Scale

[GordonCopestake]

Spotted this on another forum and thought people here would like to see it.

[FLO]

Wow :shock:

Great find Gordon - really puts things into perspective, literally!

[Astroman]

Excellent! :sunny:

[GordonCopestake]

Astroman, do you know how small an object can be before it attains fusion? ie where would a brown dwarf be on this "map"? Much larger than jupiter or only a little larger?

[GazOC]

I read somewhere that around 13-15 Jupiter masses is needed....

[GordonCopestake]

Wikipedia answered my question heh, I should have thought to look there first :

Brown dwarfs are sub-stellar objects with a mass below that necessary to maintain hydrogen-burning nuclear fusion reactions in their cores, as do stars on the main sequence, but have fully convective surfaces and interiors, with no chemical differentiation by depth. Brown dwarfs occupy the mass range between that of the lowest mass stars (anywhere between 75 and 90 Jupiter masses) and large gas-giant planets. Currently there is a large ambiguity as to what separates a brown dwarf from a giant planet at very low brown dwarf masses (~10 Jupiter masses). There is some question as to whether brown dwarfs are required to have experienced fusion at some point in their history; in any event, brown dwarfs heavier than 13 Jupiter masses (MJ) do fuse deuterium and above roughly 65 MJ fuse both deuterium and lithium.

[cappella]

i agree.. some people might say that giant planets like Jupiter are failed Stars, they have found that Jupiter has a very hot high pressure interior, who's to say that in the formation of the solar system, if Jupiter acquired more mass it would have become a Brown dwarf, or even a small star.. i have heard that there is some debate over some of the extra solar planets discovered, are these indeed planets or in some cases anyway, brown dwarfs. food for thought i think.. :Jupiter: