An innovative plan by Irish scientists to provide an early warning system for the arrival of solar storms powerful enough to disrupt critical infrastructure on Earth — using six tiny satellites each the size of a Jenga set — has received European Space Agency (ESA) backing.
The sun regularly produces solar eruptions in the form of flares, or bigger solar storms, which then travel rapidly across space and disrupt navigation systems, radio communications, power grids and spacecraft instrumentation upon reaching the Earth’s atmosphere.
The Surround mission, a collaboration involving scientists at the Dublin Institute for Advanced Studies (DIAS) and engineers at the University of Manchester is to explore new ways to reliably track and precise direction in which a solar storm is travelling.
Scientists understand that whether the storm’s magnetic field is pointing upwards, downwards, left or right determines whether it has a minimal or large impact on Earth. A major problem now is that because solar storm prediction is unreliable there are a lot of “false calls” on how impactful a solar storm will be on reaching us.
“What we particularly care about is trying to triangulate their position and tracking [solar storms],” says Prof Peter Gallagher, head of astrophysics at DIAS and its lead space weather research investigator. “You can then work out accurate arrival times at Earth; that’s the holy grail.”
The size of solar storms varies, says Gallagher, but some can be many times the size of Earth, and completely envelop the planet. “If they give us a glancing blow, they are not as effective, or ‘geo-effective’ we call it. If there is a full head-on impact, they will envelop the whole Earth, cause the Aurora Borealis, and problems with shortwave communications and GPS.”
When solar storms erupt they fire off electrons and protons held in a superheated gas (or plasma), which is carried across space by a solar wind — a stream of particles travelling from the sun at about a million miles per hour. The storms are a health hazard to astronauts and flight crews flying over the poles, where their impact is greatest.
The range of negative effects that can arise from Solar storms means mitigating such hazards is increasingly seen as crucial for human health. The best way to do this would be through a new, innovative method to better track and monitor then in real time.
The Surround mission is proposing to use a constellation of CubeSats to better track, monitor and predict solar storms. The plan is to launch six CubeSats, each with radio spectrometers to track the solar radio bursts associated with solar storms that can disrupt our global navigation satellite systems by interfering with radio waves. The CubeSats, which will each sit in separate locations in space, will combine to track solar storms from multiple angles.
“The proposal of using multiple satellites to observe the sun is to be able to triangulate where these kinds of ejections are coming from much better than we can with a single spacecraft,” says Dr Ciara McGrath, an Irish lecturer based in Aerospace Systems at the University of Manchester, and a Surround collaborator.
“The benefit of being able to use these really small spacecrafts is that it will be much cheaper to carry out that mission, because the smaller they are, the easier and cheaper they are to manufacture and launch,” says McGrath, who formerly worked on Scotland’s first CubeSat, a decade ago, while at the University of Strathclyde.
Up to recent years, spacecraft tended to be big, once-off projects that might take 20 years to design, build and launch. The downside to the amount of time this took was that when a craft was finally launched, much of the technology it had on board was out of date.
Another issue with the traditional approach, was that missions were expensive, with large communication satellites, for example, often costing about €1 billion. This meant any mishaps carried huge financial penalties. “It’s a kind of one shot: if something goes wrong you have lost the entire mission,” says Gallagher.
The cost of launching a CubeSat is minuscule in comparison: about €600,000. They are easy to work with, because they are now all standardised to the same shape and size, as are the electronics on board. This means more science can done with smaller budgets.
“With CubeSats, the development cycle is faster,” says Gallagher. “You get a lot of off-the-shelf equipment that allows you to do things much more quickly and cost-effectively.”
The smallest CubeSats are just 10cm³ but the most common size now is 30cm x 10cm x 10cm, which is about the size of a Jenga tower. The CubeSats are fragile, and can be lost, but this is factored in, and missions are designed to continue despite some CubeSat failures.
“We can start to have a supply chain of manufacturing rather than it being a one-off bespoke mission,” says McGrath. “You can do this more quickly and cheaply because you can put these bits and pieces together to create the mission that you want. That makes [possible] a lot of things that wouldn’t have been possible in the past.”
CubeSats also offer an opportunity for Ireland to take leadership of space missions. “For a small country it’s hard to take leadership in some of those bigger missions,” says Gallagher. “They are so pricey that is usually the larger European countries that lead them. Now, you don’t have to have these expansive budgets to design something from the start, develop it and then see it launched.”
The cost of launching CubeSats can be reduced through so-called “piggyback launches”. This is where CubeSats effectively hitch a lift on-board a rocket carrying a big spacecraft, such as a new GPS satellite into space. Then there is the option of Rocket Labs, New Zealand, the first company specialising in small, cheaper launches.
DIAS and the University of Manchester together applied to the Open Science Innovation Platform; a programme initiative by ESA aimed at developing the space innovations that Europe is going to need over the next few decades. They were awarded funding to conduct a feasibility study, which began in May. The initial plan is to focus on defining the scientific questions underpinning the mission.
“Then we will work with Ciara McGrath’s team to work out what does the spacecraft need to carry on-board,” says Gallagher. “Where does it need go? What kind of communication systems does it need? We’ll work out the technical requirements of the spacecraft that will allow us to do the science we want to do.
“By the end of 2022 we’ll have a high-level description of what the system is going to be like. That will be brought to a meeting of the European Space Agency at the end of the year. The science ministers will decide on whether or not we get a phase one, which is our next step, which will advance the concepts.”
The ESA has launched a new space safety programme. This includes support for research to reduce the risk from space junk left by human activities in space, or even microbes in space that might be a threat to human health. The threat from solar storms also comes under the programme, yet Ireland has not yet signed up to join, which Gallagher believes is a mistake.
“The UK have put a substantial amount of money into it,” he says, “They have said that space weather is a really important area for them, and they have it on their risk register along with ... pandemics. For the UK there is also the military application of space weather as it’s important for military operations and communications to know what is happening with space weather.”
“For Ireland, there are other reasons why it’s important: it affects shipping navigation and power plants, for example, but there is a peacekeeping aspect to this as well. You need to monitor where people are for peacekeeping operations, and the Irish Defence Forces are keenly aware of the impacts space weather can have.”
The benefits to Ireland from DIAS’s work on Surround are huge, says McGrath, who has seen Scottish space industry grow rapidly since working on its first satellite CubeSat a decade ago.
“Since then, the Scottish space industry has grown and, proportionately compared to the rest of the UK, a higher percentage of Scotland is employed in the space industry than the rest of the country. It will be really exciting to see how Irish industry follows that kind of trajectory.”