Causality is a deceptive concept. Sure, in the abstract – if this, then that – it’s clear enough, but sometimes when you start slotting in specifics it all gets very weird.
Try this, for instance: If an S-shaped twisted bundle of magnetic fields forms just above the surface of the Sun, then a currency trader in Geneva will lose several million bucks in seconds flat.
There are a couple of intermediate steps in there as well, but basically that’s the gist of it. It is a matter of sufficient importance – and sufficiently high probability – that in 2016 Lucie Green, solar physics professor at Britain’s Mullard Space Science Laboratory, found herself commissioned by some expensively besuited types to figure out how to prevent it.
The result was a co-authored paper with the faintly surreal title of Building Space Weather Resilience In The Finance Sector, and the memory still makes her laugh.
“I guess it’s my own fault, because I follow my nose and tend to do things that I’m interested in, rather than follow a five year plan,” she says.
“So working with the finance sector was completely unexpected – really interesting, though! It’s a completely different world to the academic one in which I live, but what was really nice was that it was a chance to take the science I’d been working on and then apply it to a real life situation.”
The science, in this case, concerned coronal mass ejections (CMEs) – huge explosions of magnetic fields and plasma that spasmodically erupt from the Sun and rampage through the solar system. Travelling outwards at anything up to 3000km per second, they expand as they go.
Really fast CMEs can reach Earth in as little as 14 hours. The shock wave embodied in several billion tonnes of high-speed solar particles can cause havoc with the planet’s magnetosphere.
This, in turn, can disrupt power grids, cripple high frequency radio communications, and royally stuff satellite derived GPS systems. All of which can send global banking, funds transfer, and stock market networks, which depend these days on split second timing, into meltdown.
A January 2017 study by the American Geophysical Union calculated that a solar storm-created blackout could cost $US41 billion per day in the US alone.
As tenured roles such as Professor Green’s amply testify, there are many things still to be understood about the physics of the sun, the cause of CMEs prime among them. One thing seems clear, however: S-shaped twisted bundles of magnetic fields have a lot to do with it.
“These get called ‘sigmoids’ by the solar physics community, and they’ve been seen on the sun ever since the Skylab mission in the seventies,” she explains.
“These s-shaped structures are really interesting because when you see them on the sun they have a very, very high likelihood of erupting as a coronal mass ejection, so there’s something about them, about their structure, that means they are eruptive.
“We’ve known that since the 1990s, but we didn’t actually know what they were. But with modern observations, we’ve been looking at how they form, and we realised that it’s all to do with the magnetic fields in the sun’s atmosphere. Everything you see in images of the sun is structured by magnetic fields.
“The sun has this electrically charged gas and it’s trapped by the magnetic fields. So it gets sculpted, and one of the sculptures is this s-shaped structure. So it’s like a rope of magnetic fields – and it’s a structure that likes to erupt.”
Much of Green’s current research is focused on uncovering exactly why these twisted magnetic bundles like to go off like humungous two-bob watches. It’s a quest that began with a bang – or a flare – many years ago on a work experience trip to Europe.
“I was an undergraduate at the time at Sussex University, and I was doing astrophysics,” she recalls.
“We went over to Crimea to do a work experience project, where we studying so-called high mass X-ray binary stars. During that trip, the people in the observatory were quite keen on having us look through all their telescopes, but no one was really interested in their solar one. So I went off by myself to have a look.”
The instrument in question used a hydrogen-alpha filter, which isolates a deep-red section of the visible light spectrum, allowing a detailed view of the atmosphere just above the surface of the sun.
“It gave me my first view of the sun in any way other than just the sort of day-to-day-yellow-disc-too-bright-to-look-at sort of thing,” she says. “To actually see the sun directly – where you can see columns of gas, snaking structures, dark areas. When I saw that I was completely intrigued, and that set me on the path to doing the study that I do today.”
Much of her work, if you’ll excuse the pun, constitutes blue-sky research. Unlike many of her colleagues in astrophysics, however, she is perhaps somewhat protected from the current populist turbulence that favours downgrading any investigation that isn’t immediately applicable. After all, she has friends in high finance these days, and that probably counts for something.
That doesn’t mean she isn’t worried about the future, however. “It’s an interesting time at the moment. There’s an economic return on blue sky research that can never be expected, but the thing that worries us at the moment is Brexit, and losing EU funding,” she says.
“It’s also about losing the people and the teams that we need to make good science happen. You need a diverse range of people – you can’t just have people who think like you, and have been trained like you. You need people from opposite sides to come together and challenge and have that robust debate in order to progress ideas and knowledge.
“There are definitely uncertain times ahead, but, I don’t know, scientists have a way of problem solving.”
Lucie Green will visit Australia and New Zealand during March and April 2017 as a cast member of Cosmic Shambles Live, a science variety show compered by UK comedian Robin Ince. Other guests include physicist, author and BBC documentary presenter Dr Helen Czerski, and comedians Josie Long and Matt Parker. Tickets and more information are available here.
