https://www.explainxkcd.com/wiki/api.php?action=feedcontributions&user=173.245.52.173&feedformat=atomexplain xkcd - User contributions [en]2024-03-28T12:54:02ZUser contributionsMediaWiki 1.30.0https://www.explainxkcd.com/wiki/index.php?title=1074:_Moon_Landing&diff=949891074: Moon Landing2015-06-07T10:49:51Z<p>173.245.52.173: /* Explanation */ found the source, added the link to the tweet, cleaned up my mess.</p>
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<div>{{Comic<br />
| number = 1074<br />
| date = June 27, 2012<br />
| title = Moon Landing<br />
| image = moon_landing.png<br />
| titletext = Ok, so Spirit and Opportunity are pretty awesome. And Kepler. And New Horizons, Cassini, Curiosity, TiME, and Project M. But c'mon, if the Earth were a basketball, in 40 years no human's been more than half an inch from the surface.<br />
}}<br />
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==Explanation==<br />
The comment to which [[Cueball]] is referring is [https://twitter.com/neiltyson/status/73388356461019136 a tweet] by {{w|Neil deGrasse Tyson}}, an American astrophysicist and science communicator. As of this comic, Tyson is the "Frederick P. Rose Director" (a special honorary title) of the {{w|Hayden Planetarium}}. He has appeared on many different shows, ranging from The Discovery Channel to The Big Bang Theory.<br />
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There are a number of {{w|moon landing conspiracy theories|conspiracy theories}} claiming that the moon landing was a hoax. Tyson offers a pretty compelling argument against them, but [[Megan]] presents an even more convincing refutation, snarkily implying that NASA really hasn't done anything spectacular since 1969.<br />
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And Cueball responds with a pun on the word "burn". Burn can mean a particularly effective insult, or it can mean the consumption of fuel for propulsion. In this case, the "burn" was so effective it pushed the spaceship out of orbit (which usually takes a very large amount of burning, depending on the gravity of the planet or moon).<br />
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In the title text [[Randall]] mentions many successful {{w|NASA}} unmanned missions:<br />
*The {{w|Mars Exploration Rover|Mars rovers}} Spirit and Opportunity. Opportunity is working for over ten years on the Mars surface while Spirit is out of order. See this comic: [[695: Spirit]].<br />
*{{w|Kepler (spacecraft)|Kepler}} did find many unknown {{w|exoplanets}}<br />
*{{w|New Horizons}} is a mission to the dwarf planet {{w|Pluto}} and beyond. It's scheduled to arrive at Pluto by mid 2015.<br />
*{{w|Cassini–Huygens|Cassini}} is a probe orbiting {{w|Saturn}} since 2004.<br />
*{{w|Curiosity (rover)|Curiosity}} is an other Mars rover at the size of a small car, exploring the Mars surface since August 2012.<br />
*{{w|Titan Mare Explorer|TiME}} is a proposed mission to explore the oceans of Saturn's moon Titan.<br />
*{{w|Project M (NASA)|Project M}} is an idea to send human like robots to the Moon.<br />
The final sentence of title text notes that all manned missions since the Moon landings have taken place in low-earth orbit, which is barely far off of the Earth's surface. If the Earth were scaled to the size of a regulation basketball, approximately 24&nbsp;cm (9¼ inches) in diameter, those manned missions would have all taken place within 1.25&nbsp;cm (½ inch) of the ball's surface. At this scale the Moon would be at a distance of 7.7&nbsp;m (25.3&nbsp;ft). Unmanned missions, such as those named above or the {{w|Voyager program|Voyager}} and {{w|Mariner program|Mariner}} probes of the 1960s and 1970s, have travelled much further.<br />
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==Transcript==<br />
:[Cueball is sitting at a table with a laptop open. His hands are on the keys.]<br />
:Cueball: Hah- Neil DeGrasse Tyson has a great reply to people who doubt astronauts went to the moon.<br />
:Voice off-screen: Oh?<br />
:Cueball: "Atop 3,000 tons of rocket fuel, where ''else'' do you think they were headed?"<br />
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:[The voice off screen turns out to be Megan. She is depicted, and now Cueball is off-screen.]<br />
:Megan: Cute. But it overlooks an even simpler argument.<br />
:Cueball: Which is?<br />
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:[Both Megan and Cueball are now visible. Cueball has turned his chair around to face her.]<br />
:Megan: If NASA were willing to fake great accomplishments, they'd have a second one by now.<br />
