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November 20

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Is Roy Spencer (scientist) a climatologist or meteorologist? Or both?

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This question is about Roy Spencer (scientist). I know that our article on Roy Spencer (scientist) says that he's meteorologist. However, I sometimes see people refer to him as a climatologist. My question is whether it's accurate to refer to Spencer as a climatologist or meteorologist? Or both? A Quest For Knowledge (talk) 00:21, 20 November 2018 (UTC)[reply]

On this page he identifies himself (at the top left) as a climatologist, but says his Ph.D. is in meteorology. --76.69.46.228 (talk) 06:16, 20 November 2018 (UTC)[reply]
Whether to list one's education or the job they do is always a judgement call. I am currently working with another engineer on a project. His business card says "engineer". Every job he has worked at in the last ten years+ had "engineer" as the job title, and we are designing a product, not doing basic research. His degree? PhD. in Physics. --Guy Macon (talk) 07:44, 20 November 2018 (UTC)[reply]

Climatologists altering their results for financial gain

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Let's say a climate change denier claims that climatologists are altering their results to get them better funding and job security. What's a good rebuttal? A Quest For Knowledge (talk) 00:30, 20 November 2018 (UTC)[reply]

How about To get a PhD in climate one must be intelligent and dedicate years to education and slave-wages as a postdoc. If they wanted money and willing to lie, why didn't they become a hedge fund manager in the first place? Jim1138 talk 01:00, 20 November 2018 (UTC)[reply]
Not a good rebuttal, since presumably crystal-healing schools require their students to devote a lot of time to studying crystal-healing.
The real rebuttal is "where is your proof?". See burden of proof. Notice also that extraordinary claims require extraordinary evidence: claiming one "climatologist" is corrupt, falsified data etc. to get a better position can be proven by article retractations, emails etc. from that one person, whereas the claim that all (or an overwhelming majority of) "climatologists" are corrupt needs much more. (Scientists getting money for their funding is not proof of a conspiracy.) TigraanClick here to contact me 12:54, 20 November 2018 (UTC)[reply]
since presumably crystal-healing schools require their students to devote a lot of time to studying crystal-healing - you may presume, but on what is that presumption based? Most pseudo-sciences are simple - that's part of their attraction. But the rest of your comment is good. Also note that increasingly methods and data are public, and there are many statistical methods to detect doctored data. --Stephan Schulz (talk) 15:29, 20 November 2018 (UTC)[reply]
OK, the crystal healing curriculum might be a bad example. My point is that difficulty/length of study does not qualify a field to be a real thing. A better example might be alchemy, whose theoretical bases are wholly pseudoscientific (even if it gave the first actual chemists some really decent bases of experimental work). It was not easy being recognized as a prominent alchemist in (say) the 15th century; it does not mean it was any less of a pseudoscience that today's crystal healers. TigraanClick here to contact me 17:42, 20 November 2018 (UTC)[reply]
Just say "citation needed". And then ask for reliable sources when they quote Fox News. --jpgordon𝄢𝄆 𝄐𝄇 18:30, 20 November 2018 (UTC)[reply]
Anyone saying this is not going to be convinced to change their mind by a direct counterargument. They never saw a clearly documented instance of a credentialed climatologist being financially influenced to publish fake results, because no such instances exist. They don't believe in anthropogenic climate change for other reasons, often deeply-seated philosophical beliefs like the belief that economic growth is always good with no downsides. Things like "crooked climatologists" are believed in to reassure oneself well as to provide simpler justifications attributed to external causes. ("I'm open-minded, but those scientists are faking it for money!") To have any success in changing minds, you first need to get to the root cause of their belief. Try a Web search for something like "how to change minds on climate change", as people have written better explanations of this than I can. But be aware nothing is guaranteed to work. --47.146.63.87 (talk) 07:07, 23 November 2018 (UTC)[reply]
Well I have seen a couple support climate change denial for religious reasons. For instance Roy Spencer mentioned in the immediate previous discussion signed the Evangelical Declaration on Global Warming . Whether he knows he is cooking his results I don't know, people have a great capacity for deceiving themselves. Dmcq (talk) 14:29, 23 November 2018 (UTC)[reply]
@Tigraan and Jpgordon: Here is the proof that was given: Judith Curry's resignation over 'the CRAZINESS in the field of climate science.' A Quest For Knowledge (talk) 11:36, 1 December 2018 (UTC)[reply]
I read it, and... Wut? That article says zilch about climatology-specific problems. Publish or perish etc. is the same in every domain. Yes, it means you should not take a single paper as gospel just because it's peer reviewed; but that does not mean you can doubt all of science.
I just learned of Judith Curry's existence but my OR analysis (based on that link + the WP article) is that she got drunk on internet fame at the same moment as becoming a pariah among climate scientists because she greatly exaggerated the uncertainty of the models. She says Once you detach from the academic mindset, publishing on the internet makes much more sense, and the peer review you can get on a technical blog is much more extensive. (Volume is not all that matters, else politicians would get policy advice from online newspapers comment sections.) But peer review is not really the point; provoking people to think in new ways about something is really the point. In other words, science as process, rather than a collection of decreed ‘truths.’ (That process is vulgarization, not science. Scientific truths are decrees in the same sense as newspapers reporting on events are "creating" the event - there exists an underlying, unescapable reality.)
Also: defending some minority position (in any academic domain) is OK and will usually not make you a pariah if you have supporting arguments; defending something batshit crazy will. Saying "I believe models to be more inaccurate than the general consensus, so we do not know how much exactly the temperature will rise due to anthropogenic climate change" is the equivalent of defending non-asteroid causes for dinosaur extinction; saying "we have no fucking clue what will happen at all" is the equivalent of asserting dinosaurs never existed. TigraanClick here to contact me 18:48, 1 December 2018 (UTC)[reply]

