Wikipedia:Reference desk/Archives/Science/2022 February 27

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February 27[edit]

upper and downer drugs at the same time[edit]

I just read something about Anthony Eden taking Drinamyl, a combination of amphetamine and barbiturate. Why would those two drugs get combined, speed and a depressant? Do they cancel each other out? What was it used for? The article says it is discontinued now, probably for good reason. But I wonder what it was used for in the first place. 2601:648:8202:350:0:0:0:C115 (talk) 01:07, 27 February 2022 (UTC)[reply]

The Desbutal (a similar drug) article explains why this makes sense (or made sense back then) medically. The effect of combining substances is not algebraic, you are not combining 1 and -1. You can combine antagonizing substances to try to get rid of unwanted side-effects.
In both cases, Desbutal and Drinamyl, they were highly abused and are no longer manufactured.--Bumptump (talk) 01:42, 27 February 2022 (UTC)[reply]
Speedball (drug) has some discussion on this. Things that seem opposites don't necessarily cancel each other out; for example sugar and salt do not simply neutralize each other out in a dish. 85.76.97.34 (talk) 15:27, 27 February 2022 (UTC)[reply]
More legal Caffeinated alcoholic drinks also exist, i.e. espresso martini, formerly Four Loko etc. with a similar mix of a stimulant and a depressant. The Wikipedia article lists some reasons why people would consume them. --Jayron32 13:00, 28 February 2022 (UTC)[reply]
They affect different parts of the central nervous system: dopamine release (amphetamine) and GABA receptors (barbiturate). Both drugs have wanted (pleasant) and unwanted effects (amphetamines: nervousness,... barbiturates: drowsiness, tiredness). They both lessen some of the unwanted effects of the other, without cancelling the wanted effects. Antipsychotics on the other hand block dopamine pathways, so combining them with amphetamines would make little sense, they would reduce or cancel all the effects. Prevalence 18:32, 3 March 2022 (UTC)[reply]

What's the proof that we can't see Far side of the Moon from Earth?[edit]

Moon is always white, spherical and spinning on its own axis, then what's the proof that we can't see Far side of the Moon from Earth? Rizosome (talk) 07:37, 27 February 2022 (UTC)[reply]

Well, the Moon has a landscape, with craters, mountains and large plains, it is neither perfectly white nor perfectly spherical. We always see the same landscape, the same side of the Moon (a bit more than half the Moon's entire surface due to libration) and noone had ever seen the other side before spacecraft went around the Moon starting in 1959. Is that proof enough? --Wrongfilter (talk) 08:12, 27 February 2022 (UTC)[reply]
Incidentally, "proof" is not quite the right term, "empirical fact" is better. --Wrongfilter (talk) 08:14, 27 February 2022 (UTC)[reply]
(edit conflict) What is the proof we can see the near side of the Moon from Earth? By definition, the far side of any object is the part you cannot see. If you accept that the Moon is far away from us and that the shape of its surface is basically a sphere, the two sides (the side that can be seen and the side that cannot be seen) are hemispheres. The point is that they remain (almost) stationary, so when we look at the moon we always see the same familiar features, the Mare Tranquillitatis, the Mare Fecunditatis, the crater Copernicus, and so on. What is the proof that we always see the same face? It has been obtained by observation. By looking up and seeing that the Moon looks just like yesterday, like last year, like on old paintings and like described by the ancients. Using telescopes astronomers can measure its speed of rotation very precisely, and it matches the speed with which the Moon circles the Earth. Since the latter varies somewhat in time while the two speeds keep matching, the only plausible explanation of this observed match is tidal locking.  --Lambiam 08:15, 27 February 2022 (UTC)[reply]
The OP's question is rather silly on the face of it, unless by "proof" he actually means "explanation". --←Baseball Bugs What's up, Doc? carrots→ 09:02, 27 February 2022 (UTC)[reply]
What is the point of that comment? Do you have anything substantial to contribute to the question? --Wrongfilter (talk) 09:21, 27 February 2022 (UTC)[reply]
Thanks for the joke. I'm trying to establish what the OP is really asking. --←Baseball Bugs What's up, Doc? carrots→ 18:03, 27 February 2022 (UTC)[reply]
Possibly you wanted to ask some slightly different question, because the anwer for precisely this one is: there is no formal proof we can't (similarly to the lack of a proof man can't see the back of own head), but publicly available sources do not report on any such observations. --CiaPan (talk) 09:45, 27 February 2022 (UTC)[reply]

The moon is tidally locked as it orbits the earth, so we can see only one side of it. 2601:648:8202:350:0:0:0:C115 (talk) 10:10, 27 February 2022 (UTC)[reply]