:Cueball: ''Ouch.''<br />
:Megan: ...Too mean?<br />
:Cueball: That burn was so harsh I think you deorbited.<br />
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{{comic discussion}}<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Megan]]<br />
[[Category:Puns]]</div>173.245.52.173https://www.explainxkcd.com/wiki/index.php?title=Talk:1492:_Dress_Color&diff=85359Talk:1492: Dress Color2015-02-28T00:13:41Z<p>173.245.52.173: Comment</p>
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<div>To me, they both look blue/gold [[User:Mikemk|Mikemk]] ([[User talk:Mikemk|talk]]) 06:29, 27 February 2015 (UTC)<br />
:To me as well. The one on the right, with a lighter background, appears more bluish and the collar is a darker brown. (The collar on the left, to my eyes, matches the face on the right.) But both definitely appear bluish with a dull yellow. - Equinox [[Special:Contributions/199.27.128.120|199.27.128.120]] 16:50, 27 February 2015 (UTC)<br />
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What is the illusion supposed to be? The colors of the dress look a bit darker with the light background, but not very much. Is that the illusion? --[[Special:Contributions/141.101.80.82|141.101.80.82]] 07:07, 27 February 2015 (UTC)<br />
: Agree. To me, it looks like it's definitely light blue (maybe "cornflower"?) with pale olive stripes. "Gold" would really be a stretch. It looks like that in all lighting conditions and in both backgrounds of the strip. Did I pass some kind of color-blindness test? Or fail? [[Special:Contributions/108.162.254.133|108.162.254.133]] 07:43, 27 February 2015 (UTC)<br />
: This has nothing to do with color-blindness, but probably with certain arbitrary constants related to white-balance adjustment that differ brain-to-brain. Many people I know insist that even though the picture looks blue, it's a dress illuminated by a blue light, and based on this assumption their brain may essentially redden the whole picture to adjust for this light. The actual picture was taken in white light, not blue light. [[Special:Contributions/173.245.55.28|173.245.55.28]] 07:46, 27 February 2015 (UTC)<br />
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::It may also be related to white-balance of the MONITOR. I see original dress like black and blue and the one on left here as gold and light blue. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 10:00, 27 February 2015 (UTC)<br />
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Apparently for some people the left-hand-side's general blueishness is adjusted against by the visual system enough to make the dress look white and gold instead of blue and brown. I am not one of those people. [[Special:Contributions/173.245.55.28|173.245.55.28]] 07:43, 27 February 2015 (UTC)<br />
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Description says left for both [[Special:Contributions/141.101.98.219|141.101.98.219]] 08:37, 27 February 2015 (UTC)<br />
:Now changed. (Saw it myself before I saw your comment, and just lept straight in there. Hopefully I changed the right left so that it's right and not left the wrong left whilst producing the wrong right. Alright?) [[Special:Contributions/141.101.98.192|141.101.98.192]] 09:30, 27 February 2015 (UTC) (Also, "hello near-IP neighbour!"... The same digits, even. Creepy.)<br />
::Y'all are both from London, and probably live on the same street. Congrats! You made a friend! :) [[Special:Contributions/108.162.216.192|108.162.216.192]] 16:25, 27 February 2015 (UTC)<br />
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Are they really the same colour? 'Cause to me on the blue side it looks blue and black- while on the white side it looks white and gold. Is this normal? {{unsigned|FlyingPiggy}}<br />
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The figure on the right definitely has a beard. [[Special:Contributions/108.162.249.182|108.162.249.182]] 09:38, 27 February 2015 (UTC)<br />
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I checked with ColorZilla and the RGB values are identical. From my perspective, in the one on the left the dress appears pale blue with darker brown/gold stripes, and the one on the right appears a darker blue with lighter brown/gold stripes. [[Special:Contributions/141.101.98.63|141.101.98.63]] 10:10, 27 February 2015 (UTC)<br />
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This is just a polychromatic version of that checker shadow illusion, right? http://en.wikipedia.org/wiki/Checker_shadow_illusion [[Special:Contributions/108.162.231.38|108.162.231.38]] 10:12, 27 February 2015 (UTC)<br />