The new BFR design which is counter-intuitive

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Elon Musk mentioned recently that he has made changes to BFR design which are counterintuitive and radical in nature. What are they? — Preceding unsigned comment added by Vinodjetley (talkcontribs) 00:56, 20 November 2018 (UTC)[reply]

I think even if anyone working for SpaceX was active on this board, they'd know they couldn't just randomly reveal company secrets on the RD [1] [2]. And even if people who can like Elon Musk happen to hang out here, I think you're still better asking them on Twitter since they've never been public about their involvement here. Nil Einne (talk) 01:34, 20 November 2018 (UTC)[reply]
Musk? On Twitter? He probably announced that it also turns into a submarine. Made of chocolate. Which fights crime on its days off. But not securities fraud or, you know, it might have to arrest his own twitter account. Andy Dingley (talk) 02:08, 20 November 2018 (UTC)[reply]

NASA Blended Wing Body Projected Development

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Has NASA given a time frame for when they expect to conclude BWB airframe research? Is the project simply ongoing with an indefiante completion date? Puzzledvegetable (talk) 03:23, 20 November 2018 (UTC)[reply]

The X-48 program has already concluded, but the blended-wing-body concept is among the proposals that NASA is looking at funding for its next sub-sonic X-plane. If the blended-wing-body concept is selected, the goal is to begin implementation in 2020, have a first flight in 2026, and commercialization by 2035. See https://www.nasa.gov/aero/industry-provides-nasa-with-ideas-for-next-x-plane. --Ahecht (TALK
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White acacia (not the tree)

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What is/was the chemical warfare agent known in Russia by the codename "White Acacia"? Is it related in any way to the Novichok nerve gases such as the one used to poison Sergei Skripal? 2601:646:8A00:A0B3:682D:64AF:511E:C96C (talk) 05:10, 20 November 2018 (UTC)[reply]

I didn't see find 'acacia' in this, though searching in pdfs seems to be a deprecated feature nowadays. I tried a web search to see any discussion of it and found this question before anything else. We'll need a cite for where you encountered the term to progress further, I think. Wnt (talk) 12:54, 20 November 2018 (UTC)[reply]

Pulp ballistics

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I've already asked this question, but User:Baseball Bugs removed it in blatant violation of reference desk policy: In that infamous "Do you speak English, motherf**ker" scene, the way Jackson and Travolta are positioned, wouldn't they have shot each other as well as Whaley? 2601:646:8A00:A0B3:682D:64AF:511E:C96C (talk) 05:13, 20 November 2018 (UTC)[reply]

