Talk:Super-Jupiter

Definition Problems

This article is confusing to a layman, and needs the attention of an expert. Specifically, what is the definition of "largest cold mass"? Noclevername 10:26, 7 December 2006 (UTC)

A "cold body" is either a body that does not generate energy, or a body that does not generate energy by fusion. The first definition would exclude the Earth, since it generates energy by radioactive decay, so it is clear that the second definition is what is meant in this article. A planet and a white dwarf both fit this definition. The radius of a cold body is a bimodal function of its mass (composition and temperature being held equal), that is, as mass increases, radius increases, and then decreases. For example, the more massive a white dwarf is, the smaller its radius. The term "largest cold mass" denotes that mass at which the radius of a cold body is maximum. The value may depend on composition or temperature. Asimov and Dole, in Planets for Man, claimed that Jupiter has that maximum radius, more or less. But since then, it's been discovered that 51 Peg b, a transiting planet, has mass considerably less than Jupiter and radius considerably greater. This could be due to insolation, since 51 Peg b is very close to its star. If Asimov were right, any planet more massive than Jupiter would be a supergiant, by the definition given in the article. Vegasprof 11:25, 31 March 2007 (UTC)

Not only is this confusing, it's directly contradictory of itself. Rossheth 18:50, 7 December 2006 (UTC)

Original Research?

I do not believe that any authoritative source has defined the word ``supergiant planet``, although the term has been used in a few scholarly publications. (Unlike the term supergiant star which has an accepted definition.) Vegasprof 11:25, 31 March 2007 (UTC)

(I am copying here my remarks at talk:planetary mass type.) If there is any authoritative publication defining this term, it is not cited in this article. If it does not exist, this article should not be in Wikipedia. The term supergiant planet appears a few times, but very rarely, in the scientific literature, but always (as far as I can determine) in an informal way, i.e., without a definition. It would be very nice to have a classification scheme for planets, and I'm sure many will be seriously proposed, eventually. But at present, there are too few planets known. Before anyone came up with words like "giant star" and "supergiant star" and the like, many thousands of stars were known. When thousands of planets, their masses, radii, etc., are known, then it will be time to sensibly classify them. Vegasprof 22:03, 15 April 2007 (UTC)

PS: I am guilty of using the term supergiant planet on a fantasy website, which I believe is no longer up. There is at least one other fantasy website that uses the term. But, that is irrelevant to a serious encyclopedic article. Vegasprof 22:03, 15 April 2007 (UTC)