You may not know it, but we're reasonably sure how it all ends. I'm not talking about The Avengers, whether the White Stripes are going to get back together, or the inevitable bloody conclusion to The Song of Ice and Fire books, I'm talking about everything. As far as we can tell, nothing will escape the heat death of the universe. Even if we, as a species, manage to escape the gravity well of our solar system and outlast the eventual demise of the sun, our fate is sealed.
The good news is that we have a while.
When you're talking about astrophysics, it's important to maintain your sense of perspective. On Monday afternoon, your plans for the upcoming weekend might seem eternally distant, but in reality, Saturday afternoon is only about 441 kiloseconds away. It's difficult to maintain perspective on a work week, much less the geological scales we all learned in grade school. But when you're talking about astrophysics and the potential heat death of the universe, the time scales you're working with redefine mindboggling. Here's something to help your sense of perspective.
I'm just going to point you to a few highlights from Wikipedia's Timeline of the far future. It doesn't include anything about Zephram Cochrane or the discovery of the first Stargate [Norm's note: that was in 1928], this is all real stuff that should happen in the future, assuming our current understanding of geology and astrophysics is correct, of course.
First stop on the tour of the future is Pioneer 10's closest approach to Barnard's Star, in 10,000 years. A mere 26,000 years after that Ross 248 passes within 3.024 light years of the Sun, temporarily taking the title of "closest star" from Alpha Centauri. In 50 million years, California coastal real estate will dramatically decrease in value as it's subducted into the Aleutian Trench. Don't worry though, about 250 million years in the future, plate tectonics will push the remaining landmasses into one supercontinent or another Pangaea or maybe another Amasia.
Fast forward a bit to 800 million years from today, when carbon dioxide levels in the atmosphere will have fallen so far that photosynthesis is no longer possible, dooming all plant life in the process.
At this point, things get a bit dicey if you're still on the Earth. I'll fast forward a bit, but know that pretty much the nicest thing that happens to Earth over the next three billion years is that there's a small chance that Mercury will smash into Venus and knock Earth away before the sun goes red giant in about 7.9 billion years.
Of course, compared to the heat death of the universe, 7.9 billion years is peanuts. In about 100 trillion years, all new star formation in all galaxies will cease. Another 10 or 20 trillion years after that, all stars will have exhausted their fuel.
Most likely, the whole thing will be over 10^(10^26) years from now. By that time all matter could have collapsed into black holes, depending on which group of particle physicists ends up being right. Not that we'll really care, 10^(10^26) years is fascinating number on its own, and responsible for my new favorite footnote on Wikipedia:
10^(10^26) is 1 followed by 10^26 (100 septillion) zeroes. Although listed in years for convenience, the numbers beyond this point are so vast that they would be the same in whichever conventional units one could conceivably list them in, be they nanoseconds or star lifespans.
You read that right: 10^(10^26) years is such a stupendously huge amount of time that the difference between a nanosecond and the lifespan of a star becomes a rounding error.
Saturday afternoon doesn't see so far away now, does it?
Thanks to Twitter user Jonty Wareing for sending me down this rabbit hole this morning.