On Wednesday 20th May, Dr Caitriona Jackman from Physics and Astronomy, and Dr Angelo Grubisic and Alexander Daykin-Iliopoulos from Astronautics will be at the Avondale House talking about mankind’s adventures through the Solar System.
Caitriona Jackman is a lecturer in the Space Environment Physics group, whose primary research is focused around the gas giant planets, Jupiter and Saturn, and particularly their magnetic fields. On Wednesday, she will be talking about the planets of the solar system, why they’re different, and what makes each one special. She adds “I have a few props – they say for ages 5+, so they’re probably suitable for adults who’ve had a bit to drink..” She’ll also be explaining how we know what we know about the planets, and talking about the many spacecrafts we currently have orbiting all of them, from Messenger, which recently ended its 11 year mission by crashing into Mercury, sending back its final images of its surface, to New Horizons, launched in early 2006, which is just now reaching Pluto and taking its very first, very fuzzy images of the distant dwarf planet.
Dr Jackman is not new to public engagement and giving science talks to wide-ranging audiences, having spoken before at free Stargazing Live events open to the public held by the physics department here on campus, which are very popular, and at Winchester Science Centre’s monthly Space Lectures, as well as appearing on BBC Breakfast and Sky at Night. She says this is a big part of her job, which she really enjoys, and she also focuses on trying to increase the number of women in her science, as something she feels quite passionately about.
To describe how we know things and find things out about our Solar System, she says, she uses an analogy to Masterchef: “In one of the challenges, a chef makes the contestants a fancy dinner, and they have to taste it, try to figure out its ingredients, and then recreate it. That’s pretty much what we’re doing – we look at the evidence, try figure out the ‘ingredients’ of the Solar System and how they combined, and then try to match theory and data, sometimes using models to ‘recreate’ it”
Caitriona did a general physics undergraduate degree in Ireland, which included a year long work placement which she completed at a space science lab run by UCL. She loved it, saying “It was a good way to test that it was what I really wanted to do – some people go into an area and then realise it’s really not what they thought, but this was exactly what I thought and even better!“ She then did a PhD at the University of Leicester, looking at data from the Cassini spacecraft mission to Saturn, following which came four and a half years of postdoctoral research at Imperial and three at UCL – during which she branched out from researching Saturn to comparing other planets, always looking at planets with magnetic field, as her specialism – and then came to Southampton in 2013.
Caitriona says she wakes up on Monday mornings and looks forward to coming to work. “One of the great things is working with really smart people, it’s an inspiring atmosphere to be in, surrounded by people who are interested in learning. I find scientists to be people who are interested in how things work and finding out answers. Pretty much everyone in academia stays because they love the research, so the colleagues are a big plus“
Like Dr Jackman, Dr Angelo Grubisic also joined the UoS community in 2013, having previously worked as a systems engineer for Qinetiq, and been responsible for developing the electric propulsion system on a £1.1bn ESA project. His research is in in-space propulsion, with devices called ion thrusters. These work by creating a plasma, or ionized gas – a gas made of (positively) charged particles – by stripping atoms of their electrons, and using another positive charge to repel the charged particles out of the exhaust, creating thrust. They are also known as Hall effect thrusters.
On Wednesday, Angelo will be talking about something entirely different; could we survive a mission to Mars? He will talk about the effects on the body of being in space, particularly for extended periods of time, which we have been able to study through having astronauts at the International Space Station. The human body has evolved to live in Earth in environments, with Earth gravity. Being in microgravity means your legs no longer have to support your weight to get around, and your bones lose a significant amount of their mass; your muscles weaken, including your heart, which decreases in size due to no longer having to pump blood against the force of gravity. Astronauts travelling to Mars would be experiencing this for longer than anyone has before. Dr Grubisic will also discuss the possible countermeasures which could be used to minimise these effects.
Joining Caitriona and Angelo is Alexander Daykin-Iliopoulos, PhD student in electrical engineering, working, like Angelo, with ion thrusters for in-space propulsion. He is looking at neutralisation devices. Ion thrusters repel ions through an exhaust with a like charge; when doing this for a little while, Alex explains, there is a significant build up of charge in the exhaust plume that means some of the ions are attracted back to the spacecraft, which is neutral overall. This means there is a decrease in thrust, and more fuel must be used in order to create the same amount of thrust. More fuel makes a spacecraft heavier, and more expensive to launch. Alex is working on improving an existing model of a device that ejects beams of electrons, separately from the thruster, into the plume of ions, to neutralise it and reduce the number of ions being attracted back to the spacecraft and slowing its acceleration.
Alex’s talk will be looking at accessibility to space, focussing on the amount of space debris surrounding the Earth, and looking at possible preventative policies for future satellites, such as pushing more distant satellites out into “graveyard orbits” with remaining fuel at the end of their lives, and burning up low-earth orbit satellites in Earth’s atmosphere after use. He will also look at ideas for remedial solutions, using “dustbin truck” satellites specifically to attract and secure other out-of-use satellites to then burn up in Earth’s atmosphere.
Caitriona, Angelo and Alex will be at Avondale House on Wednesday 20th May