Dosbears|Dosbears]] ([[User talk:Dosbears|talk]])&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>SammyChips</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401180&amp;oldid=prev</id>
		<title>Dosbears: Definition of 'level'</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401180&amp;oldid=prev"/>
				<updated>2025-12-09T20:39:05Z</updated>
		
		<summary type="html">&lt;p&gt;Definition of &amp;#039;level&amp;#039;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 20:39, 9 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l55&quot; &gt;Line 55:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 55:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;:Aside from raising/lowering source and (where necessary) target boards to be level ''and'' realign to be square-accurate (divide the current mismatch, beyond the minor tolerance allowance, by 2.pi and shift the board(s) up or down by that amount... Perhaps move further to invoke resonance of all axes of distance, especially if on an ellipsoid, by choosing overlapping resonances in their near-integer multiples of the respective distances), one need not have to conform to the geoidal multi-term hybrid elliposodal shape, but merely take radius-from-the-core as the (identical) altitude, irrespective of local Mean Sea Level or other gravitic isoline contouring. This may involve towers/blimps and mineshafts/submersibles to match up everything, despite actual local geodic variation, but if you're measuring round-the-world distances to micrometer-accuracy then it's just a matter of applying that same accuracy to the obvious solution. [[Special:Contributions/82.132.236.87|82.132.236.87]] 18:22, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;:Aside from raising/lowering source and (where necessary) target boards to be level ''and'' realign to be square-accurate (divide the current mismatch, beyond the minor tolerance allowance, by 2.pi and shift the board(s) up or down by that amount... Perhaps move further to invoke resonance of all axes of distance, especially if on an ellipsoid, by choosing overlapping resonances in their near-integer multiples of the respective distances), one need not have to conform to the geoidal multi-term hybrid elliposodal shape, but merely take radius-from-the-core as the (identical) altitude, irrespective of local Mean Sea Level or other gravitic isoline contouring. This may involve towers/blimps and mineshafts/submersibles to match up everything, despite actual local geodic variation, but if you're measuring round-the-world distances to micrometer-accuracy then it's just a matter of applying that same accuracy to the obvious solution. [[Special:Contributions/82.132.236.87|82.132.236.87]] 18:22, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::Are we creating a {{w|Dyson swarm}} out of chess boards now? :D [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 19:38, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;::Are we creating a {{w|Dyson swarm}} out of chess boards now? :D [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 19:38, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Level doesn't mean &amp;quot;parallel to the surface of the Earth&amp;quot;, it means perpendicular to the Earth's gravitational force.[[User:Dosbears|Dosbears]] ([[User talk:Dosbears|talk]])&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Dosbears</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401177&amp;oldid=prev</id>
		<title>SammyChips at 19:38, 9 December 2025</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401177&amp;oldid=prev"/>
				<updated>2025-12-09T19:38:26Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 19:38, 9 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l54&quot; &gt;Line 54:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 54:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid is always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge {{citation needed}}. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:34, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid is always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge {{citation needed}}. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:34, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;:Aside from raising/lowering source and (where necessary) target boards to be level ''and'' realign to be square-accurate (divide the current mismatch, beyond the minor tolerance allowance, by 2.pi and shift the board(s) up or down by that amount... Perhaps move further to invoke resonance of all axes of distance, especially if on an ellipsoid, by choosing overlapping resonances in their near-integer multiples of the respective distances), one need not have to conform to the geoidal multi-term hybrid elliposodal shape, but merely take radius-from-the-core as the (identical) altitude, irrespective of local Mean Sea Level or other gravitic isoline contouring. This may involve towers/blimps and mineshafts/submersibles to match up everything, despite actual local geodic variation, but if you're measuring round-the-world distances to micrometer-accuracy then it's just a matter of applying that same accuracy to the obvious solution. [[Special:Contributions/82.132.236.87|82.132.236.87]] 18:22, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;:Aside from raising/lowering source and (where necessary) target boards to be level ''and'' realign to be square-accurate (divide the current mismatch, beyond the minor tolerance allowance, by 2.pi and shift the board(s) up or down by that amount... Perhaps move further to invoke resonance of all axes of distance, especially if on an ellipsoid, by choosing overlapping resonances in their near-integer multiples of the respective distances), one need not have to conform to the geoidal multi-term hybrid elliposodal shape, but merely take radius-from-the-core as the (identical) altitude, irrespective of local Mean Sea Level or other gravitic isoline contouring. This may involve towers/blimps and mineshafts/submersibles to match up everything, despite actual local geodic variation, but if you're measuring round-the-world distances to micrometer-accuracy then it's just a matter of applying that same accuracy to the obvious solution. [[Special:Contributions/82.132.236.87|82.132.236.87]] 18:22, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;::Are we creating a {{w|Dyson swarm}} out of chess boards now? :D [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 19:38, 9 December 2025 (UTC)&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>SammyChips</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401162&amp;oldid=prev</id>