:That's what I thought too. But it looks the same (doesn't it?) and is the same (that, thankfully is non-subjective and verifiable with as little as MSPaint), so I'm at loss as to why this deserves a comic. [[Special:Contributions/141.101.104.136|141.101.104.136]] 10:47, 27 February 2015 (UTC)<br />
: This is a common optical illusion (at least I've seen this many times) - most peoples eyes perform a white balance adjustment automatically which affects the perceived colours. If your eyes don't do this then you will do well in the paint colour matching business. http://www.moillusions.com/hue-optical-illusion/ I apologise for the jarring colours in the link. {{unsigned ip|141.101.98.220}}<br />
:Here's a particularly good demonstration of the underlying "color perception" illusion (i.e. the Checker-Shadow illusion referred to above): https://www.youtube.com/watch?v=z9Sen1HTu5o [[User:Arcanechili|Arcanechili]] ([[User talk:Arcanechili|talk]]) 15:45, 27 February 2015 (UTC)<br />
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The comic is a reference to the debate around the coloration of [http://amd.c.yimg.jp/amd/20150227-00000070-zdn_n-000-2-view.jpg this dress]. The band in the middle of the image shows some of the material of the dress. To some people, including me, the dress is obviously, unquestionably black and blue. But to others, including my wife, it's obviously, unquestionably, black and gold. {{unsigned ip|103.22.200.196}}<br />
:And to others it's apparently a number of other combinations - I've seen claims of white/gold and blue/orange. However, surprisingly few people seem to have seen [http://www.romanoriginals.co.uk/invt/70931?colour=Royal-Blue this link] to the manufacturer's page for what appears to be the same dress; available in 4 colour combinations which according to the manufacturers' descriptions are ivory/black, scarlet/black, pink/black and royal-blue/black, with pictures available of all versions. As such I'm happy to accept the pictures doing the rounds are probably the blue/black variant (although most of the over-exposed versions I've seen appear light-blue/goldish-brown to me. {{unsigned ip|141.101.99.77}}<br />
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Our eyes are too efficient, which makes this illusion work. In dim light we dilate our eyes, so an enclosed room with one lamp seems bright, though it is a cave compared to the outdoors. If the bulb in our lamp is of a warm tone, our eyes adjust so we believe we see colours as though in daylight. I think that's what's happening in the dress illusion -- we are trying to allow for perceived lighting conditions in the photo -- so the actual illusion is in our guess as to what those light conditions actually are. And finally an artist quote: "I can paint you the skin of Venus with mud, provided you let me surround it as I will." - Eugene Delacroix [[Special:Contributions/108.162.242.84|108.162.242.84]] 13:28, 27 February 2015 (UTC)<br />
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Some Notes on camera color correction: it's worse than, and is not just an optical illusion. It's a camera screwup.<br />
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* [http://40.media.tumblr.com/a391a1b4b46dd6b498d379e50f96ecbc/tumblr_nkcjuq8Tdr1tnacy1o1_500.jpg Here is the original photo] as [http://swiked.tumblr.com/post/112159166305/katze-geht-meow-ijustloveyoutubers seen here]<br />
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* [http://media.tumblr.com/ec387ec0bb03230268a9e905d74097d9/tumblr_inline_nkeezsjAuH1svicb3.jpg Here is a second photo of the same dress in normal light] As [http://swiked.tumblr.com/post/112164479015/can-we-have-more-pictures-of-the-dress-please-we seen here]<br />
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* [http://www.romanoriginals.co.uk/invt/70931?colour=Royal-Blue Here is the online store where you can buy the dress]<br />
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* [http://www.romanoriginals.co.uk/content/ebiz/romanoriginals/invt/70931/70931rbl_zoom1.jpg Here is a high quality photo of the dress from the store]<br />
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* [http://imgur.com/RY2dTnW.jpg Here is an example of the color "correction" that happens when you calibrate things so that Dark Blue = White.] NOTE: This is a major readjustment of colors and there is no real color matching between the two images. White is not actually blue in this image, and up is not down, and you are not going crazy<br />
