Tuesday, July 26 2011: My only friend, the end
"Such a low background temperature [the 2.7K background radiation left over from the Big Bang] does not directly affect us on Earth because our Sun (normally) grants us a cozy life. But as each generation of stars is born from clouds of interstellar gas, less and less gas remains to comprise the next generation of stars. This precious gas supply will eventually run out, as it already has in nearly half the galaxies in the universe. The small fraction of stars with the highest mass will collapse completely, never to be seen again. Some stars end their lives by blowing their guts across the galaxy in a supernova explosion. This returned gas can then be tapped for the next generation. but the majority of stars--Sun included--ultimately exhaust the fuel at their cores and, after the bulbous giant phase, collapse to form a compact orb of matter that radiates its feeble leftover heat to the frigid universe.
The short list of corpses may sound familiar: black holes, neutron stars (pulsars), and white dwarfs are each a dead end on the evolutionary tree of stars. But what they each have in common is an eternal lock on the material of cosmic construction. In other words, if stars burn out and no new ones are formed to replace them, then the universe will eventually contain no living stars.
How about Earth? We rely on the Sun for a daily infusion of energy to sustain life. If the Sun and the energy from all other stars were cut off from us then mechanical and chemical processes (life included) on and within Earth would 'wind down'. Eventually, the energy of all motion gets lost to friction and the system reaches a single uniform temperature. Earth, sitting beneath starless skies, will lie naked in the presence of the frozen background of the expanding universe. The temperature on Earth will drop, the way a freshly baked apple pie cools on a windowsill. Yet Earth is not alone in this fate. Trillions of years into the future, when all stars are gone, and every process in every nook and cranny of the expanding universe has wound down, all parts of the cosmos will cool to the same temperature as the ever-cooling background. At that time, space travel will no longer provide refuge because even Hell will have frozen over.
We may then declare that the universe has died--not with a bang, but with a whimper."
p 267, "Death by Black Hole" by Neil DeGrasse Tyson
The short list of corpses may sound familiar: black holes, neutron stars (pulsars), and white dwarfs are each a dead end on the evolutionary tree of stars. But what they each have in common is an eternal lock on the material of cosmic construction. In other words, if stars burn out and no new ones are formed to replace them, then the universe will eventually contain no living stars.
How about Earth? We rely on the Sun for a daily infusion of energy to sustain life. If the Sun and the energy from all other stars were cut off from us then mechanical and chemical processes (life included) on and within Earth would 'wind down'. Eventually, the energy of all motion gets lost to friction and the system reaches a single uniform temperature. Earth, sitting beneath starless skies, will lie naked in the presence of the frozen background of the expanding universe. The temperature on Earth will drop, the way a freshly baked apple pie cools on a windowsill. Yet Earth is not alone in this fate. Trillions of years into the future, when all stars are gone, and every process in every nook and cranny of the expanding universe has wound down, all parts of the cosmos will cool to the same temperature as the ever-cooling background. At that time, space travel will no longer provide refuge because even Hell will have frozen over.
We may then declare that the universe has died--not with a bang, but with a whimper."
p 267, "Death by Black Hole" by Neil DeGrasse Tyson
