Masking Telescope

Reporter: Jonica Newby
Producer: Caoline Penry Davey
Researcher: Lucy Andrew

Transcript
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11 August 2005

Transcript

Narration: When you're surrounded by a typical Australian physics department, it's easy to see why your thoughts might drift to the heavens ...

... to dream of seeing things no human has ever seen.

Peter Tuthill wasn't just searching for any old star - he dreamed of finding one of the rarest; the Wolf-Rayet; the stellar dragon.

Dr Peter Tuthill: They're big and powerful. They're maybe five or six times hotter than our own sun. And they breathe fire. They actually breathe fire. They have these immense powerful winds and they puff smoke, yeah they're dragons.

Narration: But like any good quest, Peter was about to face some serious obstacles. First, a barrier that had frustrated astronomers for centuries. It's called the atmosphere.

JN PTC: Now don't worry - we're not trying to invite you to a physics party. We're just trying to create a little atmosphere.

JN: So how's this like the atmosphere exactly?

Dr Peter Tuthill: The atmosphere's a turbulent column of air and it distorts our ability to make clear pictures of the starts. It's why stars twinkle. And we're creating an exaggerated version of the atmosphere by looking at the heat coming off this barbecue. You can see the image is very distorted:

JN: Oh yeah. So that's what the atmosphere does to your vision of the stars - how annoying.

Narration: It's an annoyance modern humans have gone to extreme lengths to get around.

The Hubble telescope has been placed in space.

Our massive earth bound telescopes use flexible mirrors and complex software to compensate constantly for atmospheric distortion.

Despite costing billions, none have managed a close enough look at a Wolf - Rayet.

Dr Peter Tuthill: We've just had this fuzzy shimmering blobs and we've had to try and guess what they look like.

Narration: But then Peter thought: forget the futuristic technology - what if the secret to seeing dragons lay in the past?
He decided to try a bit of time travel.

PTC: This is Sydney Observatory and this telescope was built in the 1870's. Isn't it stunning.

Narration: Even if it does look a bit like a Dalek.

In 1868, a man called Fizeau came up with an unusual method of atmospheric avoidance. He made a little mask - a bit like this one.

Dr Peter Tuthill: You can see it's really simple its just got these two holes and its simply mounts on the front of the telescope like this.

Narration: It works like this. Imagine a choir, where each singer is like a beam of light. Put the atmosphere in front though, and they're all out of sync.

But the mask removes most of the singers.

Dr Peter Tuthill: It's much easier to then pick out a couple of singers - a couple of rays of light - and to get them in perfect harmony.

Narration: Whereas Fizeau used his eyes, Peter found he could harmonise key light rays coming through the mask using modern computing power.

He designed a sophisticated mask - it cost all of $100. Now for his biggest challenge - convincing a whole lot of guys in Hawaii to lend him their beautiful hundred million dollar Keck telescope, and let him put his little Aussie invention on top.

Dr Peter Tuthill: Firstly they thought I'd take my big heavy mask and drop it on something and break something.

And the second thing I had to convince them of was - I'm taking the world's biggest telescope and I'm turning it into one of the world's smaller telescopes. So persuading people that this wasn't a silly idea was actually quite challenging.

Narration: But eventually, the Hawaiians let him in.

Later, back in his humble physics hovel in Australia, Peter crunched the numbers.

He began to home in ... past the Hubble images ...

And there, astonishingly, the worlds first clear view of a dragon.

Dr Peter Tuthill: Oh the first picture of the wolf-rayet - I actually believed we must have got something wrong. We saw this amazing little spiral thing. And I thought there's just got to be something crazy here. There's no star that looks like a spiral.

Narration: But it was - a bright star with a spiral tail.

What's more, for incredibly small but bright objects like a Wolf Rayet, Peters old fashioned masking method gave 5 times the resolution of the Hubble telescope.

Dr Peter Tuthill: Astronomy is very driven by technology So to beat a lot of really high tech modern approaches with this relic, with this dinosaur. It's been a lot of fun.

Narration: It just shows if you dream of exploring the universe sometimes it pays to look to the past.