Wikipedia:Reference desk/Archives/Science/2016 August 30

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August 30

Simon Ramo, Edward Teller

Were Ramo and Teller friends? Did they work together on any projects?144.35.45.84 (talk) 05:29, 30 August 2016 (UTC)

They served together (with others) on the President's Science Advisory Council:

• Schwartz, Peter (8 February 2012). "The Art of the Long View". Crown Publishing Group. p. 33.

2606:A000:4C0C:E200:75E6:3520:AC3C:BD97 (talk) 06:32, 30 August 2016 (UTC)

President's Science Advisory Committee (not Council), incidentally. Tevildo (talk) 14:25, 30 August 2016 (UTC)

@Tevildo: Would it be acceptable to add names from that source to the article, even though the source got the name of the 'council' wrong? Such as: Simon Ramo, Edward Teller, Edwin Land, Dr. William Baker, Charles Townes, et al? 2606:A000:4C0C:E200:5121:5CA3:CCCC:2372 (talk) 18:30, 30 August 2016 (UTC)

Of course, if the source is reliable (see WP:RS). Peter Schwartz isn't really an historian, but he can probably be trusted for simple factual information; it might be an idea to double-check with the Committee's official records, though. Does he cite any primary sources for the information in his book? Tevildo (talk) 19:32, 30 August 2016 (UTC)

Medical advice needed

The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

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I have a medical problem. Should I see a doctor? Please advise... :) --Guy Macon (talk) 05:58, 30 August 2016 (UTC)

I recommend Dr. WebMD. clpo13_(talk) 06:07, 30 August 2016 (UTC)

No good. At the bottom of the WebMD page it says "WebMD does not provide medical advice, diagnosis or treatment." Scott Adams (creator of Dilbert) says "Don't take medical advice from cartoonists", and a random stranger on the Internet once told me "Don't follow medical advice that you got from some random stranger on the Internet". I really am thinking that "ask a doctor" is the best answer here. --Guy Macon (talk) 06:46, 30 August 2016 (UTC)

Depends what kind of doctor. DMacks (talk) 06:56, 30 August 2016 (UTC)

The correct answer: "yes" and "no" (Should I see a doctor? / Please advise) 2606:A000:4C0C:E200:E178:E0C9:CBA8:E6CF (talk) 07:06, 30 August 2016 (UTC)

You could always try Dr. Vinny Boombotz. He did wonders for Rodney Dangerfield. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:04, 30 August 2016 (UTC)

If you decide to see a doctor when you do not actually need one, you end up with an unnecessary bill. If you decide not to see a doctor and it turns out that you did need to, you (possibly) end up dead. Your choice. Wymspen (talk) 11:14, 30 August 2016 (UTC)

In the United States, it is not necessary to see a medical doctor (a person with an MD degree) for every medical problem. There are many services that provide professional and respectable medical treatment without a medical doctor. They sometimes uses registered nurses, who are more than capable of handling "do I have the flu" cases. They sometimes use physician assistants who can do just about everything except write certain prescriptions. Our local drug store has a physician assistant office that you can visit for a flat fee of $25. She (it is almost always a woman staffing the office) can diagnose and treat most medical problems. In my opinion, too many people go to the emergency room, where the bill will be hundreds of dollars just to walk through the door, for minor problems. Then, they complain that medical care is too expensive. If they made decisions with their brain instead of their ass, they might try to get better care for much less. 209.149.113.4 (talk) 12:10, 30 August 2016 (UTC)

Nonetheless, they are seeing a professional rather than depending on anonymous internet users. And if they're uncertain what ails them, the emergency room is an option. Self-diagnosis is risky. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:31, 30 August 2016 (UTC)

When I was young and had a bad earache and the doctor just seemed to be making it worse my parents took me around to the local witch doctor and he fixed it no time flat. So go on, take the advice of me - some random person on the web, go to a witch doctor ;-) Dmcq (talk) 13:01, 30 August 2016 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Climate change,lightning

Of course, the fact that 323 reindeer were killed by lightning recently does not show that lightning will become more common as global warming happens. But it made wonder what scientists think will happen with lightning as global warming happens. Will lightning strikes get bigger, more frequent, or smaller, less frequent or what? I didn't see anything on it in Wikipedia. Thanks144.35.45.79 (talk) 16:09, 30 August 2016 (UTC)

Lightning, especially in summer, is commonly caused by large powerful clouds, composed of moist air driven by heat. Many models of global warming might not show such a huge rise in temperature as the simple term "warming" suggests, but they do predict a large increase in this moist air. So I would expect () lightning storms to increase. Of course the particular local effects will vary depending on your type of climate: maritime vs. continental (i.e. moist vs. dry). It's the maritime climates, or areas now bordering on them which may shift to become more maritime-like, that will see the storm increases. Andy Dingley (talk) 17:17, 30 August 2016 (UTC)

