Wikipedia:Reference desk/Archives/Science/2017 March 10

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March 10

Flat Earth Hypothesis is easily proven wrong

How do flat earth people explain the fact that the moon appears upside down when viewed in Australia as compared to viewing in Canada (at the same time)? I like to hear the flat earth scientific explaination. 148.182.26.69 (talk) 02:18, 10 March 2017 (UTC)

Who says it looks upside-down in Australia? ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:21, 10 March 2017 (UTC)

People from the northern hemisphere who go to Australia and look. Matt Deres (talk) 03:30, 10 March 2017 (UTC)

I see what they're getting at. It's all in the way you're looking up at it. And it seems that there is a lot of stuff in Google about how this "proves" the earth is round. I'm not so sure that's definitive. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:37, 10 March 2017 (UTC)

Flat Earthers believe there is an international conspiracy comprised of every national government, every airline employee, major shipping companies, anyone involved in space travel, and the entire population of the southern hemisphere. I would not expect any sort of evidence to sway them. As Jonathan Swift said, "Reasoning will never make a Man correct an ill Opinion, which by Reasoning he never acquired." Someguy1221 (talk) 03:59, 10 March 2017 (UTC)

Ole was driving home and Lena called him on his cell. "Be careful, Ole, dere's some idiot drivin' de wrong way on de expressway!" Ole said, "Dere's not yust one, dere's hundreds of 'em!" ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:33, 10 March 2017 (UTC)

Not just the moon, even the constellation of Orion is upside down. "In ancient Greek mythology, Orion was a legendary hunter. To us in the southern hemisphere, he appears upside-down and is quite easy to recognise." from the website 148.182.26.69 (talk) 05:13, 10 March 2017 (UTC)

They're not upside-down if you're facing south while looking up at them. ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:45, 10 March 2017 (UTC)

Generally speaking, you can't see a northern constellation at all while facing south and standing in the southern hemisphere. A bit more complicated than that, but it's the gist. Someguy1221 (talk) 06:12, 10 March 2017 (UTC)

• Maybe a question for Wikipedia:Reference Desk/Pseudoscience? Tigraan^{Click here to contact me} 09:00, 10 March 2017 (UTC)

Assuming you're standing straight up and down. But here's the thing: if you were to lie/recline back on something so you can see objects in the northern sky, then their orientation is the same as in the Northern Hemisphere. The only reason for the perceived difference is that the guys in the Northern Hemisphere normally, under gravity, are tilted north, while the blokes in Australia looking in the same direction in the sky are typically tilted south. Up is not up. Wnt (talk) 12:17, 10 March 2017 (UTC)

As said by others, this doesn't seem to be a science question but see [1] [2] [3] [4]. There's even videos if you prefer [5] [6] [7] [8]. Nil Einne (talk) 10:21, 10 March 2017 (UTC)

That the moon appears the other way up in Australia does not disprove that the earth is flat. It is just a matter of perspective. If the moon is 45 degrees above the southern horizon in the north and 45 degrees above the northern horizon in Australia then it must be about 3000 miles above the earth and have a diameter of about 25 miles. This has been obvious to people for centuries, it is sad that people nowadays can't work these things out for themselves rather than believing everything the military-industrial complex wanting billions for their rockets pushes at them ;-) Dmcq (talk) 11:46, 10 March 2017 (UTC)

Any fool can look out his window and see that the earth is flat.[9][10] --Guy Macon (talk) 15:55, 10 March 2017 (UTC)

So if i am just slightly north of the equator watching the moon, and i step south, across the equator, when does the moon flip? Greglocock (talk) 17:28, 10 March 2017 (UTC)

Till at least 2025 AD the Moon can be upside down as far north as 20+ km north of central Orlando, parts of Texas and halfway between Shanghai and Taiwan Island. But only for a small fraction of the year once every 18 or 19 years. In reality it might not look that upside down without a plumbbob till hundreds of kilometers further south. When the Moon's overhead as far south as it gets it could appear north side up in the northernmost Australian state capital (Brisbane) but maybe so close to overhead that you couldn't tell. Sagittarian Milky Way (talk) 04:23, 11 March 2017 (UTC)

When you turn your body 180 degrees. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:36, 10 March 2017 (UTC)

If you're that near the Equator, you'll be looking directly overhead to see the Moon. So one can't really define which way is "up" when looking at the Moon, unless also stating which direction you're pointing in. Andy Dingley (talk) 20:29, 10 March 2017 (UTC)

?Directly overhead? how come. Its on the horizon quite oftenGreglocock (talk)

The equator also makes the Moon lie on its side much more than at middle latitudes. Sagittarian Milky Way (talk) 04:23, 11 March 2017 (UTC)

The Moon being north of you relative to the ground in one place and south of you relative to the ground in another is not inherently contradictory with at least some flat-earth theories (i.e. there might be some that suppose some kind of exotic geometry where all bets are off. That seems to be pretty common among the more "educated" or "internet-savvy post-ironic" flat earthers); indeed, if the earth is a plane section and the moon is above it then surely there exists a line segment on the plane section for every angle T such that T is the angle in the planar dimension between every point on that segment and the moon. That is, if you're standing in a ballroom and look up at the chandelier in the center, then walk across the ballroom and look at it again, you'll both have to look in a different direction AND see a different part of the chandelier. 97.93.100.232 (talk) 02:59, 11 March 2017 (UTC)

