Radio Workshop

Dark Energy (Transcript)

by Piya Kochhar

NARRATION:

On most nights, astronomy students Mark Dijkstra and David Spiegal look to the sky for their answers. They can identify most of the stars in our galaxy.

ACT/AMB:

Hear telescope going up... "That's Jupiter, it's quite high up."

NARR:

But the universe beyond our galaxy remains a mystery to these two. Which is why a few weeks ago their gazes were fixed on a TV screen rather than on the sky. A discovery by NASA scientists not only pinpointed the age of our universe to 13.7 billion years old, but also confirmed what it is made up of. Scientists say,we know and understand only 4 percent of our entire universe. The other 23-percent consists of vague dark substances. And another 73-percent is comprised of a mysterious force called "Dark energy." For David Spiegel this discovery is a humbling experience.

DAVID SPIEGEL:

I think the idea that 73 percent of the universe is made up of something we have absolutely no idea what it is, and another 23 percent is made up of something we don't have much better idea what it is, and only 4 percent of the universe is made up of anything that we have any idea about at all... it's a little bit of a lesson for human humility that we really don't know what's going on out there.

NARR:

Dark Energy was listed as the biggest mystery of our time by Space.com, a science webzine. Robert Britt is a senior science writer there.

BRITT:

The fact that astronomers came up with this name dark energy...it really lends a mysterious air to the concept...and perhaps that's appropriate...because it is mysterious. The only thing they know about it, is that it's there and that it works.

NARR:

Britt says Dark Energy is causing our universe to grow bigger and bigger, faster and faster. It works opposite gravity. While gravity works on a local level to hold our solar system together, Britt says Dark Energy works on a large-scale universal level to pull things apart. Scientists used to think the universe might one day stop growing and perhaps contract in what they call a Big Crunch, but Britt says this theory seems unlikely now.

BRITT:

Gravity is in a sense failing. It's succeeding at a local level but on a universal level, gravity has lost the war to dark energy.

NARR:

As a result, our universe is constantly expanding at a faster rate. And, according to this theory, the expansion will go on forever and ever. But... So what? What exactly does the discovery of an ever expanding universe mean to us here and now? Will life as we know it alter course? Unlikely, says David Helfand, chair of the Astronomy department at Columbia University. Unless you plan on remaining alive for a 100 billion years.

HELFAND:

This discovery has no practical meaning to our lifetimes... What it does mean is that we've relatively recently in the universe's history passed a point where in this gravitational slowing of the expansion has been overtaken by the dark energy's acceleration of the expansion and we're doomed to a very cold, dark, and empty future indeed.

NARR:

Helfand is talking about a lonely universe a 100 billion years from now. By that time dark energy would have expanded the universe so that galaxies we can now see through the hubble telescope would have receeded further and further apart till we can't see or study them anymore.

But while this discovery probably wouldn't affect most of the population on a daily basis, it has had an immediate affect for astronomy student Mark Dijkstra.

AMB:

telescope sounds

NARR:

He and his supervisor have been studying early stars.

DIJKSTRA:

It's quite impressive when I first started studying in 1995... dark energy... it was not even in the text books...and now 8 years later we measured the dark energy content to like 5 percent precision... I think that's really incredible.

NARR:

And for the non-astronomers amongst us? If nothing else, this discovery is a grand glimpse of where we've come from and perhaps where we're going.

Piya Kochhar, Columbia Radio News.