This may be of interest. This too. --Jayron32 17:53, 30 August 2016 (UTC)

inclination of moon

Is the inclination of the moon to the ecliptic plane constant?Azmain apro (talk) 18:35, 30 August 2016 (UTC)

See Orbit of the Moon § Inclination for the answer; return here if you have further questions or need clarification. 2606:A000:4C0C:E200:5121:5CA3:CCCC:2372 (talk) 18:44, 30 August 2016 (UTC)

hello.I asked a question earlier that Is the inclination of the moon to the ecliptic plane constant?I was suggested to visit the wiki page,but I didn't find it sufficient.Can you help me on this subject?Azmain apro (talk) 18:53, 30 August 2016 (UTC)

That's because it is a nuanced answer. It's there in the explanation. The orbital plane undergoes precession as noted in the article you were directed to. However, because the precession of the orbital plane is exactly matched by the precession of the rotational axis of the moon, the angle remains constant with respect to the Earth, but not with respect to the stars (see sidereal time). This is one of Cassini's laws, #2 to be precise, and thus has been well known since the lat 17th century. Things get complicated only because one must carefully define one's reference frame when asking about the motion of objects. --Jayron32 19:02, 30 August 2016 (UTC)

The Moon's inclination to the ecliptic varies slightly in both amount and direction. The inclination varies by approximately 0.15° over a period of 173 days, from 5.295° to 4.995°. The direction of its tilt precesses westward in an 18.6-year cycle called the "nutation period." ChrisMentrek (talk) 19:05, 30 August 2016 (UTC)

Note that the reference frame specified in the question is the ecliptic plane. 2606:A000:4C0C:E200:5121:5CA3:CCCC:2372 (talk) 19:16, 30 August 2016 (UTC)

@ChrisMentrek You should avoid using the 'ref' tag in the sections of the ref desk pages because it "breaks" the formatting, by putting the reference at the bottom of the page, instead of the bottom of the section. There is a alternative tag which doesn't "exit" the section, but I can't find it at the moment so I've just removed the offending tag. Vespine (talk) 01:47, 31 August 2016 (UTC)

I've reverted you as there's no harm in using the ref tag in talk pages including the reference desk. And I'm not aware of any alternative tag. Are you sure you're not thinking of {{Reflist-talk}} which ideally should be added to any section on talk pages where the <ref> tags are used? If it isn't added a section will automatically appear on the bottom of the page. But the best solution IMO is to add the reflist-talk yourself or leave someone else do it rather than removing ref tags. It's easier to add the template than it is to find out where the ref tags were and add them back. Having the references at the bottom of the page isn't ideal as it can be confusing, but it doesn't preventing editing and jumping forward and back from the references still works. Nil Einne (talk) 05:09, 31 August 2016 (UTC)

References

Does Venus have spiraling storms ?

...similar to hurricanes and tornadoes on Earth, or the Great Red Spot on Jupiter and Great Blue Spot on Neptune. Venus certainly seems to have the heat energy, from sunlight, to drive such storms. Does the lack of an ocean prevent formation ? [1] does say:

'Previous observations have revealed a vast rotating vortex of clouds with a "double-eye" feature at Venus' north pole. Researchers have now found evidence for similar features at the south pole, but these rotate slightly faster.'

So, is this how heat on the surface dissipates into space ? StuRat (talk) 21:33, 30 August 2016 (UTC)

Ultimately heat on the surface dissipates to space through infrared radiation, same as Earth (or any other planet). Shock Brigade Harvester Boris (talk) 02:13, 31 August 2016 (UTC)

That process has to be extremely slow on a planet with a thick, opaque atmosphere, as the infrared can only penetrate a short distance at a time. Therefore, I have to assume that some sort of convection occurs, to move the heat from the surface to the upper atmosphere, where it can then radiate off into space. That convection usually leads to spiral storms, hence the Q. StuRat (talk) 12:57, 31 August 2016 (UTC)

Venus rotates very slowly (243 days!), hence Coriolis forces, which would lead to the development of spiral storms, are much smaller than on Earth (1 day) or Jupiter (10 hours). See also Atmosphere_of_Venus#Circulation. --Wrongfilter (talk) 13:19, 31 August 2016 (UTC)

I see. So how exactly does convection occur, in the absence of much planetary rotation ? Or does it not occur much at all, being a prime reason why the surface of Venus remains so hot ? StuRat (talk) 14:27, 31 August 2016 (UTC)

