In space clouds of dust and gas are pulled together by the force of gravity. The particles all contact towards a central point. As it does so, gravitational potential energy is converted into thermal energy, heat, causing the core to heat up. 607 more words
Tags » Brown Dwarf
via HUMANOID HISTORY.
Concept art shows “what the weather might look like on cool star-like bodies known as brown dwarfs. These giant balls of gas start out life like stars, but lack the mass to sustain nuclear fusion at their cores, and instead, fade and cool with time.” (Spitzer/JPL)
Avid readers may remember a few years ago I blogged about the statistics of objects formed by disc fragmentation. In our paper, we looked at tidal downsizing, to see if big fluffy disc fragments with masses bigger than Jupiter could form solid cores and lose their gas to become objects of Neptune, maybe even Earth masses. 610 more words
It’s like something out of a Hollywood film or a science fiction novel: a dark star sneaks up on Earth from just outside the Solar System, discovered too late to do anything about it (and really, what could we do?) and plows through the cloud of comets that surrounds the Sun like a haze of icy gnats, sending them flying everywhere… including on collision courses with Earth. 551 more words