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Cheap cameras will try to adjust colors based on formulas that guess what the correct color scheme is.<br />
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If you take a photo while in the shade on a sunny day, you likely get most of your light from the bright *BLUE* sky. This can make you look awful. The camera is set up to guess the correct exposure. In this case the camera follows the rules, and guesses, wrongly, that the the overall majority color in the center of the photo is white, and transforms the rest of the colors to match<br />
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It's a camera screwup. It also depends on how bad your viewing device is behaving, because, based on how dark the screen is, you then get the optical illusion effect that Randall posted. <br />
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This is a secondary effect, and not the real reason why behind what is going on in the first place. The correct rendering of the camera screwup is going to be, on most devices with normal color rendition, white with gold. Because some monitors are lighter or darker depending on viewing angle, this also impacts color perception.<br />
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We can then get the actual optical illusion after all that. But as we have seen with good photos of the actual dress in normal light, the camera got it wrong.<br />
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TL;DR: It's a cell phone camera screwup. [[Special:Contributions/173.245.52.170|173.245.52.170]] 14:22, 27 February 2015 (UTC)ruary 2015 (UTC)<br />
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Is it possible that there's a connection between this comic and [[690: Semicontrolled Demolition]]? Some discussions I've seen about this topic involve the choice between white/gold and blue/black, so Randall coloured his dress gold/blue. --[[Special:Contributions/108.162.216.122|108.162.216.122]] 16:20, 27 February 2015 (UTC)<br />
: It's more likely due to the fact that the colors of the actual picture - that is, if you use a color picker - are roughly the same as those in the comic. [[Special:Contributions/108.162.216.111|108.162.216.111]] 17:06, 27 February 2015 (UTC)<br />
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I'm reminded of [[356: Nerd Sniping]], only the perpetrator has managed to snipe the entire interwebs {{unsigned ip|141.101.106.107}}<br />
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No one has yet mentioned that ignoring color, the two images are also mirror images of each other. On the left, the figure is looking slightly toward her own right shoulder; while on the right she is looking slightly to her own left. Most likely not at all relevant to this discussion, but usually folks on this forum are very quick to point out even insignificant details (like I'm doing right now) :) <br />
[[Special:Contributions/108.162.216.42|108.162.216.42]] 19:01, 27 February 2015 (UTC)<br />
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;Similar Illusions and explanation<br />
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I feel like this line seems out o place, or at least badly worded (using half the URL as the text...):<br />
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''"Similar types of illusions can be seen at Optical illusion#Color_and_brightness_constancies and at echalk. (requires Flash®player)."''<br />
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Also, this seems similar to the [http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html checker shadow illusion] (link to page on website with explanation of said illusion).<br />
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On another note, this page seems rather disorganized and uniformative about the phenomenon behind this illusion.<br />
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[[User:Zweisteine|Zweisteine]] ([[User talk:Zweisteine|talk]]) 19:04, 27 February 2015 (UTC)<br />
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This explanation is lacking in a particular detail: in Randall's drawing, what colors do the dresses look. I'm color blind, so they don't look different to me, but I couldn't name them. [[Special:Contributions/173.245.52.173|173.245.52.173]] 00:13, 28 February 2015 (UTC)</div>173.245.52.173https://www.explainxkcd.com/wiki/index.php?title=297:_Lisp_Cycles&diff=84367297: Lisp Cycles2015-02-11T19:27:18Z<p>173.245.52.173: /* Transcript */</p>