		<title>82.132.236.87 at 18:22, 9 December 2025</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401162&amp;oldid=prev"/>
				<updated>2025-12-09T18:22:11Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 18:22, 9 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l13&quot; &gt;Line 13:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 13:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid in always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge [citation needed]. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:33, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid in always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge [citation needed]. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:33, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Do you have to consider other boards to avoid castling through check? [[Special:Contributions/2600:100C:B29E:1DBD:C9D:1FF3:39A0:FC2E|2600:100C:B29E:1DBD:C9D:1FF3:39A0:FC2E]] 20:19, 6 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Do you have to consider other boards to avoid castling through check? [[Special:Contributions/2600:100C:B29E:1DBD:C9D:1FF3:39A0:FC2E|2600:100C:B29E:1DBD:C9D:1FF3:39A0:FC2E]] 20:19, 6 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;:The whole fuss could be eliminated by just choosing an 'altitude'/radius from Earth's barycentre and ignoring such localised variations (off-spheroid or even off-ellipsoid) in which particular contour line is applicable for the intersection of a 'spherically level' projection out from one board to another. Even with two separate (elipsoidally-dictated) offsets from perpendicular axis off of board (maybe even also with the diagonals), itnkay be possible to elevate/bury boards sufficiently (against local surface height) to make both(/all) round-the-world offsets an integer number of squares, to within the stated tolerances, for every vertical change in distance, ''v'', it would adjust the horizontal offset ''h'' by ''2.pi.v''&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;I think a funnier title text would've been: Bfi8(!!!) [[User:Fephisto|Fephisto]] ([[User talk:Fephisto|talk]]) 06:22, 6 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;I think a funnier title text would've been: Bfi8(!!!) [[User:Fephisto|Fephisto]] ([[User talk:Fephisto|talk]]) 06:22, 6 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l52&quot; &gt;Line 52:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 53:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid is always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge {{citation needed}}. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:34, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid is always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge {{citation needed}}. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:34, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;:Aside from raising/lowering source and (where necessary) target boards to be level ''and'' realign to be square-accurate (divide the current mismatch, beyond the minor tolerance allowance, by 2.pi and shift the board(s) up or down by that amount... Perhaps move further to invoke resonance of all axes of distance, especially if on an ellipsoid, by choosing overlapping resonances in their near-integer multiples of the respective distances), one need not have to conform to the geoidal multi-term hybrid elliposodal shape, but merely take radius-from-the-core as the (identical) altitude, irrespective of local Mean Sea Level or other gravitic isoline contouring. This may involve towers/blimps and mineshafts/submersibles to match up everything, despite actual local geodic variation, but if you're measuring round-the-world distances to micrometer-accuracy then it's just a matter of applying that same accuracy to the obvious solution. [[Special:Contributions/82.132.236.87|82.132.236.87]] 18:22, 9 December 2025 (UTC)&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>82.132.236.87</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401156&amp;oldid=prev</id>
		<title>SammyChips at 17:38, 9 December 2025</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401156&amp;oldid=prev"/>
				<updated>2025-12-09T17:38:57Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 17:38, 9 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l51&quot; &gt;Line 51:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 51:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The text currently says, &amp;quot;A perfect line of chessboards placed end-to-end on the surface of an Earth-sized sphere ... would form a great circle&amp;quot;, which isn't quite right because a line of chessboards has some width to it and therefore isn't a line. You could align chessboards to form a great circle out of their left edges, or their right edges, or any one inter-square line. Not sure how to fix this. [[User:DKMell|DKMell]] ([[User talk:DKMell|talk]]) 18:04, 8 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The text currently says, &amp;quot;A perfect line of chessboards placed end-to-end on the surface of an Earth-sized sphere ... would form a great circle&amp;quot;, which isn't quite right because a line of chessboards has some width to it and therefore isn't a line. You could align chessboards to form a great circle out of their left edges, or their right edges, or any one inter-square line. Not sure how to fix this. [[User:DKMell|DKMell]] ([[User talk:DKMell|talk]]) 18:04, 8 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid is always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;[&lt;/del&gt;citation needed&lt;del class=&quot;diffchange diffchange-inline&quot;&gt;]&lt;/del&gt;. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:34, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid is always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;{{&lt;/ins&gt;citation needed&lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;}}&lt;/ins&gt;. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:34, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>SammyChips</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401154&amp;oldid=prev</id>
		<title>SammyChips at 17:36, 9 December 2025</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401154&amp;oldid=prev"/>
				<updated>2025-12-09T17:36:09Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
