Brown Dwarf Stars May Be Missing Cosmic Link

An anonymous reader writes "It may be that brown dwarfs are the 'missing step' between the radio emissions we see generated by the planet Jupiter and what are received from pulsars. Brown dwarfs are, of course, 'failed' stars. They emit extremely strong beams of radiation, like a standard star, but are behaving on the whole more like a pulsar. 'Greg Hallinan from the National University of Ireland in Galway and his colleagues used the Very Large Array radio telescope in New Mexico to observe a very cool, rapidly rotating brown dwarf called TVLM 513-46546. A bright flash from the brown dwarf was observed roughly every two hours, and are very similar to those observed from pulsars. But this whole system is on a much slower and smaller scale, so it is easier for astronomers to decipher what is going on. For some time, scientists have wondered if there were similarities between this type of emission and the periodic radio beams from pulsars. Observations of TVLM 513-46546 could provide the first direct evidence for such a link."

Comments

"missing step"?

[khallow]

I'm unclear why there should be a "path" between Jupiter and neutron stars. By this, I mean there's no continuous range of density between the two. On the neutron star side, the jump from a star supported by electromagnetic repulsion to one supported by the strong force is a substantial jump in density and there's no intermediate step. On Jupiter's side, there's a profound change when going from no fusion (or to be honest, trivial amounts of fusion since fusion can in theory happen extremely rarely even at room temperature due to quantum mechanical tunnelling) to deutronium fusion and to regular fusion are big jumps as well.

Re:"missing step"?

[mikael]

I guess it's astronomical philosophy. Choose any two objects in the universe, and you should be able to find something inbetween. The more interesting objects occur at the critical point between two states (like the Schwarzschild radius for a black hole or the Chandrasekhar limit for supernovae). Objects just below these limits will often demonstrate numerous failed attempts to cross the threshold (A star might repeatedly attempt to go supernova by gaining mass from its companion, blow off some layers, only to fizzle out, then repeat the process months later). These observations give the chance to build more accurate models.