Time

I have a hard time with time.  I suspect this is because my brain is structured to understand time in a way that is relevant to survival.  A minute, an hour, a day, a year, a decade, a lifetime - these are all comprehensible.  But all that - all the time I will experience in this life, is less than a blink of an eye on the cosmic scale.

Two articles I read recently speak to those longer, deeper times - that we can somehow grasp at least as numbers - but which stretch orders of magnitude beyond our direct experience - not only as individuals, but as a species.

One was an article in the January 2014 Smithsonian magazine about the Messel Pit in Germany, a site dating back some 48 million years.  A former mine, it has yielded the most fossils from the Eocene period, the period when mammals spread throughout the ecosystem, evolving rapidly to replace niches left vacant by the extinction of the dinosaurs.  48 million years.  That's about 600,000 lifetimes, and about 240 times as long as modern humans have existed, based on fossil and genetic evidence placing our emergence at about 200,000 years ago.  It's also about half of the estimated 100 million years or so that a comet, asteroid, or other object large enough to cause a mass extinction collides with the earth.

The second was about new conclusions about a "collision" between our Milky Way galaxy and the Andromeda galaxy - which is currently a pretty comfortable 2.5 million light years away, but moving slowly in our direction.  Current information indicates that the two galaxies will merge in about 4 billion years from now.  Coincidentally, that's about the time in our own Sun's lifespan that increasing radiation will have killed most life on earth's surface.  4 billion years.  That's 50 million human lifetimes, and 20,000 times as long as humans have existed.

So, what's the likelihood that humans, with our sense that we are the most important things in the universe, will be around, in a million or a billion years?  My guess is zero.  The pace of biological evolution alone makes it seem likely that we won't be the same organisms in a few hundred thousand years at best - if we don't suffer from any of the major calamities that have caused previous species to go extinct on this planet.

In one sense, it's amazing that our brain, which needs to track time so it can understand the flight of an arrow, or how far one could travel before dark, or when was the season to plant, can even formulate the concept of a million or a billion years.  But we seem to have a hard time grasping the truth about what this means for our place in the universe.  We're one life form that will exist for a tiny slice of cosmic time on one planet out of billions.

So, even though I can't really comprehend these huge stretches of time that are behind us and before us, I can grasp enough to realize that the meaning of my life has to be found somewhere other than thinking I am the Master of Universe.