Actually that is the basis of a contradiction, because you don't see many different parts of the Moon in the North and South - the difference is only what you'd expect for a ball a quarter of a million miles away, whereas (as Dmcq calculated) if you assume the Earth is a plane and the Moon above it, the Moon is only 3000 miles away, which means that observers in different hemispheres should see almost half of a landscape unique from their position. Of course, belief in a Flat Earth lends itself to belief in a Flat Moon that only happens to look like a ball in the sky, in which case you both see exactly the same terrain ... which is again disprovable, but only with some fancy telescopes doubtless owned by compliant geeks who suck up to the Elders of Zion. But there's also the question of why the flat Moon doesn't look like an ellipse from far north and far south, which I'd think could be addressed with some really remarkable handwaving about atmospheric phenomena that distort the view of it (but not the stars behind it). The Flat Earth thing doesn't really hold water; we just have to be careful about using disproofs that only work if you assume the Earth isn't flat. Wnt (talk) 20:22, 11 March 2017 (UTC)

How could time zones exist in-universe? Do Flat Earthers never call an overseas person they trust at sunset and ask whether it's setting now? Sagittarian Milky Way (talk) 21:21, 11 March 2017 (UTC)

Of course flate-earthers can explain time zones. Look at the following video, starting at 3:35. [11] --Guy Macon (talk) 18:04, 13 March 2017 (UTC)

At what height are hill/mountains made from rock?

Mountains in Colorado for example look like they are made from rock but other mountains in other places look like they are made from dirt but are actually made from rock underneath. How do you know if a mountain or large hill is all dirt or has rock underneath? Does it happen at a certain height?--Sara203040 (talk) 03:02, 10 March 2017 (UTC)

It's all rock if you go deep enough. Lower elevations are warm enough for vegetation to grow, which over time Soil accumualtes. Above the Tree line, it's mostly just rock and ice. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:39, 10 March 2017 (UTC)

Actually, beneath that it's turtles all the way down. μηδείς (talk) 03:58, 10 March 2017 (UTC)

For further information, see Turtle Rock. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:35, 10 March 2017 (UTC)

Wikipedia has not one, but at least two articles on mountain building, Mountain formation and Orogeny. It's a complex process, but Wikipedia's articles are a good a place as any to start learning. --Jayron32 03:45, 10 March 2017 (UTC)

Some hills are made of sediment (sand, mud, gravel, probably some loose rocks) rather than solid rock. However, these are particular types of hills, defined by how they were formed rather than just their size. Iapetus (talk) 11:03, 10 March 2017 (UTC)

The depth of the rock bed under topsoil can be mapped using techniques of Reflection seismology if a controlled Seismic source such as a vibrator or explosives is available, or by Ground-penetrating radar which can penetrate up to 15 meters in some soils (or much deeper through ice) at low radio frequencies. A natural indicator of non-porous bedrock is at the level of the Water table where water springs emerge. Blooteuth (talk) 13:48, 10 March 2017 (UTC)

If you are interested in dirt formation in mountains, there are many studies done at the Biltmore estate. It was a barren mass of red clay hills before work was done to get a forest growing again. It now has soil on top of the clay throughout most of the forest. Understanding how the soil was replenished by regrowing the forest helps explain how mountains have dirt below the tree level, but not above it. 209.149.113.5 (talk) 18:13, 10 March 2017 (UTC)

Would a hill 1,500 feet high likely be made from rock or soil?--Sara203040 (talk) 21:34, 12 March 2017 (UTC)

Sour strawberries

I know sucrose is sweet, and dissociation of an acid is sour. But why are most of my store bought strawberries sour? 166.216.159.224 (talk) 15:52, 10 March 2017 (UTC)

The Strawberry article doesn't overtly say, but it's possible they're picked before they're fully ripe. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:15, 10 March 2017 (UTC)

This may be helpful. It should be noted that, depending on where you are located, strawberries are not likely in season. Your IP address geolocates to Michigan; your local season is late may-early june. That means your berries from your store may be shipped in from somewhere else, quite possibly as far away as the other side of the planet (a lot of fruits in the Winter in the U.S. are grown in Chile and shipped to the U.S.) and as such, they are usually picked "underripe" so they don't spoil on the trip. The under-ripe strawberries are treated with ethylene to "redden" the surface, but that doesn't effect the flavor. here is some good information on off-season strawberries. --Jayron32 16:33, 10 March 2017 (UTC)

Do you have a source for the ethylene ripening not changing flavor? Maybe it's different in different fruits. For example Bananas are treated similarly, shipped green then ripened with ethylene. Our ripening article also has some nice info at the top on acidity, sourness and sweetness of fruit. To me, (WP:OR) ripened bananas taste different than green bananas, and I have ripened green bananas at home using the ethylene from ripe bananas - these also change in sweetness and flavor. SemanticMantis (talk) 16:41, 10 March 2017 (UTC)

So amended per [12] Underripe strawberries do not respond to ethylene. Thanks for the correction. Strawberries do not ripen after picking, and looking deeper into sources I cited above, specific breeds of strawberries are grown for long-distance shipping. These breeds are naturally lower in sugar, so taste less sweet and more sour. The lower sugar content results in longer shelf life, but makes them less sweet than breeds grown for local market use. --Jayron32 16:48, 10 March 2017 (UTC)

Ethylenecontrol.com has some detailed info on lots of relevant stuff, thanks! SemanticMantis (talk) 21:27, 10 March 2017 (UTC)

Also note that strawberries, even when fully ripe, aren't all that sweet. [13] (switch to 100 g serving), lists only 5 grams of sugar per 100 gram serving. Compare that to honey: [14], which has 82 grams of sugar per 100 grams, or a mango, which has 15 grams of sugar per 100 g serving: [15]. Many people add some form of sugar, such as sugar added to whipped cream, to their strawberries. StuRat (talk) 21:34, 10 March 2017 (UTC)

Good point. I like them just the way they are, personally, but most (that I've seen anyway) do seem to sweeten them before eating. Earl of Arundel (talk) 22:32, 10 March 2017 (UTC)