Where and when did I delete that question? I can't find it. ←Baseball Bugs What's up, Doc? carrots14:52, 20 November 2018 (UTC)[reply]
(The scene in question is presumably this one.) Basically, no. They're both clearly pointing their guns downward; it looks to me like they're not standing opposite one another (more like 7 o'clock and 11 o'clock if dying guy is the centre of the clockface); and they're both expert assassins, so they probably a) will hit dying guy, and b) will know whether there's a risk of a bullet passing right through dying guy and hitting the other assassin. HenryFlower 11:06, 20 November 2018 (UTC)[reply]
Thanks! 2601:646:8A00:A0B3:682D:64AF:511E:C96C (talk) 11:11, 20 November 2018 (UTC)[reply]
Resolved

Artillery question

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When firing indirectly, what is considered a reasonable number of shots to (1) bracket the target, and (2) to score a direct hit on the target? 2601:646:8A00:A0B3:682D:64AF:511E:C96C (talk) 05:14, 20 November 2018 (UTC)[reply]

Does https://www.globalsecurity.org/military/library/policy/army/fm/6-30/f630_6.htm help answer your question? --Guy Macon (talk) 07:49, 20 November 2018 (UTC)[reply]
Thanks! So, with the hasty bracketing technique (which is the one I was referring to), 2 rounds to bracket and then fire for effect? 2601:646:8A00:A0B3:682D:64AF:511E:C96C (talk) 11:22, 20 November 2018 (UTC)[reply]
You are close, but it is a little more complicated than that. Take a look at https://hdl.handle.net/2027/uc1.d0002402790 ( also at https://books.google.com/books/about/The_field_artillery_observer.html?id=A0tRAQAAMAAJ ) -- especially chapter 5. --Guy Macon (talk) 19:44, 20 November 2018 (UTC)[reply]
Its not measured in number of volleys but in a timeframe and the artillery units just fire out as often as they can in that timeframe. Artillery is mostly used against soft targets and because its assumed that after the first shells impact an area, targets that where not hit directly seek cover in a few seconds, so additional volleys become very ineffective. --Kharon (talk) 05:54, 21 November 2018 (UTC)[reply]

Anyone could help to create Consumption_of_alcohol_in_space?

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Thank you!Ericdec85 (talk) 05:41, 20 November 2018 (UTC)[reply]

Why? --Jayron32 12:43, 20 November 2018 (UTC)[reply]
Since there is a Sex in space article, we could also have a Drinking in space article. The topic might have had enough notable discussions for having it included, maybe not as an article but as a section. The Effect of spaceflight on the human body article could include a section about it.--Doroletho (talk) 21:48, 20 November 2018 (UTC)[reply]
Is there reliiable sources on it? Otherwise we might as well have articles on gambling in space and driving fast cars dangerously in space. Dmcq (talk) 00:02, 21 November 2018 (UTC)[reply]
If anyone knows that, its certainly the russians. Unfortunately they are also known to be pretty immune aka not affected and thus unfortunately there is no information worth writing an article about. Check the russian Wikipedia to make shure!! --Kharon (talk) 06:05, 21 November 2018 (UTC)[reply]
Well Elon Musk has got his Tesla Roadster in space now with Starman driving it. Seems pretty dangerous to me so all we need is a reliable source on its dangers ;-) Dmcq (talk) 14:00, 21 November 2018 (UTC)[reply]
I can't help but feel like we've answered this question many times before... I seem to remember linking to this famous 2006 interview with Dr. Charles T. Bourland, who held advanced degrees in food science and technology and helped run the space food research program in the Space and Life Sciences Directorate during the Skylab through the Shuttle eras. "An interesting side story up there is when you open this wine—I don’t know if you’ve been on a zero-G plane. Whatever you open, it just immediately saturates the cabin with that odor, whatever it is. As soon as you open the wine, you see people grabbing for their barf bags."
And here is a surprisingly well-researched 2015 news article from NBC: Alcohol in space?
Nimur (talk) 21:34, 21 November 2018 (UTC)[reply]

Electrochemical gases compressor

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Does the type of compressor mentioned at electrochemical hydrogen compressor work for other gases like oxygene, nitrogen, chlorine, helium, etc? Thanks! (I thought previously that RDS was protected and posted the question on refdesk talk.)--109.166.206.2 (talk) 16:13, 20 November 2018 (UTC)[reply]