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<div>{{comic<br />
| number = 297<br />
| date = August 1, 2007<br />
| title = Lisp Cycles<br />
| image = lisp_cycles.png <br />
| titletext = I've just received word that the Emperor has dissolved the MIT computer science program permamently.<br />
}}<br />
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==Explanation==<br />
{{W|Lisp (programming language)|Lisp}} is one of the oldest {{W|High-level programming language|high level programming languages}}. Despite being ahead of its times, it never got enough traction and is not widely used. However, it is considered to be a very powerful language even on the present day. [https://en.wikiquote.org/wiki/Lisp_programming_language Quotes on Lisp] shows that several big names of computer science field hold Lisp in very high esteem. {{W|Eric S. Raymond}} goes as far as to say:<br />
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:Lisp is worth learning for the profound enlightenment experience you will have when you finally get it; that experience will make you a better programmer for the rest of your days, even if you never actually use Lisp itself a lot.<br />
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Lisp is also famous for its use of fully parenthesized Polish prefix notation.<br />
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In the first panel, [[Cueball]] praises Lisp, noticing that no other language can still match the awe that it strikes despite the age that Lisp has. <br />
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In the second panel, Cueball wonders that new programmers will continue learning the "Lisp arts" that make better programmers.<br />
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The third panel rerferences ''{{w|Star Wars (film)|Star Wars}}.'' Obi Wan Kenobi said these lines when he gave a lightsaber to Luke Skywalker:<br />
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:Your father's lightsaber. This is the weapon of a Jedi Knight. Not as random or as clumsy as a blaster; an elegant weapon for a more civilized age.<br />
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The title text is also a reference to ''Star Wars'' lines:<br />
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:The Imperial Senate will no longer be of any concern to us. I've just received word that the Emperor has dissolved the council permanently. The last remnants of the Old Republic have been swept away.<br />
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The {{w|Massachusetts Institute of Technology|MIT}} mentioned in the title text is the Massachusetts Institute of Technology, an institute fundamental to the development of Lisp (and Scheme, which is a version of Lisp). For about 20 years, MIT taught Scheme in its introduction to computer science course, 6.001.<br />
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==Transcript==<br />
:[Cueball is sitting at a computer, and Megan is standing behind the desk.]<br />
:Cueball: Lisp is over half a century old and it still has this perfect, timeless air about it.<br />
:Cueball: I wonder if the cycles will continue forever. A few coders from each new generation rediscovering the Lisp arts.<br />
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:[Man in Jedi robes carrying a towering stack of parentheses in his arms, speaking to Hairy.]<br />
:Jedi: These are your father's parentheses. Elegant weapons. For a more... civilized age.<br />
{{comic discussion}}<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Megan]]<br />
[[Category:Star Wars]]<br />
[[Category:Programming]]</div>173.245.52.173https://www.explainxkcd.com/wiki/index.php?title=Talk:226:_Swingset&diff=80170Talk:226: Swingset2014-12-03T15:45:38Z<p>173.245.52.173: </p>
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<div>A glass with water can be momentarily inverted at this moment and the water will not leave the glass!--DrMath 08:56, 16 November 2013 (UTC)<br />
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Isn't the point about illustrating that you do in fact have weight even in instences that are written off as weightless? In space you just happen to be falling at the same velocity of your surroundings, maintaining orbit simply by moving fast enough to miss the Earth. On top of which, in a low enough orbit g is still close to 9.8 m/s^2 if only because altitude is insignificant compared to the radius of the Earth.--Passing Stranger 14:10 August 2014 (UTC)<br />
