Hiya, it's been a while since I've posted here. I've been quite busy with school and graduate with my Associates in Computer Networking on May 30th and transfer to Southern Arkansas University to finish my Bachelors (Undecided, either AI or more networking stuff).

ANYWAY... during the winter break, I took up to reading "Planet Quest" by Ken Croswell.

Chapter 7 deals with the disagreement amongst astronomers as to what the definition of a star is, now that brown dwarves have been confirmed.

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(Loosely paraphrased from "Planet Quest".)

Shiv Kumar, who first published theoretical work exploring the existence of brown dwarves back in 1963, has run into considerable resistance regarding what genre of galactic bodies brown dwarves should fit into. Kumar's opinion is that brown dwarves fit into the category of stars because of their genesis: stars and brown dwarves are indentically formed by massive bodies of gas collapsing under it's own weight into a dense body. Some stars will have enough gravity to begin hydrogen-1 fusion (bodies with approximately >8 percent of the mass of the sun, by Kumar's work), and those become the main sequence stars, whereas some bodies will not have enough gravity to begin fusion, and these are doomed to never enter the main sequence, and spend millenia cooling and fading from sight.

Following the point that genisis should define what a given body is, when planets are formed, after accreting heavier rocks and ice into a body, the layers of gas are then attracted, as icing on a cake is put on last. Stars, on the other hand, form from the "top down", accreting all their gas from the onset and gaining little to no ice and rock. This, again, would place brown dwarves in the category of stars.

Another way to defend Kumar's point (that brown dwarves are stars) is that, for the past 100 years of so, stars have often been defined as objects that radiate their own light and non-stars (id est, planets) reflect their own light. By this definition, both white dwarves and brown dwarves fit in the category of stars. (At least until they have radiated most of their residual heat and no longer radiate in the white light spectrum.)

Opponents of Kumar's view say that the definition of a star is (paraphrased) "a body that radiates as much light from it's surface as it generates internally through fusion". By this definition, neither white dwarves nor brown dwarves fit, and must be considered entities of their own class.

Further, it can be argued that the definition of stars has changed in the past from "points of stationary light in the sky" to "self luminous bodies", and due to modern discoveries, it is time to redefine what a star is to "keep up with the times".

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Personally, I agree with Shiv Kumar on this point, but I can easily see how others might agree on the point that it is possible for a body to change enough properties to be considered a completly different class of entity (catapillar to a moth), or to have never reached a certain point in it's evolution to become a star (a heap of scrap that never gets fully assembled into a working automobile).

I was just wondering what other people on here might think about this.

Cheers!

MrPex