Wikipedia:Reference desk/Archives/Science/2014 February 26

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February 26[edit]

What star or planet did I see this morning near the Moon?[edit]

Looking at the Moon from Central Europe today, shortly before sunrise, there is a very bright star/planet in a near transit. There are no other stars visible in the sky. What is it? I'm guessing Venus because of its brightness, but looking at http://www.astroviewer.com/ I could not see anything large near the Moon. The closest is Mercury, but it is not as close on the map as I can see it (nearly touching the Moon) --188.26.23.191 (talk) 04:38, 26 February 2014 (UTC)[reply]

It's Venus. You can't see it on the current Astroviewer page because the word "Moon" happens to be on top of both the dot for Venus and the word "Venus". :-) --Amble (talk) 06:14, 26 February 2014 (UTC)[reply]
See this: http://apod.nasa.gov/apod/ap140227.html Bubba73 You talkin' to me? 05:29, 27 February 2014 (UTC)[reply]
If you have an android phone, you could point that towards the spot, and "Google Sky Map" would show you exactly which planet it was. Star Lord - 星王 (talk) 08:49, 27 February 2014 (UTC)[reply]

Electron diffraction lithography[edit]

Has anybody attempted to use Electron diffraction patterns with Electron-beam lithography to etch an entire chip all at once rather slowly cutting one line at a time in the chip? Hcobb (talk) 04:47, 26 February 2014 (UTC)[reply]

You may want to read Interference lithography#Electron holographic lithography and Electron holography. —Quondum 06:01, 26 February 2014 (UTC)[reply]
It has been attempted many times without success. You need to read about electron projection lithography or electron multi-beam lithography. Ruslik_Zero 19:20, 26 February 2014 (UTC)[reply]
Can you elaborate what you think happens. Mask creation and wafer fabrication are very different. So different that masks are created to resolve an edge with another mask to resole the other edge. Two masks for a single layer in the 16nm realm - lithography is often stepped and scanned (but not rastered like ebeam). There is nothing trivial in such fine details that need to be resolved. On the other hand, large structures such as pad or bump masks can expose an entire wafer at a single shot. Mask cost can vary from s few hunfred dollars to hundreds of thousand dollars depending on the feature size. --DHeyward (talk) 06:08, 27 February 2014 (UTC)[reply]

Relating Einstein Field Equation to Single Unified Field Theory[edit]

Is it correct to say that Einstein Field Equation is the Single Unified Field Theory? Are Einstein Field Equation and Single Unified Field Theory the same? 110.224.252.145 (talk) 08:23, 26 February 2014 (UTC)[reply]

Probably not. Solutions of the Einstein field equations highlights some limitations and boundaries. It's not a simple question. --DHeyward (talk) 08:58, 26 February 2014 (UTC)[reply]
According to this article Unified field theory, there is no accepted unified field theory. So the answer would clearly be no. Star Lord - 星王 (talk) 08:39, 27 February 2014 (UTC)[reply]

Organ on right hand side[edit]

chest cavity

Is there an organ just above the liver and below the right lung, or is it mostly muscle? KägeTorä - (影虎) (TALK) 22:40, 26 February 2014 (UTC)[reply]

I assume you're looking for Thoracic diaphragm. You might also be thinking that the heart is on the left side, but note that the lungs are very form-fitting structures; they're not simple sacs or mirror images. You briefly got me wondering how the diaphragmatic surface of liver keeps clear of ... mishaps, which leads me quickly to look up Chilaiditi syndrome.[1] It really is amazing, when I think of it, that a tender, flexible, blood-filled organ like the liver can sit so near to the repetitive stress of heavy breathing, yet (almost) never seem to trouble us about it. Wnt (talk) 22:57, 26 February 2014 (UTC)[reply]
If you're ever attacked by a Olympic silver medalist, kneeing them in that sweet spot seems to help. InedibleHulk (talk) 23:28, 26 February 2014 (UTC)[reply]
Personally, I attack my liver with alcohol. It's a lot less painful. --DHeyward (talk) 07:50, 27 February 2014 (UTC)[reply]

...says someone who has apparently never fallen backwards off a barstool, been dropped while doing a keg-stand, stepped on a broken beer bottle (or a pop-top, busted your flip-flop, and had to cruise on back home). DMacks (talk) 19:01, 28 February 2014 (UTC)[reply]