Sunday, June 16, 2013

Cosmography of the Local Universe

Above is an astounding video of the "Cosmography of the Local Universe," created by a team of scientists including astrophysicist and cosmologist Professor Helene Curtois, who narrates the video.

Pay close attention beginning at about 01:57 as the video takes you towards the tiny blue dot representing, not the earth, but the entire Milky Way galaxy during a "zoomed-in" view on our local region of the "local universe."  To paraphrase Professor Curtois, the enormity of what we are seeing is almost "overwhelming."

The effect is reminiscent of the famous 1977 video "Powers of Ten," which seeks to convey the scale of the universe by increasing (and then decreasing) the field of view by a power of ten every ten seconds (actually, every two seconds on the way back in).  That video, however, "only" takes the viewer out to a hundred million light years before streaking back in towards earth -- far enough to cause the Milky Way galaxy to shrink to a dot among its entourage of nearby galaxies, but still not much further than the "zoomed-in" 6-megaparsec cube from the segment just mentioned in the "Local Universe" video.   

A parsec is a unit of measurement whose name means "one parallax arc-second."  It measures 3.26 light years in distance.  A megaparsec is a million parsecs, or 3.26 million light years, equivalent to about 3.09 x 1022 meters. For more discussion of these distances, and the dimensions of the map in the "Local Universe" video, see this article from the LA Times.

These mind-numbing distances, and the scale of the universe they were created to help measure and define, invite profound existential reflection.  The wisdom of the ancients taught that every man and woman is a microcosm of the macrocosm of the universe, into whose vastness we stare every time we gaze into the starry heavens.  Videos such as this new "Cosmography of the Local Universe" help us to grope towards the meaning of such an assertion.

We should all be grateful to Professor Curtois and the team responsible (as well as to those responsible for the "Powers of Ten" video, produced thirty-six years ago).