DW-TV: Dr. Gabriele Schönherr, telescopes seem to get bigger and bigger. ALMA is an area of many dozen different single telescopes. How much bigger will you want to be? Will you ever come to an end?

Gabriele Schönherr: No, never. I mean, astronomers will always need bigger and larger telescopes just because you need a larger collecting area and you need a larger baseline and radio astronomy for better resolutions for images.

And what are the biggest telescopes you have today?

Well, it depends on which range you ask. In the optical it would be a single mirror of 8.4 meters but the planning of 40 meter mirror out of different segments right now.

And if you look at radio astronomy?

The Atacama Large Millimeter/submillimeter Array (ALMA), is one of the largest ground-based astronomy projects of the next decade.

Well, there the trick is to combine different telescopes like with ALMA and you can in principle do that just limited by the Earth radius and not even that because there have been experiments where you were combining also satellites to the Earth bound radio stations.

So, there actually is no end. You'll always get bigger and bigger of-course.

With ALMA you can actually look back in time towards the big bang and you get to times as twelve billion years back. Which range would you actually use to go back even further, towards the birth of our universe?

Light wouldn't be enough anymore. You would need to go to gravitational waves, because there's a certain point where the universe got visible. But you can see the echo of the big bang in radio astronomy.

That sounds complicated, then.

Yeah. It is. It's do-able.

Astronomer Gabriele Schönherr is fascinated by big telescopes.

You are actually working with a project called LOFAR and the detectors or the telescopes you have look very different because they are very simple. How do they actually work?

Yean, I mean, you see here another next generation radio telescope like ALMA. Maybe you wouldn't believe it, it looks so simple. It's just one meter forty high antenna stations but the trick is that you combine all these different antenna fields, thousands of antenna, all over Europe in a computer, you digitalize the data, and you need one of the best super computers right now in order to combine it, so the real thing is the computer power behind it.

Amazing. Thanks a lot for the talk.

Interview: Ingolf Baur