To the Nth Power

September 30, 2008

The universe is really, really big. "Well, thank you, Captain Obvious," some of you might be thinking, but it's easy to under-appreciate the sheer vastness of space, even though this "fact" gets drilled into us early on in our education. And it just keeps getting bigger: not only is the universe still expanding, it's expanding faster and faster. How much we can see invariably has an impact on how much we understand. It's no accident that as our observational instruments have gotten better and better, we have been able to see farther and farther beyond our planet, and our knowledge and understanding of the broader universe we live in is thus that much more advanced.

Lots of attempts have been made to convey these literally astronomical size scales to the Average Joe (or Jane) -- not to mention how changing the scale can change our perception of the "true" picture of the universe by providing more and more context -- but by far the most successful was a 1977 short documentary film called Powers of 10. It is preserved in the US National Film Registry by the Library of Congress, which only selects films it deems "culturally, historically, or aesthetically significant."

Adapted from a 1957 book called Cosmic View (and suitably updated), Powers of 10 opens with an aerial image of a man on a blanket; we are told that this view is one meter across. The camera then zooms out to larger view (10 meters across), and we see that the man is actually picnicking in a park with a young woman. The camera continues to zoom out -- at the rate of one order of magnitude, or "power of 10," per 10 seconds -- and more and more information is revealed each time. We move from the young couple picnicking near Soldier Field in Chicago, all the way out to the furthest reaches of the (then) known universe.

But the film isn't content with merely wowing us with the jaw-dropping expanse of outer space. It then zooms back down to the starting point -- one meter -- and the man reclining on the blanket, then keeps going, giving us view after after view at an increasingly smaller size scale (negative powers of 10), right down to the point where we can "see" a carbon nucleus in the man's hand. The message is clear: our knowledge of the universe has expanded exponentially in both directions, from the very big down to the very small.

Small wonder Powers of 10 has inspired all kinds of museum and science exhibits to adopt a similar approach. In 1996, the Smithsonian Air and Space Museum released an updated IMAX version of the film called Cosmic Voyage, taking advantage not just of the breakthroughs in science in the ensuing years, but also in computer-generated special effects. The pivotal scene of two galaxies colliding purportedly took several days on the most powerful supercomputers to generate.

Powers of 10 really has become an integral part of our culture, including popular culture. The film Contact opens with a montage that mimics the documentary, taking the viewer from Earth to the edge of the universe before fading into the pupil of Jodie Foster's eye. More significantly, perhaps, is the fact this same visual gag has appeared in not one, not two, but three separate Simpsons episodes, each time settling back on a closeup of Homer's head.

And now XKCD's Randall Monroe has weighed in with his own contribution to the Powers of 10 meme, plotting the size scales vertically, rather than horizontally, with his usual whimsical touches:

Photo: XKCD/Randall Monroe.

Comments

[Winchell Chung]

Mr. Monroe builds upon the Princeton map work
http://www.astro.princeton.edu/~mjuric/universe/

Keeping in mind that Mr. Monroe has done some innovative original work disguised as a cartoon. For instance, cartoon
http://xkcd.com/195/
has been used by actual researchers
http://www.isi.edu/ant/address/

[Lab Lemming]

I love the cat.

[Nullsession]

Thanks for the article. I start off every semester's Astronomy 101 with Cosmic Voyage. The first two classes I always focus on looking at the universe from different perspectives (deep time, large and small scales).

Plus, cartoons always go over well. I'll have to link to XKCD on my astronomy site now.