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				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 17:36, 9 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l51&quot; &gt;Line 51:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 51:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The text currently says, &amp;quot;A perfect line of chessboards placed end-to-end on the surface of an Earth-sized sphere ... would form a great circle&amp;quot;, which isn't quite right because a line of chessboards has some width to it and therefore isn't a line. You could align chessboards to form a great circle out of their left edges, or their right edges, or any one inter-square line. Not sure how to fix this. [[User:DKMell|DKMell]] ([[User talk:DKMell|talk]]) 18:04, 8 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The text currently says, &amp;quot;A perfect line of chessboards placed end-to-end on the surface of an Earth-sized sphere ... would form a great circle&amp;quot;, which isn't quite right because a line of chessboards has some width to it and therefore isn't a line. You could align chessboards to form a great circle out of their left edges, or their right edges, or any one inter-square line. Not sure how to fix this. [[User:DKMell|DKMell]] ([[User talk:DKMell|talk]]) 18:04, 8 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;−&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid &lt;del class=&quot;diffchange diffchange-inline&quot;&gt;in &lt;/del&gt;always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge [citation needed]. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:34, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid &lt;ins class=&quot;diffchange diffchange-inline&quot;&gt;is &lt;/ins&gt;always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge [citation needed]. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:34, 9 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>SammyChips</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401153&amp;oldid=prev</id>
		<title>SammyChips at 17:34, 9 December 2025</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401153&amp;oldid=prev"/>
				<updated>2025-12-09T17:34:56Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 17:34, 9 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l50&quot; &gt;Line 50:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 50:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The text currently says, &amp;quot;A perfect line of chessboards placed end-to-end on the surface of an Earth-sized sphere ... would form a great circle&amp;quot;, which isn't quite right because a line of chessboards has some width to it and therefore isn't a line. You could align chessboards to form a great circle out of their left edges, or their right edges, or any one inter-square line. Not sure how to fix this. [[User:DKMell|DKMell]] ([[User talk:DKMell|talk]]) 18:04, 8 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The text currently says, &amp;quot;A perfect line of chessboards placed end-to-end on the surface of an Earth-sized sphere ... would form a great circle&amp;quot;, which isn't quite right because a line of chessboards has some width to it and therefore isn't a line. You could align chessboards to form a great circle out of their left edges, or their right edges, or any one inter-square line. Not sure how to fix this. [[User:DKMell|DKMell]] ([[User talk:DKMell|talk]]) 18:04, 8 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid in always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge [citation needed]. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:34, 9 December 2025 (UTC)&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>SammyChips</name></author>	</entry>

	<entry>
		<id>https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401152&amp;oldid=prev</id>
		<title>SammyChips at 17:33, 9 December 2025</title>
		<link rel="alternate" type="text/html" href="https://www.explainxkcd.com/wiki/index.php?title=Talk:3177:_Chessboard_Alignment&amp;diff=401152&amp;oldid=prev"/>
				<updated>2025-12-09T17:33:52Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table class=&quot;diff diff-contentalign-left&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr style=&quot;vertical-align: top;&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: white; color:black; text-align: center;&quot;&gt;Revision as of 17:33, 9 December 2025&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l11&quot; &gt;Line 11:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 11:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Did the math for 'aiming' at geostatinary satellite from while being level. https://www.wolframalpha.com/input?i=arccos%286371%2Fsqrt%2842%2C164%5E2%2B6371%5E2%29%29 . If anybody wants to check my math please do so.--[[User:Trimutius|Trimutius]] ([[User talk:Trimutius|talk]]) 19:06, 6 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Did the math for 'aiming' at geostatinary satellite from while being level. https://www.wolframalpha.com/input?i=arccos%286371%2Fsqrt%2842%2C164%5E2%2B6371%5E2%29%29 . If anybody wants to check my math please do so.--[[User:Trimutius|Trimutius]] ([[User talk:Trimutius|talk]]) 19:06, 6 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot;&gt;&amp;#160;&lt;/td&gt;&lt;td class='diff-marker'&gt;+&lt;/td&gt;&lt;td style=&quot;color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;{{w|Geodesics on an ellipsoid}} are a bit more complicated than those for a sphere (and Earth isn't really even purely ellipsoidal).&amp;#160; The geodesics aren't actually great circles, nor even closed curves except for those tilted at specific angles.&amp;#160; The curve could cover an extremely large distance before visiting a position within a specific displacement from its starting point.&amp;#160; However, because the ellipsoid in always convex, even though the radius of curvature is different depending on location and direction, two geodesics that start parallel should always converge [citation needed]. [[User:SammyChips|SammyChips]] ([[User talk:SammyChips|talk]]) 17:33, 9 December 2025 (UTC)&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Do you have to consider other boards to avoid castling through check? [[Special:Contributions/2600:100C:B29E:1DBD:C9D:1FF3:39A0:FC2E|2600:100C:B29E:1DBD:C9D:1FF3:39A0:FC2E]] 20:19, 6 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;Do you have to consider other boards to avoid castling through check? [[Special:Contributions/2600:100C:B29E:1DBD:C9D:1FF3:39A0:FC2E|2600:100C:B29E:1DBD:C9D:1FF3:39A0:FC2E]] 20:19, 6 December 2025 (UTC)&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;td class='diff-marker'&gt;&amp;#160;&lt;/td&gt;&lt;td style=&quot;background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>SammyChips</name></author>	</entry>

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