[X] My Assistant

[Guest_Myran_*]

NASA sponsored astronomer Michael Brown of CIT just announced he have found a 10'th planet.
The claim was made for one object based on its brightness alone and that for one object at 3 times the distance of Pluto. In short its smack in the middle of the belt of other KBO's.
The guy claim he was forced to reveal his data since a hacker had threatened to release information about the object.
Im strongly unconvinced about that story.
Why then claim it to be a planet rightoff. More likely think this guy must be looking for the fame of Clyde Tombaugh.
Without any infrared measurements or to establish the albedo properly which would have given a guesstimate of the objects size he singlehandedly claim a KBO planet, this should get the Bad astronomy 1'st price prize for preposterous extrapolation from a single unconvincing piece of scientific data.

[edstrick]

".... I'd expect these brown dwarf systems to greatly outnumber all the visible stars....."

The IMF (Initial Mass Function) or size distribution of new stars shows a rather sharp rolloff in the frequency of very low mass M stars and that appears to continue and get stronger into brown dwarfs. It's very hard to measure the IMF of mature stars in the solar vicinity as the faintest are so faint that catalogs become very incomplete at distances of very few light years.

However, It's much easier to study mass/abundance distributions of stars in young clusters, where low mass M stars and brown dwarfs and even rogue-planets still have very substantial thermal output from formation. In addition, they're studying faint object abundances all the way from star-forming regions like Orion, to young clusters like the Pleiades to older clusters like the Hyades.

There is also a *LOT* of theoretical work on variations in the IMF between different types of star forming regions, low-mass-leisurly-accreting nebula to super-star-forming-complexes with high supernova rates and lots of super-heavy stars.

I'm barely familiar with the literature, but it's out there. The main point is that low mass M and brown dwarf stars are much less abundant than simple extrapolation of brighter star abundances used to suggest.