Talk:Solar System

"Heimdall"?

Surfing through the various language versions of "Solar System" and their discussions, I've found out that there is a certain uncertainty whether "Solar system" means anyone of them or just ours. My question: Has there been a discussion on this theme yet; and if not, would the term "Heimdall" for our "home world" be acceptable? Hellsepp 18:16, 1 May 2010 (UTC)

Heimdall is a crater on Callisto and Mars. Ruslik_Zero 18:18, 1 May 2010 (UTC)

Well, only our solar system contains the parent star Sol as the primary body. Thus only our solar system is a solar system.

Anything else is a planetary system.Carultch (talk) 09:57, 28 May 2010 (UTC)

Somewhat late: Thank you! Hellsepp —Preceding unsigned comment added by Hellsepp (talk • contribs) 23:24, 7 July 2010 (UTC)

Artist's rendering of the Oort Cloud, the Hills Cloud, and the Kuiper belt (inset)

Is this an oblique angle view or do they actually revolve in ovals? I think the distinction deserves mention. Richard LaBorde (talk) 23:04, 24 May 2010 (UTC)

Artist's rendering of solar system

What about that rendering? —Preceding unsigned comment added by 94.179.206.243 (talk) 16:26, 12 June 2010 (UTC)

Pending changes

This article is one of a small number (about 100) selected for the first week of the trial of the Wikipedia:Pending Changes system on the English language Wikipedia. All the articles listed at Wikipedia:Pending changes/Queue are being considered for level 1 pending changes protection.

The following request appears on that page:

However with only a few hours to go, comments have only been made on two of the pages.

Please update the Queue page as appropriate.

Note that I am not involved in this project any more than any other editor, just posting these notes since it is quite a big change, potentially.

Regards, Rich Farmbrough, 20:31, 15 June 2010 (UTC).

Inclination angle of the ecliptic

This page currently lists the ecliptic as being angled 86.5° out of the galactic plane. However, this is based on the source Swinburne Astronomy Online, which makes the rather shaky logical leap that the axial tilt of the ecliptic to the celestial equator must add fully with the tilt of the celestial equator to the galactic plane. This would only be the case if the axis of the Earth were precisely coplanar with a vertical radial plane of the galaxy, and moreover, if the center of the galaxy was to be found at approximately 18h and 86.5° inclination.

This statement of the tilt disagrees with the figure given in the Milky Way article of ~60° (second paragraph, 'Appearance from Earth' section). In addition, the Galactic Center article lists the position of the center of the galaxy as being at RA 17h45m40.04s, Dec -29° 00' 28.1". I've been unable to find independent verification of either of those values, and neither is cited, but both are consistent with one another, as shown in this rough model I threw together in Mathematica: [1]

The angle indicated by this model is roughly 60° ([2]), though the manner in which I modeled it does not allow precise measurement. This is my first post on Wikipedia (in fact, I registered just to post this), so I'm unsure as to the standard practice in these cases. I know citation or at least independent verification is likely needed for the location and axial tilt given, though, so I figured I'd post this here where more experienced wikipeople can handle it. --Michael Leuthaeuser 07:44, 1 August 2010 (UTC)

Ideally, a source is required that is scientifically accurate and drawn from some kind of recognised authority. Unfortunately, any work you do, unless you publish it on a university site or other such credible source, would be considered original research by Wikipedia standards. I'm not particularly fond of the source I used for that info, so if you can locate a better one, I'd very much appreciate it. Serendi^podous 07:57, 1 August 2010 (UTC)

My calculations also show that it is close to 60°. If ψ is the angle between the north pole of the ecliptic and the north galactic pole than:

$\cos \psi =\cos(\beta _{g})\cos(\beta _{e})\cos(\alpha _{g}-\alpha _{e})+\sin(\beta _{g})\sin(\beta _{e})$,

where $\beta _{g}=$27° 07′ 42.01 and $\alpha _{g}=$12h 51m 26.282 are the declination and right ascension of the north galactic pole, while $\beta _{e}=$66° 33′ 38.6″ and $\alpha _{e}=$18h 0m 00 are for the north pole of the ecliptic. Ruslik_Zero 09:02, 1 August 2010 (UTC)

So can we use it? Or do we need a citation to back up, not the calculations themselves, but the basis behind them? Serendi^podous 13:28, 1 August 2010 (UTC)

[3] I'm not incredibly at interpreting this programming script, but it seems to confirm that math, and it's from a .gov (NASA, at that). --Michael Leuthaeuser 17:22, 1 August 2010 (UTC)

[4]Yet another source, this time published textbook, showing the same math. Neither list the angle explicitly, though.--Michael Leuthaeuser 17:43, 1 August 2010 (UTC)

That's fine; if we have the math we can add it in a note and use these sources to back up the facts. We may also need a source to verify the math. Serendi^podous 17:48, 1 August 2010 (UTC)

I corrected the value in the article. Ruslik_Zero 13:10, 8 August 2010 (UTC)

Depiction of planets inadequate

It seems poor that, on the Mother of All Online Encyclopedias Anyone Can Edit, such a poor visual rendering of the planets is given. It is inadequate, for example, to convince one that the 'Dwarf Planets' are indeed dwarfish (an impolite way, incidentally, of saying notably small). What does come out from the picture is, in fact, that two of the planets are noticeably gigantic, and I refer here not to the 'gas giants,' which give rise to a further problem: having grasped the idea that the 'gas giants' are deceptively large, being composed mainly of gas, it seems necessary to present the viewer with a clear visual impression of the discrepancy between the planets' volume and that of their solid cores - this the diagrams fail to do. —Preceding unsigned comment added by 79.78.35.71 (talk) 18:43, 1 September 2010 (UTC)