The other way round: We can only see one side of the Moon, so we know that it is tidally locked. --Wrongfilter (talk) 16:33, 27 February 2022 (UTC)[reply]
Any proof will always be in terms of either postulates or what you're willing to accept without further examination. In this particular case, if you sketch out the system of a circle (you can project the system onto the plane) rotating around a point, then note that the circle is rotating around its own axis with the same angular velocity as its rotation around the point, it should not be difficult to demonstrate that the intersection of the line segment from the centre of the circle to the point with the circumferance of the circle does not change with time. — Preceding unsigned comment added by 37.165.69.92 (talk) 17:09, 27 February 2022 (UTC)[reply]
That is true if the Moon is tidally locked. But does it have to be locked? I think not – as long as the system is relatively undisturbed, yes, it's highly likely, but ultimately it depends on the history of the system. --Wrongfilter (talk) 17:14, 27 February 2022 (UTC)[reply]
Sketch out the system, then note that "the proof that we can't see the farside" requires that the two angular velocities be identical. Just why that might or might not be true (observation, predicted tidal locking or divine intervention) is a separate "question. 37.165.69.92 (talk) 17:43, 27 February 2022 (UTC)[reply]
It seems to me that there is nothing here that adds to the first two responses.  --Lambiam 18:17, 27 February 2022 (UTC)[reply]
  • What's the "proof" that you can't see your own face except via a camera or a special arrangement of mirrors? -- Jack of Oz [pleasantries] 19:22, 27 February 2022 (UTC)[reply]
(on original topic) To me it was always just sufficient to note that it's not properly enough lit to see it. It can face the Earth, but we cannot see it. --Ouro (blah blah) 03:47, 28 February 2022 (UTC) No wait that's just not true! It doesn't really rotate. Stupid. --Ouro (blah blah) 03:48, 28 February 2022 (UTC)[reply]

It's worth noting that the Moon is not white. It's actually much closer to black, with an albedo similar to coal, but when it's lit by the Sun against the backdrop of space and viewed with dark adapted eyes it looks kind of pale. nagualdesign 03:58, 28 February 2022 (UTC)[reply]

  • Outside of solipsism, the proof that we can't see the far side of the moon from Earth is that we don't. It's an observation anyone with eyes can make. --Jayron32 12:57, 28 February 2022 (UTC)[reply]
The first photographs of the dark side were taken in 1959 by the Russian spacecraft Luna 3, which enabled a map of the features to be made. The landscape is quite different from the features we can see from Earth. So we know what is there and we know that we can't see it. See also How the Soviet Union Snapped the First Picture of the Far Side of the Moon and What’s On The Far Side Of The Moon?. Alansplodge (talk) 14:37, 28 February 2022 (UTC)[reply]
This is true, but given the vagueness of the question, I took the OP's meaning to be "When we look at the moon in the sky, where is the proof that we don't see the other side." To which the answer is "You look at it, and you never see the other side". Perhaps the OP meant something quite different, but we all do the best we can given what we can interpret. --Jayron32 15:47, 28 February 2022 (UTC)[reply]
There is no "dark side". Or rather, there are an infinite number of "dark sides". Far side. Far side. Not dark side. --jpgordon𝄢𝄆𝄐𝄇 15:58, 28 February 2022 (UTC)[reply]
There is no dark side of the moon, as a matter of fact, it's all dark. --Jayron32 17:02, 28 February 2022 (UTC)[reply]
From our article Far side of the Moon: ""The hemisphere is sometimes called the "dark side of the Moon", where "dark" means "unknown" instead of "lacking sunlight"". --Modocc (talk) 17:57, 28 February 2022 (UTC)[reply]
As with the old-fashioned expression, "Darkest Africa." --←Baseball Bugs What's up, Doc? carrots→ 19:50, 28 February 2022 (UTC)[reply]
Or less politically incorrect: the Dark Ages. Martin of Sheffield (talk) 21:10, 28 February 2022 (UTC)[reply]
Darkest Africa did not refer to the people. --←Baseball Bugs What's up, Doc? carrots→ 21:48, 28 February 2022 (UTC)[reply]
Unfortunately it was sometimes seen as a play on words, and really ought therefore to be avoided altogether today. Martin of Sheffield (talk) 22:56, 28 February 2022 (UTC)[reply]
I'm sure it could be seen that way. And it's obsolete. But it's another example of "dark" as "mysterious". --←Baseball Bugs What's up, Doc? carrots→ 02:28, 1 March 2022 (UTC)[reply]
It's worth pointing out that Rizo's initial question was, in fact, about the "far side" of the moon, not the "dark side"[1] --←Baseball Bugs What's up, Doc? carrots→ 06:14, 1 March 2022 (UTC)[reply]
While inside of a solipsist, it's too dark to read. Just like on the Moon. --47.155.96.47 (talk) 18:18, 28 February 2022 (UTC)[reply]
The Soviet Union had communication with Luna 3 between 4 and 22 October 1959. The far (as opposed to "dark" side of the moon ([2] at 2:49)) was fully illuminated by the sun at 12:30 GMT on 2 October. The sun moves across the sky thirty times slower than it does here. Photography began exactly 4 days 15 hours later and was completed within 40 minutes. 2A02:C7F:F206:A500:44D1:B021:3286:E546 (talk) 11:42, 1 March 2022 (UTC)[reply]