# User talk:Eltwarg

Welcome!

Hello, Eltwarg, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are a few good links for newcomers:

I hope you enjoy editing here and being a Wikipedian! Please sign your name on talk pages using four tildes (~~~~); this will automatically produce your name and the date. If you need help, check out Wikipedia:Where to ask a question, ask me on my talk page, or place {{helpme}} on your talk page and someone will show up shortly to answer your questions. Again, welcome!

## TeXnical issues

Hello. Please note that curly braces around the subscript are needed for things like this:

${\displaystyle \aleph _{i+1}.\,}$

Click on "edit this page" and you will see how that was done. Similarly, in

${\displaystyle x^{43},\,}$

without the curly braces around the numeral "43", only the "4" appears in the superscript; the "3" does not. Same thing with

${\displaystyle {\sqrt {43+65}},\,}$

etc. Michael Hardy 00:32, 30 July 2005 (UTC)

## Fun

In general, it seems like it is going to be a playground of non-human perfectionists (especially in the math section ;-). Probably I should take it all much more seriously - the problem could be I am too "fun-oriented" (with little son you must be ;).

Hello. I think no one's more "fun-oriented" than I am, but I don't see that as conflicting with seriousness; for me, they're largely the same thing. The more playful it is, the more serious it is, and vice versa. Michael Hardy 01:15, 15 August 2005 (UTC)

Finally I want to say that I think I understand people who do not like your enhancements in "their" articles. I do not like too much "academical" approach to Wikipedia too and do prefer more human aspects if do not interfere with the purpose. One of the basic human aspects is "not to be perfect" what as I believe do not interfere much with purpose of Wikipedia in general.

I don't understand the point above at all, since it is completely non-specific. Could you please give some examples? Sometimes I don't like people's edits to article's I've started, but I know they're not "my" articles. Do you mean that correcting spelling or punctuation is not "human" enough? Or changing an erroneous assertion to a correct one is not "human" enough? The purpose of Wikipedia is to make information available. If you can point out some edit of mine that was does not support that purpose, please do. Certainly you can find some errors among my many edits, but I doubt that's what you're trying to say. Also, no one has expressed to me that they regard any article as "theirs" and dislike my edits for that reason. Has someone indicated that to you? If so, I wonder why they don't say that to me. Michael Hardy 01:03, 15 August 2005 (UTC)

## Alpha Centauri orbital plot - spatially ambiguous

Hi Eltwarg, I am wondering whether you might include spatial information into the apparent orbit of Alpha Centauri A+B. I had been searching the web for ages for such an information, but it seems to be nowhere given. The File:AlphaCentauri AB Trajectory.gif is ambiguous here since it no spatial information is given here (in particular, which part of the orbit is closer to the observer, and which one is more distant?). I neen this information since I want to create a model how both stars are orientate with respect to the Solar System. But currently there are exactly two ways, not one, how to interpret the orbit. In fact, the plot does not show the trajectory, but a 2D projection of it. The trajectory would require all the information. Many thanks in advance!--SiriusB (talk) 23:19, 27 June 2010 (UTC)

Update: According to Pourbaix et al. (2002, the reference for orbital elements in the Article Alpha Centauri, see [1]) the relative radial velocity of A vs. B became zero (i.e. both had the same RV wrt. the Sun) in 1927 (interpolation of the time marks in subfigure of Fig. 2), and so in 2007 one orbital period later. B's RV curve is that with the larger amplitude (open symbols) due to its lower mass, and it switched from larger to smaller than A's RV in 2007, so it reached its maximum radial separation from A behing behind A. In other words, α Cen A is currently the second nearest neighbour to the Sun after Proxima. Maybe one could create another orbital plot with the following improvements: 1. Color (or other) coding of the near/far position of B vs. A, 2. timestep set to 1 year (or, as a good approximation, 1/80 of the orbital period), 3. labels for periapsis and apoapsis position with years (next periapsis will be in May/June 2035). I would do it myself, but however, do not have the appropriate tools to create these nice shiny sun-like points in the figure. Note that the times refer to the arrival of the light at the Earth. The true times are 4.365 years ealier (neglecting any special or general relativistic corrections). As a first step, I have mentioned the far position of B in 2007 in the (now rather full) caption.--SiriusB (talk) 09:35, 29 June 2010 (UTC)

Update #2Your new version looks good, and your assumption of B being nearer than A at periapsis is correct. I cannot say whether the apparent angular distance is maximal at 2056 or 2060 without another calculation. Hmm, I didn't put in that information in the text, did I? Maybe the difference is due to taking the real-time orbit rather than the apparent orbit some 4.4 years delayed due to the light travel time. The data in my (and your) plot should represent the apparent orbit as seen from the Earth.--SiriusB (talk) 08:46, 1 December 2011 (UTC)

P.S.: Did you also consider uploading the image on Wikimedia Commons?--SiriusB (talk) 08:52, 1 December 2011 (UTC)