What is the condition for working with any type of gas, including monoatomic gases like helium, argone, etc?--109.166.206.2 (talk) 16:18, 20 November 2018 (UTC)[reply]

The electrochemical hydrogen compressor is contingent upon having an ionizable gas: in this case the oxidation of the hydrogen to hydrogen ions is a vital part of the process hypothetically any substance is oxidizable with sufficient energy. Practically, you aren't going to make O+ ions. Oxygen can be reduced to O-2, so there's an ion that one would think would work, but then that will react with the water in the electrolyte solution to give you OH- ions, which may create its own issues. Hydrogen is somewhat unique here as a gas whose most stable ion is a positive ion which is also water soluble. All of those are potential complicating factors. Hydrogen, chemically speaking, is so weird that chemists frequently place it in its own category (i.e. it isn't a Halogen, or an Alkali Metal, or something like that). For that reason, one can often not treat hydrogen chemistry as analogous to other sorts of chemistry.--Jayron32 16:43, 20 November 2018 (UTC)[reply]
I see that the electrochemical compressor contains an important component, namely a proton exchange membrane in the case of hydrogen. How can this requirement be achieved for other gases? I see that there is an article anion exchange membrane.--109.166.206.2 (talk) 11:48, 26 November 2018 (UTC)[reply]
I also see the article(s) re helium compounds, including ionic compounds which can be used for a helium cation exchange membrane.--109.166.206.2 (talk) 12:08, 26 November 2018 (UTC)[reply]

Latest Polio statistics

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I am updating my Polio lecture. I believe there were 22 new cases of Paralytic Polio in 2017. How many new cases of Paralytic Polio have there been so for in 2018? It's not clear from your website. Thanks, Tim. 78.147.21.202 (talk) 19:45, 20 November 2018 (UTC)[reply]

According to [3], an initiative of the WHO, so far there were 27 cases detected in 2018.--Doroletho (talk) 21:43, 20 November 2018 (UTC)[reply]
Poliomyelitis_eradication#2018 list 27 wild cases and 85 vaccine-derived. Rmhermen (talk) 22:08, 21 November 2018 (UTC)[reply]
Note this does not include acute flaccid myelitis, which is suspected to be caused by a not very closely related enterovirus. Wnt (talk) 05:04, 24 November 2018 (UTC)[reply]

Are there any ranges where a Boeing 777X might have worse fuel economy than early intercontinental ballistic spaceliners?

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Designing and manufacturing such a craft now might be way more expensive so it won't happen any time soon but would the fuel necessarily cost more per passenger with such low cruising drag? Drag in the atmosphere might be a lot though, and the wing might have to be not optimized for reducing it to make landing and low-speed flight easier? Are there air breathing hypersonic engine designs that can burn jet fuel or kerosene? Sagittarian Milky Way (talk) 20:27, 20 November 2018 (UTC)[reply]

