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Now, back in the seventies I was a student. There I was. Trying to look like John Lennon, I think. And there were not too many opportunities to launch satellites just for astronomy. So we did the next best thing, we used something called a sounding rocket. It's really a glorified Guy Fawkes rocket. You light the blue touch paper; the motor fires for about forty seconds and, if you are lucky, you go two or even three hundred miles above the Earth, above the atmosphere. And if you put your telescope on that and point it and do everything right you can do your astronomy in just a couple of minutes. Back in the early 1970s, after I got my degree, I found out that, if I went to London University, I could actually design and build telescopes to go on the sounding rockets. I could go to Australia, to Woomera, to the rocket range there. I could launch them and I could get a grant to do all of this. I mean, how lucky was I? The subject was X-Ray Astronomy. It was a new subject; the first x-ray source had only been detected about nine years before. The person who did it subsequently won the Nobel Prize for it. If only I had been a few years older maybe it would have been me.
So I was riding the crest of that new wave of astronomy. So I signed up and I was given the task to build a particular x-ray telescope. This is what we built. This is called an x-ray spectrometer. What it was going to do was take in x-ray radiation and split it up into the different x-ray colours and analyse how many x-rays there were in each of those colours. We were going to point it at a particular object called a supernova remnant. This had been a star. It had exploded cataclysmically, four thousand years before, and it threw out a vast cloud of material, which was still so hot that it was glowing – not in light – it was much too hot to emit light – it was emitting x-rays. And that was what we were trying to look at. So there we were at Woomera, a bunch of young scientists. Between us we had precisely zero years of Space experience. Luckily there were a couple of very experienced engineers on the project. I think they had been working for all of five years in space research. They were the veterans. Between us we got the instrument and the rocket to the launch pad. Now, in a minute I am going to play to you my recording of the last twenty-five seconds or so of the countdown. It's not a very good quality because this was an illicit recording. Woomera was a high security Ministry of Defence site so I had to smuggle the tape recorder in. Now, remember, this was my first ever launch. Let’s hear it. We were in a bunker about a hundred metres away, just under the ground, and at about minus fifteen seconds I had to make a decision as to whether we would launch or not. I’ve just said “Gas Okay, Jackie”. So that was the Okay. I was terrified. Everything crossed. That’s ten seconds to go, I think. Fingers crossed, toes crossed. Five … It was absolutely fabulous! I mean that sound, that blast wave went through your body. The rocket is already three miles up. It went up with enormous acceleration. It got above the atmosphere. The x-ray telescope pointed at the correct source on the sky to an accuracy of about a hundredth of a degree.
It was a very, very challenging task and it pretty well worked. Well, up to a point. I should say the data was sent by radio link back down to the ground, to the receiving station. And that was lucky because our luck ran out on the way down. The parachute should have opened so that our payload gently floated down. We could have used it again then on subsequent flights. Well, the parachute never opened. The payload hit the ground at about a hundred and twenty miles an hour. It was a mangled pile of metal. Still, I was able to get one small souvenir from that flight and I have got it here. I managed to smuggle it back under my jacket and I would like to show it to you. This is the nose cone from the rocket. This is one of two nose cones that fitted over the top to give it an aerodynamic shape so that it could get up through the bulk of the atmosphere. It was got rid of at about forty seconds by explosive bolts and it sort of fluttered down and landed on the desert floor. And so I managed to get that back home. It looked rather good. It made a difference from all the Che Guevara posters on the wall that we usually had. So what happened? Four years of designing and building this and then analysing the data. What was the result? Well here it is. You are speechless I know. But to me this meant everything.
This is what we call a spectrum. To my colleagues not a high-resolution spectrum I admit. And the critical part, which I am sure you have noticed, is this bump. That was it. That was the detection of oxygen from this particular super nova remnant. It was glowing; the oxygen was glowing and giving out one particular x-ray colour. I was very, very proud of that. It was predicted but it had never been done before. An element had never been detected by x-rays from beyond the sun. And we did that. So this was published in a journal called The Monthly Notices of the Royal Astronomical Society, a very prestigious journal. And it is one of the papers that I still look back on with some pride. I can't say that about all the papers that I have written, I have to say. Now, every good lecture I feel, as we all know, has to have a picture of a kangaroo. And here is mine. So why have I got a kangaroo? Well, rockets are actually quite dangerous objects. You know – lots of high explosive and there are all sorts of precautions that you have to take. And at Woomera they were very proud that in thirty years of operation they didn’t have a single fatality – well, at least a human fatality. There was one fatality and it was a kangaroo. Not this one. One of the payloads was found in the desert, was recovered and it was another mangled heap of metal. And about thirty meters away was a kangaroo – dead – absolutely dead. Not a single mark on it. And the assumption was that it had been sitting there, minding it's own business and this rocket had crashed down a few feet away from it and the poor thing had died of a heart attack. Poor old thing. Okay. Well, hopefully, the Woomera experience gives you some idea of how I fit in to the fifty years of space exploration. I had my first five minutes in space.
With thanks to:
- The Royal Astronomical Society
- National Geographic/Getty Images
The Open University Lecture 2007
This is part 3 of 10