Couple of points: (1) Convection per se is due to buoyancy, not rotation. Put a pot of water on your stove and turn on the heat. There will be convection in the water even though you're not spinning the pot around. (2) Regarding infrared radiation, it's true that the infrared penetrates only a short distance from the surface. By Kirchhoff's law of thermal radiation a substance that absorbs thermal radiation also emits it. So the heat absorbed by this thin layer is then emitted both upward and downward by infrared radiation, some of which is absorbed at a yet-higher level. This higher level in turn emits both upward and down, and so on through successively higher levels until the IR can escape to space. Again, the process is essentially the same on Earth: our effective level of emission is an altitude of around 5 km, not the surface. Shock Brigade Harvester Boris (talk) 15:01, 31 August 2016 (UTC)

On Earth, regular convection doesn't seem to provide sufficient cooling, in summer, so that heat builds up in the oceans, until hurricanes/cyclones increase the efficiency of the heat transfer into space and cool the area down. The lack of such a "relief valve" on Venus might go a long way to explain the high surface temps. StuRat (talk) 15:14, 31 August 2016 (UTC)

Convection occurs whenever the temperature differences exceed the local lapse rate, leading to a convective instability. On Earth, the lapse rate is generally 5-10 °C / km of altitude. For temperature differences less than this, adiabatic cooling is sufficiently strong to prevent convective overturning. As discussed at atmosphere of Venus, Venus does have significant convection, with upwelling at the equator and on the day side of planet and downwelling near the poles and on the night side. Because the planet rotates so slowly, this doesn't tend to generate cyclonic storms, due to the lack of a significant Coriolis effect. However, one does have storms on Venus (including lightning), though with the odd feature that the sulfuric acid rain always evaporates before it reaches the ground (virga) due to the extreme surface temperatures. As a heat transfer mechanism on Earth, convection does matter, but it is a relatively small component of the total energy budget (10-15% is my recollection). For Earth, most of the heat transfer from the surface to the atmosphere (~75%) is due to infrared radiation. I'd imagine that radiation is an even larger fraction of the heat transfer budget on Venus. The reason Venus is so hot, is because of it's extreme greenhouse effect. Imagining increased convection could cool Venus some, but you'd need far, far more than a few hurricanes to counter the extreme greenhouse effect and make much of a difference in the planet's surface temperature. Dragons flight (talk) 09:45, 1 September 2016 (UTC)

Yes, this is why I'm surprised it doesn't have something similar to the Great Red Spot, or several such large, permanent vortex storms, near the equator. I thought the Coriolis effect was minor, and that there were other factors leading to rotation, although I would expect the direction of rotation to be more random on Venus. StuRat (talk) 15:23, 1 September 2016 (UTC)

Because the planet rotates so slowly, this doesn't tend to generate cyclonic storms, due to the lack of a significant Coriolis effect. The Great Red Spot is a cyclonic storm. The Coriolis force is what turns straight air movements into cyclic air movements. Without it, there is no reason for cyclonic storms to form. --Stephan Schulz (talk) 15:41, 1 September 2016 (UTC)

Then why do dual, permanent, cyclonic storms exist at both poles of Venus ? I don't believe it's correct to say that the Coroilis effect is the only reason why storms rotate. For example, water running down a drain wants to rotate, and at that scale I don't believe Coroilis forces are significant. What I am missing is why the spiral storms on Venus exist ONLY at the poles. StuRat (talk) 02:29, 2 September 2016 (UTC)

• Of course, a lot of heat doesn't dissipate into space, hence why the surface is hot enough to melt lead. Fgf10 (talk) 07:57, 31 August 2016 (UTC)

• If the temperature has reached an equilibrium point, then all heat produced on the planet (by sunlight, radioactive decay, and tidal forces with the Sun) must now leave the planet somehow, to maintain that temp. StuRat (talk) 12:57, 31 August 2016 (UTC)

Of course, the heat eventually escapes (or we'd be violating thermodynamics). However, my point was correct, the atmosphere stops immediate radiate dissipation of hear, reflecting it back to the surface and heating it (by well over 400°, in the case of Venus). That link has a nice detailed explanation, I'm not going to copy all of that here. Fgf10 (talk) 15:51, 31 August 2016 (UTC)

I did some more research, and here's a pic of the Venus North pole dual vortex, which is basically two permanent hurricanes spinning in the same direction: [2]. There appears to be the same thing at the south pole, but our images there aren't as good. StuRat (talk) 15:44, 1 September 2016 (UTC)