Talk:List of solar system objects by mass
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I started this page with the expectation that it would be relatively easy to find masses for the planets and their moons, and a few of the major asteroids and planetoids and so forth. The masses of the planets are fairly well known, but I had a ridiculously difficult time trying to find good, reliable sources for the masses of moons (especially those of Uranus and Neptune). I tried NASA's Solar System Exploration (http://solarsystem.nasa.gov/planets/) page, which appears to give pretty good values for most moons. As I started updating the masses to match those given by SSE, however, I noticed that the masses of many moons (31, in fact) are given as 8×1017 kg. It appears that SSE is using this number to indicate an uncertain or unknown mass rather than simply saying "unknown," which makes me question the accuracy of the other numbers. Until I can resolve that, I'm going to avoid using SSE values, so if anyone knows of other reliable sources, please post them here or update the page yourself. --Bkell 22:42, 19 Mar 2004 (UTC)
- I think those moons are listed at that number because they're all rounded to around the same size. Most of the newly discovered moons have very little known about them. I've seen orbit sizes changed by more than ten million kilometers in months. At this time, we only have very rough estimated of thir size, and the masses are probably inferred from estimating the mass of a sphere of that size with a guessed density. Anyway, I admire the effort put into this page, I've always wanted to try something like this myself, but I'd never been able to find enough reliable info on objects under the size of Ceres. --Patteroast 00:00, 6 Apr 2004 (UTC)
I originally started this page as a table, and then moved to an ordered list, since it seemed to me that it would be nice to be able to quickly ascertain a given object's rank in the solar system. Curps changed it back to a table today, which has its benefits, among them the fact that the masses are nicely aligned. The problem is that now the ranks are gone.
I realize that assigning rankings to some of the objects lower in the list is somewhat misleading, since it's very likely that there are larger objects in the solar system that just aren't in the list because their masses aren't well known. But I think it would be nice to have rankings for at least the first few objects; after all, I think we're fairly certain that Earth is the sixth most massive object in the solar system, so it would be nice for it to be labeled "6".
Perhaps we can just add another column down the left side of the table for the rank. Any opinions out there? —Bkell 03:50, 14 Apr 2004 (UTC)