Ready for the final showdown... bring on the questions!
Bulmershe School, Reading (2001-08), University of Southampton (2008- present) – including a year abroad at the Harvard-Smithsonian Center for Astrophysics, Boston, USA (2011-12)
A-Levels in Physics, Chemistry, Maths, History and German, AS in History and Further Maths, Masters degree in Physics & Astrophysics
I’m still technically a student, so I haven’t had any full time jobs… but I used to work part time as a lifeguard before my PhD!
PhD in Astrophysics, looking at black holes in other galaxies
University of Southampton
Favourite thing to do in my job I love talking to other people about new ideas and possible explanations for things we don’t understand
I’m trying to find out more about massive black holes at the centre of galaxies and how they suck up nearby gas
As the name suggests, black holes don’t give off any light, because their gravity is so strong that even light can’t escape being sucked in. The reason their gravity is so strong is that they are incredibly dense. The most common type of black hole would typically weigh about 5 times as much as the Sun, but only be about 30km wide, which is about the size of a medium-sized city. This makes it 100 million times smaller than the Earth and a hundred trillion times smaller than then Sun (that’s 100000000000000!), even though it’s heavier than the sun! The type of black holes that I study are much, much heavier though! They weigh between a million and a billion times more than the Sun, with sizes between about the same size as the Sun and a thousand times bigger.
You might wonder how you can find anything out about something that doesn’t give off any light, and the only way that you can is when other things in space, mostly gas, gets too close and get sucked towards the black holes. As the gas falls in, it makes a huge, swirling disk which gets very hot, and shoots out huge galaxy-sized jets of gas into space. All of this gives off a lot light, from the visible light we can see up to Ultraviolet and X-rays and down to Radio waves. All of this is watched by a huge range of telescopes designed to look at specific types of light. I mostly work with X-ray and UV telescopes, which have to be in space (like the Hubble telescope) to see anything, because the Earth’s atmosphere blocks most of the UV and X-rays from getting to the ground (luckily for us!). I also use radio telescopes, which are made of lots of huge radio dishes which all point at the same object in space at the same time, so that we can make pictures of things out of the radio waves coming from it.
Here’s a artists impression of a supermassive black hole with it’s disk of gas and jet shooting out into space:
The point of all this is to find out what happens to stuff that falls onto black holes and use that to work out how black holes work. Even though the closest black holes are thousands of light years away (billions of miles), it’s important to know how they work because they are so strange. It would be impossible to make something as dense as a black hole in a lab on Earth, so looking at black holes is the only way we can see what happens when gravity is as strong as it is around a black hole. This lets us test what we know about gravity to it’s limits, in particular the theory that Einstein came up with to describe it (General Relativity). If we didn’t know about this, things like GPS and satellite TV wouldn’t work, so it can affect you directly. It has also been found that supermassive black holes have a huge effect on how the galaxy they’re inside grows and develops, meaning they have a direct impact on how the whole Universe has changed over time. Plus, they’re worth looking at just because they’re really interesting!
The main ways we try to work out what’s going on around black holes is by looking at pictures and spectra (plural of spectrum) of them in different types of light. X-rays only come from the very hottest things, so they’re good at looking at things which are right next to the black hole, optical and UV light are good for looking at the disc of material which is swirling into the black hole, and radio waves come from the cooler gas further out, in particular the huge jets of gas that they shoot out. As the black holes are so far away, we can only see really big details of the stuff around supermassive black holes, even with our best telescopes – they’re mainly good for looking at the jets, which can be bigger than the width of the whole galaxy which the black hole is inside. Most of our information comes from the spectra.
Here’s an artists impression of NASA’s X-ray Space Telescope, called Swift, whose data I use a lot:
A spectrum is just the different colours in light split up, the same as a rainbow, when visible light is split by raindrops, or by a prism. By looking at how much of each colour there is in the light, we can tell things like what gases make up the surroundings of the black hole, how fast the gas is moving, how hot the gas is and whether there is anything blocking some of the light from getting to us. You can even sometimes work out things like how strong the gravity is or how powerful any magnetic fields are. When you piece all of these bits of information together, you can start to build a picture of what the gas around the black hole is doing, how big and heavy the black hole is, how much energy they’re producing and more!
Whilst we know quite a lot about these things, there are still a lot of questions which haven’t been answered yet. It’s my job to try and answer some of these questions!
