Support Provided ByLearn More

The Very Big And The Very Small

The Secret Life of Scientists and EngineersThe Secret Life of Scientists and Engineers

Receive emails about upcoming NOVA programs and related content, as well as featured reporting about current events through a science lens.

Click here for Stephon’s profile.

Stephon studies the connections between things that are enormous—like universes—and things that are teeny—like neutrinos. I already know of one shared feature: their size is incredibly difficult for me to wrap my mind around.

Support Provided ByLearn More

The observable universe is apparently 92 billion light years across. But how big is that, really? In my head, that means about the same as if it were 92 million, or 92,000, or 9.2 light years across.

A neutrino—which is a particle, like an electron, except with neutral charge—has mass, but the number is debated : it’s somewhere between 0.05 to 0.58 electron volts. Huh? What’s an electron volt?

The Very Big And The Very Small-universe_for_blog.jpg
It all looks teeny here… but it’s enormous.

I’m not the only one who struggles with conceptualizing the very big and the very small. Luckily, my neighborhood science museum—the American Museum of Natural History , in Manhattan—has a fabulous exhibit to help us out. It’s called the “ Scales of the Universe .”

The exhibit spirals around an 87-foot planetarium, called the Hayden Sphere, which becomes a reference point for all of the objects around it. For instance, you might stand in front of a 10-inch globe with the big dome behind it. The exhibit text tells you that if the dome were the sun, then the globe would be the earth. If the dome were a raindrop, the globe would be a red blood cell. If the dome were a red blood cell, the globe would be a rhinovirus. And if the dome were a rhinovirus, then the globe would be a hydrogen atom.

Pretty cool way to think about size, right? Plus, if you walk up the spiral path that leads to the planetarium, you’ll see a timeline of the earth’s history, beginning with the Big Bang and ending with present day. On this scale, the era of human existence spans the width of a human hair.

So next time you’re in the Big Apple, make sure to stop by. It’ll blow your mind.

Photo by ajstarks on Flickr

Original funding for "The Secret Life of Scientists and Engineers" was provided by the Alfred P. Sloan Foundation.