The World's Largest Telescope

Well, radio telescopes are

nothing more than very big antennas.

That we aim at the sky instead of

trying to pick up the local top 40 AM station.

These antennas are aimed at the sky to pick up any

radio waves coming from distant parts of the cosmos.

And the Chinese have built the biggest of them.

You can bet that that telescope is

destined to find new stuff.

The largest single dish antenna, that was down in

Peurto Rico, it's called the Arecibo radio telescope,

had a 300 and some, 305 meters across.

It's been used to study galaxies,

and try to find out how fast the universe is expanding.

It's also been used for SETI research; in other words,

the Search for Extraterrestrial Intelligence.

The one in China is bigger.

It's 500 meters across,

a half a kilometer, okay.

And what it means is that it can look out into space,

something like 70 percent farther than Arecibo could

at the same sensitivity level.

Because it's such a big antenna,

it can find very very faint radio signals,

including those that might be being sent by,

I don't know, Klingons trying to get in touch.

I think that this can help SETI a great deal.

For example, Tabby's Star which has been in the news.

This is a star that's very peculiar,

the light from this star seems to dim.

Maybe there is some society on a planet around that star,

that's built an alien megastructure,

that occasionally blocks the light.

Well maybe, but I think that the history of astronomy

teaches you that no matter what you

think you're going to find with a new instrument,

it usually pales in comparison to what you

find that you didn't foresee.

There's no doubt that it's going to do

what all new, big telescopes do,

and that is to make some major discoveries for sure,

and increase our understanding of things

that we already know about.

And maybe, even find E.T.