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The woman appears to be his mother.</div>173.245.52.173https://www.explainxkcd.com/wiki/index.php?title=Talk:1389:_Surface_Area&diff=70729Talk:1389: Surface Area2014-07-02T12:31:18Z<p>173.245.52.173: </p>
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<div>FYI to whoever writes this: the Seattle reference is the Space Needle. [[Special:Contributions/108.162.221.65|108.162.221.65]] 05:03, 2 July 2014 (UTC)<br />
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Uranus is larger than all of these combined. Of course, it isn't on this map because it is full of gas. [[Special:Contributions/173.245.62.62|173.245.62.62]] 05:50, 2 July 2014 (UTC)<br />
: Just wondering... Does that mean, a spaceship could just fly trough Uranus? (No pun intended.) --[[Special:Contributions/141.101.75.20|141.101.75.20]] 07:16, 2 July 2014 (UTC)<br />
::It'd probably hurt. As an ice-giant, the interior of Uranus is mainly composed of ices and rock. Jupiter and Saturn have cores of liquid metallic hydrogen. Also, the rock/ice isn't considered the surface of Uranus, because most of the planet's mass lies outside the solid inner layers.) [[Special:Contributions/103.22.201.239|103.22.201.239]] 09:28, 2 July 2014 (UTC) P.S. Even if it was only gas, a spaceship would probably find it hard to handle the temperature and pressure at the center of Uranus.<br />
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And of course the earth is not correctly displayed: we have water which - in most cases - is not solid. -- jesterchen [[Special:Contributions/141.101.75.19|141.101.75.19]] 07:23, 2 July 2014 (UTC) <br />
: Water still has surface area. Edit: oh, I see what you mean now, from the title in the comic. I guess you have a point, but it's mainly there for comparison so it's not necessarily a mistake. --[[User:NeatNit|NeatNit]] ([[User talk:NeatNit|talk]]) 06:14, 2 July 2014 (UTC)<br />
:: Under the water there is solid bottom --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 07:01, 2 July 2014 (UTC)<br />
::: But then it is not "surface" anymore... but you two have a point. I focused mainly on the title, not the image text... So forget my comment :) -- jesterchen [[Special:Contributions/141.101.75.19|141.101.75.19]] 09:12, 2 July 2014 (UTC)<br />
:::: Water indeed has a surface, while gas doesn't. [[Special:Contributions/141.101.104.47|141.101.104.47]] 11:13, 2 July 2014 (UTC)Martin<br />
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There is also small section named "''All human skin''" (between Earth and Titan)... if you think about thread and needle... ugh... --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 07:01, 2 July 2014 (UTC)<br />
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This seems to be an island floating on something, maybe it's floating on the sun's plasma? --[[User:BelgianAtheist|BelgianAtheist]] ([[User talk:BelgianAtheist|talk]]) 08:24, 2 July 2014 (UTC)<br />
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So, what's the area surrounding Earth's landmass? It's not named, or am I blind? [[Special:Contributions/141.101.99.218|141.101.99.218]] 09:46, 2 July 2014 (UTC)<br />
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Don't think it is strictly accurate to say that earth is included 'for scale' -- surely it is included because it qualifies to be on the map. Otherwise it's a bit like saying that Belgium is included in maps of Europe 'for scale' (as 'the size of Belgium' is a well-known unit of land area as in 'Amazonian rainforest the size of Belgium is cut down every week') -- Devonian Earache<br />
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The map of Earth doesn't look like the Waterman Butterfly projection. If it did, the continents would be angled in toward each other, and Australia would be up in the corner. The only thing that is even similar is that Antarctica is shown in "normal" proportions rather than stretched across the bottom. [[User:Prometheusmmiv|Prometheusmmiv]] ([[User talk:Prometheusmmiv|talk]]) 11:41, 2 July 2014 (UTC)<br />
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What's the area on the coast between Asteroids (1km+) and Triton? [[Special:Contributions/108.162.222.50|108.162.222.50]] 11:44, 2 July 2014 (UTC)<br />
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(My first contribution here!) About the Earth/water surface issue, I think Randall is talking about planets' surface, and then it counts both earth and water (like if it were a sphere) [[Special:Contributions/173.245.52.173|173.245.52.173]] 12:31, 2 July 2014 (UTC)</div>173.245.52.173