Superman's powers come from being near a yellow sun as opposed to the red sun of krypton. Occasionally Superman will travel to other planets/off-world to help some other cause or force.  I'm curious, has any writer had the man of steel utilize the radiation from another different colored (blue, white etc) sun for his powers? Do hotter stars have similar affects, or are Kryptonian powers only activated by yellow suns?
With the Superman lore, we know that light from a yellow star gives him his powers, light from blue stars makes him stronger, and light from red stars weakens him.  However, what happens if he is near a white dwarf, or a neutron star?  Has there been any evidence of Superman visiting a star system that wasn't red/yellow/blue?
Make clear in the logon screen you can log in with your SE account don't really understand how to log on with your SE account in the new logon screen.  And although it might be obvious to most of us, some people find the new dialog hard to understand.        Can we add a logo and some text to make clear users can log on with their SE account? Something like:     [SE LOGO] Log on using your StackExchange account   Followed by the two boxes for email and password. I'll like to add this functionality to the autocomplete widget in Entityreference field to show node ID next to the titles in the dropdown list. The reason behind the idea is to differentiate between multiple nodes with same title.  Example:    This is a title (3) This is a title (2) This is a title (1)   I know the node ID is shown once a selection is made but I like to show it in the dropdown list in order to pick the right node quickly based on the node ID. How to reset the Xorg / xserver? Xserver keeps crashing on my general user account both in Unity 3D and 2D. It doesn't do it on the guest account.  That's why I want to reset / rollback everything xserver related, hoping this is going to fix it.  Most answers on this involve sudo dpkg-reconfigure xserver-xorg. However, this does nothing for me (generates no output) and I read in other forums, that it's deprecated.  So, what's the current way to reset all xserver / xorg options; what's the alternative to sudo dpkg-reconfigure xserver-xorg? X crashes during work, not before login or so. And the effect of a crash is, that I get thrown out of the session, not a freeze or machine crash. Does $\sum_{k=1}^{\infty}\ln(\frac{k}{k+1})$ converge/diverges?? Does this series converge or diverge? $$\sum_{k=1}^{\infty}\ln(\frac{k}{k+1})$$   my thought is that, I can break it down to $$\sum_{k=1}^{\infty}\ln(k) - \sum_{k=1}^{\infty}\ln(k+1)$$ then maybe using comparison test or something? But I don't know exactly how to prove whether this series converges or diverges.  Any help would be appreciated! ravel: opposite meanings? Use a vector as an index to a matrix How do I go about porting Ubuntu Touch to different devices? What is the difference between CurrentCulture and CurrentUICulture properties of CultureInfo in .NET? In .NET there is the CultureInfo class in the System.Globalization namespace. It has two similar properties both returning values of the CultureInfo type: CurrentCulture and CurrentUICulture.  What is the difference between them?   Which one should I use when and why? SBS 2011 - Is Store.exe High Memory Usage Normal? How to fit a tight ellipse around nodes I have a set of two nodes and I would like to draw tight ellipses around them in my tikz picture. Note that this is part of a beamer presentation.    I have attached an image that illustrates the wanted effect.    Here is what I have so far:  \documentclass[10pt,aspectratio=1610]{beamer} \usepackage{tikz} \usetikzlibrary{shapes,arrows,backgrounds,fit,positioning}  \begin{document}  \tikzset{res/.style={ellipse,draw,minimum height=0.5cm,minimum width=0.8cm}} \tikzset{literal/.style={rectangle,draw,minimum height=0.5cm,minimum width=0.8cm,text width = 1.2 cm, align = center}}  \begin{frame}[fragile]{Example}{} \begin{tikzpicture}[node distance = 2 cm,auto, ] \node[res,] (obs1) {\footnotesize :obs1} ; \node[res, left = 1cm of obs1] (shop1) {\footnotesize :shop1} ; \node[literal, left = 1cm of shop1] (shopName1) {\footnotesize ``Barnes \&amp; Noble''} ; \node[res, above of = shop1] (book1) {\footnotesize :book1} ; \node[literal, left = 1cm of book1] (bookName1) {\footnotesize ``Dune''} ; \node[res, below of = obs1] (obs2) {\footnotesize :obs2} ; \node[res, left = 1cm of obs2] (shop2) {\footnotesize :shop2} ; \node[literal, left = 1cm of shop2] (shopName2) {\footnotesize ``Amazon''} ; \node[res, below of = shop2] (book2) {\footnotesize :book2} ; \node[literal, left = 1cm of book2] (bookName2) {\footnotesize ``Dracula''} ; \node[literal, below of = obs2] (measure2) {\footnotesize 12} ; \node[literal, above of = obs1] (measure1) {\footnotesize 7} ; \node[literal, right = 1cm of obs1] (monthName) {\footnotesize ``January''} ; \node[literal, right = 1cm of measure1] (yearNum) {\footnotesize ``2016''} ; \node[res, right = 1cm of monthName] (month) {\footnotesize :january2016} ; \node[res, above of = month] (year) {\footnotesize :2016} ; \node[res, below of = month] (day) {\footnotesize :date31012016} ;  \path[-&gt;,draw]     (obs1) edge node[midway,above=-6pt,fill=white,inner sep=0pt] {\footnotesize :shop} (shop1)     (obs2) edge node[midway,above=-6pt,fill=white,inner sep=0pt] {\footnotesize :shop} (shop2)      (obs1) edge node[midway,above=-6pt,fill=white] {\footnotesize :book} (book1)     (obs2) edge node[midway,above=-6pt,fill=white] {\footnotesize :book} (book2)      (book1) edge node[midway,above=-6pt,fill=white,inner sep=0pt] {\footnotesize :name} (bookName1)     (book2) edge node[midway,above=-6pt,fill=white,inner sep=0pt] {\footnotesize :name} (bookName2)      (shop1) edge node[midway,above=-6pt,fill=white] (title1) {\footnotesize :title} (shopName1)     (shop2) edge node[midway,above=-6pt,fill=white] (title2) {\footnotesize :title} (shopName2)      (obs1) edge node[midway,above=-6pt,fill=white] {\footnotesize :price} (measure1)     (obs2) edge node[midway,above=-6pt,fill=white] {\footnotesize :price} (measure2)      (obs1) edge node[midway,above=-6pt,fill=white]  {\footnotesize :date} (day)     (obs2) edge node[midway,above=-6pt,fill=white] {\footnotesize :date} (day)      (day) edge node[midway,above=-6pt,fill=white] {\footnotesize skos:broader} (month)     (month) edge node[midway,above=-6pt,fill=white] {\footnotesize skos:broader} (year)      (month) edge node[midway,above=-6pt,fill=white,inner sep=0pt] {\footnotesize :month} (monthName)     (year) edge node[midway,above=-6pt,fill=white] {\footnotesize :year} (yearNum)     ;  \begin{pgfonlayer}{background}   \node[fit=(shopName1)(shop1), fill=violet!30,ellipse] {};   \node[fit=(shopName2)(shop2), fill=violet!30,ellipse] {};   \node[fit=(bookName2)(book2), fill=violet!30,ellipse] {};   \node[fit=(bookName1)(book1), fill=violet!30,ellipse] {};   \node[fit=(measure1)(obs1), fill=blue!30,ellipse] {};   \node[fit=(measure2)(obs2), fill=blue!30,ellipse] {};   \node[fit=(year)(yearNum), fill=green!30,ellipse] {};   \node[fit=(month)(monthName), fill=green!30,ellipse] {}; \end{pgfonlayer} \end{tikzpicture} \end{frame} \end{document}   Here is the result that it produce    Note how the ellipses do not fit the nodes but cover much more. How can I create a tight ellipse around a pair of nodes? Simple way of finding the locus of $z$? I am tasked to sketch the locus of complex numbers $z$ that satisfies $$(z-2+i)^2 + (z^*-2-i)^2 + 2zz^* + 6 = 0$$ I was wondering if there’s a special trick to this question, or if this is only solvable by plugging in $z=x+iy$ ? I noticed that the second term is the conjugate of the first, and wanted to substitute $w = z-2+i$, however this gives me a complicated expression for $zz^*$ which makes it more confusing. Is there a trick I’m missing out? Thanks! Edit: I have already solved it through direct substitution (parabola intersecting real axis at $x=3$ and $x=-1$) but it took a good 5 minutes or so, expanding everything correctly, which seems rather long (I was attempting it under exam conditions). I was just wondering if it is possible to exploit the $w$ substitution I made in particular. Number of equivalence relations on a set If a set has $n$ elements then what are maximum number of equivalence classes and equivalence relations possible on it? C# Settings.Default.Save() not saving? How to setup two completely separate partitions on one SSD I have a MacBook with 1TB SSD. I want to have two separate partitions with two independent macOS installations. I want to make sure that none of the partitions have any kind of possibility to interact with the other, I want them to be as separated as if they were physically separate. Is this achievable with, for example, FileVault for each of them? Edit: My question is neither &quot;how can I install two different macOS versions on two different partitions on one SDD&quot;, neither &quot;how do I use FileVault&quot;, etc. I know how to do all of that. I want to make sure that there is no interaction between the partitions possible. Can this be made sure with the above approach? Is it sufficient? How should I structure my URLs for both SEO and localization? How old is too old for a PhD? Are there any age limits (formal, informal, or guidelines) that schools use when deciding to accept someone into a PhD program? I'm most curious about the upper age limits. For example, will most schools accept someone in their 40's? How about their 50's? arbitrary large finite sums of an uncountable set. Fusion: Why deuterium and tritium? I would like to know why scientists try to use deuterium and tritium for  and not just the ordinary  ${}^1H$? I'm trying to write a simple bash function that takes, as its arguments, a number of files and/or directories. It should:   Fully qualify the filenames. Sort them. Remove duplicates. Print all that actually exist. Return the number of non-existent files.   I have a script that almost does what I want, but falls down on the sorting. The return value of the script as it stands is correct, but the output is not (unsorted and duplicates). If I uncomment the | sort -u statement as indicated, the output is correct but the return value is always 0.  N.B. Simpler solutions to solve the problem are welcome but the question is really about why is this occurring in the code I have. That is, why does adding the pipe seemingly stop the script incrementing the variable r?  Here's the script:  function uniqfile {     local r=0       for arg in "$@"     do           readlink -e "$arg" || (( ++r ))      done #| sort -u    ## remove that comment      return $r } What happens with the force of gravity when the distance between two objects is 0? so I had my first approximation to the gravity equation  \begin{equation} F=GmM/r^2 \end{equation} and some questions arose that my teacher couldnt respond: if r approximates to 0 with mM being constant, then the force should tend to infinity, right? so that being true, then if we would travel to the center of the earth, we would be crushed by gravity? if so, how can there be anything right in the center of the earth? wouldnt anything there be compressed and destroyed by the infinite force?  having that in mind, my next question is as gravity force is measured from the center of an object, any part of the same object which is not at the center would be affected by the same object's gravity? if so, how can we differentiate between two objects that are not in a vacuum? my question originated thinking in us standing on the earth, in contact with it, are we, in a gravitational sense, one object? this lead to the last question, if gravity is a property of matter, then how applying the same logic as before, how does it work between two neutrons?(chose neutrons because i assumed it would be more difficult obtaining gravitational force if there was electrostatic forces from charges inbetween) do two newtrons in contact count as 1 gravitational object? and how thats its own gravity affect the newtron from center and out?