My Typical Day
I spend most of my time on a computer analysing data from telescopes and trying to work out what’s going on around different black holes
As an Astronomer, space is my lab, so unlike a lot of scientists I don’t spend any time in a lab doing experiments. The black holes I study are my experiments, set up by the universe for us to study how it works, and telescopes are the instruments I use to measure it. Whilst some Astronomers would go to a mountain somewhere for a few weeks and collect some data themselves with a telescope, the telescopes that I use are in space, so I can’t do that! Instead, I ask for the telescope to be pointed at something I want to look at, then a signal is sent to the telescope in space and it automatically turns at looks at it, then sends the data back down to me electronically (via NASA or ESA, or whoever is controlling the telescope!).
A lot of my time is spent looking at telescope data (images or spectra) on a computer and trying to work out the physics of what is going on in the object I’m looking at. This involves things like writing computer programmes to do different things to the data, plotting graphs to see what it looks like in different ways and making computer models of what the black hole is doing, to see if the data fits my idea of what is going on. Once I have a good idea and some results that are worth sharing with other scientists, I’ll write a scientific paper, which is a report of what I did, what the results were and what I think the Science behind them is. This is then published in a Scientific journal, on the internet and on paper for libraries, so that other scientists and anyone else can read them.
Other things I often do during a normal day are read others’ papers to see what other people have previously found out about the thing that I’m studying at that particular time, sending emails to other people I’m working with, or talking to them if they’re in the same place as me.
I usually spend several hours a week ‘demonstrating’ which is helping to teach undergraduate university students Physics, helping them with the Physics questions they’re set, or programming, in the labs, or with Astronomy projects.
Every week there are presentations to go to by Astronomers from other Universities and institutes where they talk about the latest results and theories. I also spend a lot of time writing things down on paper and thinking of ideas to explain what I see in the data!
This is a picture of me in my office, at my computer, where I spend a lot of my time. I have two screens, so I can do twice as much work…
What I'd do with the money
Spend it on taking the University of Southampton’s inflatable planetarium to schools, to show people how interesting astronomy is and get people exited about it!
As well as doing my research, I quite often do various things to tell normal people about Astronomy, show them how interesting it is and why it’s a useful thing for us to be doing! This involves doing events like Science fairs and the BBC stargazing live event, but most often it involves going to schools for the day with our inflatable planetarium and teaching school students about what the space and what Astronomy involves.
Our planetarium is called the Southampton Astrodome and is basically an inflatable igloo which has a lot of fancy mirrors and equipment inside which let us project the stars and planets and everything else in space onto the inside. The fact that it is dome-shaped means that we can show you how the night sky looks just as it would do if you were outside that night, without any bad weather or light pollution or anything else that hides the stars! This lets us show you how to find things like the North Star and the planets when you go outside at night. We can also zoom in on all of the beautiful things that you can see in space, like galaxies and nebulas, so that we can explain what they are and how they work, and all the work that we as scientists do to find out new things about the universe that were previously unknown.
Here’s a picture of me and four other astronomers standing in front of the Astrodome at the Big Bang Science Fair for school students at the NEC outside Birmingham. We had shows all day there for four days and showed hundreds of people about Astronomy, and even had a real Astronaut inside!
As well as doing shows in the Astrodome, I sometimes do other things for the public and school children, to teach them more about space. Here’s me showing some students what the relative sizes of the planets are with playdoh (it’s amazing!)
And here’s me at the Winchester Science Centre , teaching some school kids about different types of light (with an infra-red camera!) during National Science Week:
How would you describe yourself in 3 words?
Adventurous, laid back, curious
What or who inspired you to follow your career?
I had a few great Physics teachers who all inspired me
Were you ever in trouble at school?
A lot for talking too much, sometimes for being lazy or not doing my homework
If you weren't a scientist, what would you be?
Who is your favourite singer or band?
What's your favourite food?
What is the most fun thing you've done?
I had a ride on an Ostrich!
If you had 3 wishes for yourself what would they be? - be honest!
A better memory, lots of confidence and lots of luck
Tell us a joke.
Three guys go into a pub. One of them is a little bit stupid, and the whole scene unfolds with a tedious inevitability.
These are some of the things I do on less typical day – go to conferences to give and watch talks by other Astronomers, and talk to them about their ideas and results, go to workshops to learn about how to use particular types of telescope, or do particular tests on the data I get. Astronomy is very international, and these events are often in different places around the world, so you get to meet a lot of people from different countries – I have friends in loads of different countries now, which is great!
Here’s me in front of one of 14 huge (25m wide) radio dishes that make up the Westerbork Synthesis Radio Telescope, when I went to a workshop about using radio telescopes:
Here’s me (and others) watching talks at a conference on supermassive black holes in Naples, Italy:
And here’s me giving my own talk, attempting to look smart! I only found out I was giving it the day before, to about 100 experts, and it was my first talk as a PhD student, which is why I look nervous!