Easy. Just pick a short enough distance where the suborbital only spends a second or two in space, and the 777X uses less fuel.
I haven't checked the numbers, but according to this[4] on many routes the fuel costs would be lower for suborbital.
If Musk pulls it off, we are talking 39 minutes New York to Shanghai, 22 minutes Hong Kong to Singapore, and 29 minutes London to New York. --Guy Macon (talk) 21:26, 20 November 2018 (UTC)[reply]
If you are interested in finding high quality reference material, at an introductory level that isn't too technical, I re-recommend "one of my favorite books". To Rise From Earth: An Easy-To-Understand Guide to Spaceflight shows the reader how to set up the basic problems in orbital mechanics. That book is written for a technically-inclined, but non-rocket-scientist, audience. (I last discussed this book in May 2017).
To directly answer the original question: No, there is no reasonable way for a suborbital point-to-point rocket transport to come anywhere close to the fuel efficiency of a jet aircraft. Exact values, quantities, and costs, are not particularly useful because all the details of sub-orbital passenger-transportation systems are still speculative fiction at this time; but most of the really hard theoretical obstacles aren't going to budge - not even with the advent of realistic near-future technologies.
Even the most enthusiastic scientific supporters - like the authors of this 2017 NASA Ames summary slide-deck on the future of commercial space - say that point-to-point sub-orbital travel is "not a current focus" and that it has ... "challenging technical problems."
If you really want to get informed, start by clearly defining "fuel efficiency"; by referring to the Boeing 777X article summaries about fuel burn; and reviewing the basics of the jet range equation (a topic covered in excruciating detail in another one of my favorite textbooks: Aerodynamics for Naval Aviators (Pages 150 through 180 in particular, with the jet section at Page 164)... and you can also read and understand specific impulse and review the propulsion comparison chart that manifests in just aboutevery other aerospace propulsion textbook ever written. Observe that even theoretically, a rocket is 30 or 50 times less efficient than any type of jet airline engine; and a rocket would have to be less efficient, because the rocket has to count fuel and oxidizer mass for its propellant mass.
This is literally a question about rocket science, and a lot of the difficult math might just confuse the point, so maybe the right thing to do is to summarize: "No."
No, there is no possible way that a sub-orbital space flight can be made anywhere close to the fuel-efficiency of a jet airliner. Even if you could solve all the other problems of a sub-orbital point-to-point transport rocket, using magic and pseudoscience, you'd still have to use even more magic and pseudo-science to make the fuel consumption anything that resembles the word "efficient."
Guy Macon: Let's refrain from linking to blogs that publish content under a fine-print disclaimer - "for entertainment purposes only" - those blogs are not encyclopedic references.
Nimur (talk) 22:32, 21 November 2018 (UTC)[reply]
Numbers are great, but to understand why a rocket will never be more efficient, just consider the physical principles. Typical heavier-than-air aircraft are powered by combusting fuel with oxygen in the air. This means they don't carry the oxidizer; it's basically "free". A chemical rocket has to carry oxidizer as well as fuel. And aircraft are held in the air by lift. Lift on a rocket is negligible; the thing holding it up is the thrust from the engines. This requires the engines to generate a lot of thrust continuously, and in a rocket, all of it must come from the exhaust generated by the propellant. In contrast, subsonic aircraft engines usually generate most of their thrust not from exhaust gases, but by pushing on the air. This is why turbofans are so efficient, as are propeller engines at lower speeds. Imagine if a turbofan aircraft had to carry all the air it pushed through the engines during a flight! --47.146.63.87 (talk) 07:24, 23 November 2018 (UTC)[reply]
Clarification: …subsonic aircraft engines usually generate most of their thrust not from exhaust gases…by "exhaust gases" I mean the products of combustion. --47.146.63.87 (talk) 09:20, 23 November 2018 (UTC)[reply]

When photons meet other photons

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Do they interfere? Does it matter whether they are travelling in the same direction, perpendicularly, or opposite directions? If there's no interference, does that mean that an infinite number of photons can be physically in the same place at the same time. Even if it's only for a tiny amount of time?--Doroletho (talk) 21:55, 20 November 2018 (UTC)[reply]

See Two-photon physics. Dmcq (talk) 00:08, 21 November 2018 (UTC)[reply]
See also Nonlinear optics; light can alter the medium through which it is travelling, and hence photons can indirectly interact with one another. Klbrain (talk) 01:11, 23 November 2018 (UTC)[reply]
Photons have wave-like properties, so yes, they can interfere, just as can waves in a body of water. As to the second question: yes, an infinite number of photons can occupy the same space. This is because photons are bosons, which obey Bose–Einstein statistics. In more formal terms, any number of photons can have identical quantum numbers. Fermions cannot; this is forbidden by the Pauli exclusion principle. This is partially responsible for the "solidness" of "ordinary" matter. --47.146.63.87 (talk) 07:34, 23 November 2018 (UTC)[reply]
It also should be noted that a photon (from its frame of reference) doesn't experience time, so speaking of being "be physically in the same place at the same time" is nonsensical; that's why we talk in terms of quantum numbers; since light doesn't experience time, it doesn't have a "place" at a "time" Light, from its own perspective, just exists everywhere along its worldline at all times. --Jayron32 17:27, 26 November 2018 (UTC)[reply]
And that's why we answer the question from a frame of reference where it makes sense (i.e., for a human observer), rather than describing a way to make the question nonsensical.... TenOfAllTrades(talk) 14:39, 27 November 2018 (UTC)[reply]