3.3.4 Behind the scenes with Monica Grady

I’m Monica Grady, and I’m professor of planetary and space sciences at the Open University. I’ve been doing research on meteorites and things that fall from the sky for over 30 years, which is a frighteningly long time when I think about it.

Monica is part of the Open University’s contribution to Rosetta; a ground-breaking mission which aims to unravel some of the mysteries of the comets in our solar system.

It has been 15 years that I have been involved with the Rosetta space mission. My particular involvement is in interpreting and understanding the data that are coming from one particular instrument on the Rosetta spacecraft, and actually it’s not an instrument on Rosetta, but it’s an instrument on the Philae lander which was released from Rosetta in mid-November

The near orbital levels of excitement in mission control said it all. A space probe landed on a speeding comet 300 million miles away; a feat some say is up there with the moon landings.

It’s just wonderful, it’s just, it’s just unbelievable, we’ve waited so long and now it’s happening.

It was a break of tension, it was just like we’d been in sort of just, it was like a wound up string, and suddenly it’s, it’s snapped, and all that energy, and it’s like yes fantastic, it’s happened, it’s happened, we’ve landed, and now, now the science starts and then you know after a few hours we start getting this er signal, we start hearing that well actually it didn’t land in quite the way we wanted it to, and then you start getting all tense and worried again, and then it’s like well actually yes we know where it is, we think we sort of know where it is and we think we sort of know it’s active, and we are getting data back from it, but it’s not quite where we thought it was, and it’s not quite in the way we wanted, it’s lying on its side under a cliff, instead of standing upright in the middle of a, in the middle of a flat plane. So, it didn’t quite go right.

When the solar system was made, comets were formed far enough out from the sun that they took in ice, er stuff that’s never been melted, and they haven’t been changed very much in 4567 million years. They’re time capsules of original stuff from the formation of the solar system, and that just in itself is interesting enough, but also we know that comets have bombarded the earth, er we know that comets are mainly ice, we know we’ve got a lot of water on the earth, we’ve been trying to test the relationship between the water in the comet and the water on the earth, you know, did, how much of the water has been brought by comets, and as well as that, comets have got a lot of carbon in them, organic material, the stuff that life is made from, the stuff that DNA is made from, those building blocks are present in comets. Could life have got going on earth if comets hadn’t delivered those building blocks to earth? We’re trying to explore that relationship as well, and that’s some of the really exciting stuff.

My work is mainly laboratory based and also uses data from space missions. One of the other things that we need to do though is to see what the objects that we are analysing look like when they are out there, so we need to take images of asteroids, and images of comets and we also need to look at newly forming stars, stars where there is lots of dust around them, where new planets may be being made, and so for that, we need a telescope.

Modern telescopes give us unprecedented views of space, but they aren’t always accessible, and successful research is always weather dependent, but the development of remotely operated telescopes mean these can be operated from anywhere in the world.

The Open University has a robotic telescope called PIRATE, which is sited in Majorca, so our undergraduate students get the opportunity to actually interact with a telescope in a way they might not otherwise do. The whole idea of operating a telescope remotely is that you don’t have to go there to switch it on, so I can do it from a computer which is running the software, and so I have it on my laptop, I can do it from work, I can do it from home.

When you start an observing program using a telescope, you’ve got to have your plan for what you’re going to be looking at in the night sky, and for your plan, you need to know where those stars are. To do that, you use a erm a software package, I’m using one called Stellerium or Stellarium, which shows you a map of the night sky. I’m going to click on the star Betelgeuse, so up here are the co-ordinates, we’ve got it’s right ascensions, 5 hours 55 minutes 10 seconds, declination, 7 degrees, 24 minutes and 25.6 seconds, so that’s Betelgeuse where the marker is.

Once we’ve opened the dome, you then have to make sure the cooler on the detector is cooled down to the right temperature, so that means we have to switch the cooler on. Betelgeuse, and we type back in those co-ordinates, so there it is, it’s got a telescope in the right place. Now it’s autofocussing, you know it’s checking if it’s right, the lens will begin zzzzuhh zuhh zuh zuh as it does when things auto focus, and here we are, in fact wow, there it is, there’s Betelgeuse, there’s the, the little star in the centre of the sky. I can zoom in so that we can actually see a bit more of this star, and it’s oh wow, it’s a very round erm bright white star. I can’t see much variation within there, I think that’s probably overexposed, I’m going to check that by taking a profile, going from one side of the star to the other, and you can see that has gone massively off scale, so that is completely over exposed, I’m not getting very much information from that, so what that tells me is that my exposure time of 5 seconds was far far far too long, so maybe I need to go down to an exposure time of 1 second, and astronomy is like this, it’s all a matter of trial and error.

Students can use PIRATE to observe and take images of stars, nebulae, comets and asteroids, and these images are then downloaded into software to be analysed.

Once you’ve got your data and you’ve downloaded it into a package that allows you to manipulate the data, then you can compare it with an image you might have taken of the same object yesterday, last week, ten years ago. You can look at a whole field of stars, not just an individual star, and looking at patterns of that field, compare it with that field from five years ago, maybe it’s different, maybe a star has become a supernova or something like that, so if you want to do really systematic work over, over many nights, these robotic telescopes are very very important for that.