Understanding near space

An Interview with Minna Palmroth, by CSC, the Finish IT Center for Science

This post was first published on the CSC website.

Minna Palmroth and her team have developed the most accurate space weather simulator in the world – a model that shows us how solar wind affects us.

Why doesn’t the water under bridges freeze?

Why do trees get covered in glaze ice?

How do streams flow?

These were questions that Minna Palmroth asked her parents and teachers when she was small. These days, she knows the answers to them all. She can explain how the world works, and also how near space works.

Minna studies space weather. The simulation model created by her team is currently the world’s most accurate model for describing how solar wind affects conditions in Earth’s near space. Minna and her team have quite literally revolutionised near space research.

Minna’s screensaver shows a series of summer cottage photos: the forest, a small lake, a wilderness cabin. But she opens her small laptop instead. “All my research is in here. If I lose this, I’m in trouble.”

Minna’s office is in the Finnish Meteorological Institute in the Kumpula district of Helsinki. A few cards and children’s drawings sit on the windowsill. Outside, the pines are bending under the sleet. On the wall, there are some colourful A3s that could be pieces of abstract art.

“They’re from Vlasiator.”

Yes, Vlasiator. When Minna got the idea for a next-generation space simulation programme, no one believed in it. She talked and talked, tested the idea on her colleagues.

“It won’t succeed.”

“No machine in the world could run it.”

“Way too difficult.”

But this just spurred Minna on.

“Things need to be genuinely challenging for me to be interested in them. Back during my schooldays, one of my teachers told my dad how strange I was – I only ever showed interest when I heard something was difficult.”

Minna submitted a funding application to the then recently established European Research Council (ERC). The ERC received 10,000 applications. 300 applicants received funding. Minna was one of them.

Understanding the future

It was 2004. Minna had just returned to Finland from the University of Colorado Boulder, where she had spent some time as a visiting researcher. Whilst there, she had been discussing current models with her colleagues – how they didn’t produce the physics that they needed to get a sufficient understanding of how near space works.

Creating a new model would, however, be difficult – otherwise someone would have done it already. When she got back to Finland, the idea got Minna thinking: it would be enough if she were to create a model with even slightly better physics than the existing ones.

She tested the idea on her colleagues. No one believed in it.

Except the ERC. One of the criteria for being awarded funding was that the project should lead to a major leap forward in science: high risk, high gain.

“What I suggested would constitute an incredibly huge leap forward.”

In her application, Minna wrote that she intended to build the world’s first high-resolution model and run it so that ‘the simulation would model the entire magnetosphere’. That is, the simulation would not examine the effects of solar wind from a single point only – it would show the whole picture.

When she submitted her application, there wasn’t a single computer in the world that would have been powerful enough to run such a model.

“My point was that it would take a few years to develop the model, and during that time computing power would increase, in accordance with Moore’s Law. If I seized the iron that was hot at the time, it’d be cold and obsolete by the time my code was ready. I had to seize the iron that would be hot when my code was complete.”

So Minna applied for funding on the basis of what she’d be able to use in the future.

“People don’t usually think like that. Physicists usually consider only the resources that are available to them now, not those they’ll have in the future.”

Minna needed the right people to accompany her on this daredevil journey. The kind that had enough personal courage to set out into the unknown. The first key addition to her seven-person team was researcher Arto Sandroos. Then CSC got interested in the project.

“CSC was thrilled by the idea that, what the hell, she’s doing something that isn’t possible with today’s computers. They said, good, no one usually thinks that way. They too were interested in future technology. So it was a win-win situation. We brought a new perspective on physics, CSC provided the technology.”

CSC’s parallel computing guru Sebastian von Alfthan joined the project. In retrospect, Minna realises that they’d been standing on the edge of the precipice the whole time, always one step from failure. Minna was risking not only over a million euros, but also her credibility as a researcher.

“I wasn’t interested in all the myriad ways in which things could go wrong. I was interested in how we could achieve new things. And that meant exposing ourselves to the risk of failure. I like to jump onto weak ice and see if I can swim.”

A hypnotising whole

Minna says that, before Vlasiator, doing solar wind research was like being a fish swimming around a stone.
She shows me some pictures on her computer: There’s the Earth, which has a magnetic field that extends into space.

Outside this magnetic filed you get solar wind, which is constantly being emitted from the sun. The Earth’s magnetic field blocks solar wind. Like a stone in a stream, with the current flowing around it.

A variety of interesting and hard-to-predict phenomena form around that stone, that is, the magnetosphere – and it’s these phenomena that Minna is studying.

Understanding near space has always been important: it affects the reliability of technology in satellite orbits and also, for example, electrical grid and geolocation technology. Therefore, before Vlasiator, we were like a fish swimming around a stone.

“At any one time, the fish can only see one point in the area surrounding the stone. If something happens where the fish can see it, it can’t know what caused it.”

Vlasiator can show us the whole picture: we can see every point around the stone and understand the causal relationships behind the phenomena we observe. We can see small-scale phenomena in a larger context.

Minna runs the Vlasiator animation on her computer. The waves of colour move and pulse, wax and wane.

“I could stare at this forever. Look at that there – watch that big blob go. And just look at those waves!”

“If I had the time, I’d start studying that,” Minna says, pointing out an orange tail. “Look, there it goes.”

It’s a phenomenon that causes rapidly intensifying, aka explosive, auroras. No one has discovered exactly what causes this phenomenon. It’s been measured since the 1960s, but remains a mystery. What makes auroras burn exceptionally brightly and change so quickly?

Minna has also stared this mystery right in the eyes. When she was 15, she spent the New Year at the Häme scouts’ cabin in Lapland. The cabin was in the middle of nowhere. It was pitch black outside – the only lights were kilometres away. One of Minna’s friends came inside and announced that there was an incredible display of Aurora Borealis going on. So they quickly put on their outdoor clothes and went outside.

They lay in the snow, staring up at the sky, where the green waves danced and pirouetted to an ever-faster beat.

Back then, Minna didn’t understand what she was seeing.

One of her friends happened to know it was caused by particles in the solar wind.

“I was like, wow.”

The second time Minna witnessed a rare corona phenomenon was at her wedding. It was September 2002. The wedding venue was an old farmhouse surrounded by fields. The reception began at six in the evening. It was dark outside, but the sky was clear and full of stars. Someone spotted auroras outside.

Everyone went out into the warm autumn evening to marvel at them and the guests were overjoyed: even the auroras are congratulating you!

“As luck would have it.”

The language of aliens

Physics is the field of science that explains how the world works. It starts with atomic-level explanations and reaches all the way to a universal level. The same laws apply throughout.

“If you met a being from outer space, you could communicate with it by speaking physics, because that being must understand physics in order to have come here.”

Plasma physics is one of the most difficult fields in physics.

“You can’t isolate space plasma in laboratory conditions in order to perform controlled experiments. Every event is a sum of its history and environment.”

A space physicist must understand the sun and its mechanisms; must understand solar wind, how near space works and how it interacts with solar wind; must understand how the upper atmosphere works – and, of course, how space weather manifests itself on the Earth’s surface and how it affects technology.

At worst, space weather could cause catastrophes on Earth: stop air traffic, damage satellites, and shut down electricity grids and communications networks. The most powerful solar storm in recorded history was the Carrington Event in 1859. An English amateur astronomer was observing the sun just before the storm began. He noticed an enormous solar flare. The flare exploded and, 17 hours later, the telegraph wires started to spark and telegraph offices caught fire. Gold prospectors in the mountains woke up in the middle of the night because they thought it was morning – the auroras were so bright. Auroras were visible as far away as the Caribbean.

If a comparable solar storm were to surprise us now, both its direct and indirect impacts would be massive: people could end up without electricity, networks could go down. At worst, nuclear power plants like Fukushima could overheat due to a lack of emergency power.

It is these processes that Minna is studying, the ones that cause solar storms. She’s also interested in studying how Finland’s electricity grid would stand up to a storm of Carrington proportions.
But right now she doesn’t have the time. She has two million euros to use on a completely different study.

The best, better model

Mystical-looking drawings on the whiteboard in Minna’s office are accompanied by English words: physics, methods…
“That’s my next research topic,” Minna explains. “I copied that directly into my application.”

Her application went to the ERC and brought Minna’s research team a second huge chunk of funding. It’s rare to get funding from the ERC once let alone twice – that’s truly exceptional.

Minna will be using her new funding to put together a team whose goal is to build an even more accurate and more computationally optimised 3D version of her Vlasiator model.

This model will enable us to examine near space phenomena even more closely – we’ll be able to look under the stone as well.

Although Minna understands how the world works and how space affects it, she says that it’s easy to start wondering whether we can actually understand everything after all.

“Recently, I’ve been wondering whether our idea of near space is actually correct, as we’ve been observing it by dividing it into smaller and more easily understandable sections.”

Minna is silent for a moment.

“That thought shakes my worldview a little. I mean, is it really so that nothing is clear at all?”

Demarcation at least is difficult. You only have to look at the Vlasiator waves on the screen to realise how many things affect our magnetosphere. And how far away in space the initial cause of a phenomenon may be.

Explaining such a system as a whole is extremely difficult.

Minna’s eyes light up. “That’s good – difficult is good! At least I won’t run out of motivation.”

About CSC:

CSC is a Finnish center of expertise in ICT that provides ICT expert services at an internationally high level of quality for research, education, culture, public administration and enterprises, to help them thrive and benefit society at large.

We harness our expertise, networks and IT to boost our customers’ success. We work closely with our customers on a non-profit basis. The purpose of our operations is to benefit our customers. Customers receive solutions tailored precisely to their needs (not too large, not too small). Our own expertise evolves together with that of our customers, which is what a real partnership is all about.

We proactively seek out innovations and new services through international cooperation to benefit our customers. Our mandate is to keep Finland at the cutting edge.

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