It’s hip to be square

Like orbiting LEGO bricks crammed with tech, CubeSats are simple, (relatively) cheap, customisable and as Bianca Nogrady discovered, the next big thing for communications, real-time weather warnings and eyes in the sky. But how many is too many?

It’s risky business doing anything in space. It’s even riskier business scheduling a media interview to coincide with the assumed success of anything launched into space.

On 25 May 2017, Elias Aboutanios – Associate Professor with the School of Electrical Engineering and Telecommunications at UNSW Sydney – was supposed to be live on-air at the ABC in Sydney, talking about the successful deployment of UNSWEC0 which, along with two others, was to be the first Australian-built satellite to make it to space in 15 years.

UNSW-EC0 was a CubeSat, not much bigger than a loaf of sliced bread. Its outer surface was covered with the solar panels needed to power its brief three month lifespan, and it carried several pieces of specialised equipment whose purpose was to analyse and image Earth’s lower atmosphere and surface.

The three tiny CubeSats had launched in a rocket from Cape Canaveral just over a month earlier. Their transport had rendezvoused with the International Space Station, and on May 25 they were to be pushed out from the ISS, deploy their antennae, and commence communicating with the team.

Except they didn’t. Aboutanios and his colleagues urgently started trying to figure out why. “We work on the assumption that it’s not dead, and if it’s not dead, we work out what the possibilities are for it not talking to us,” Aboutanios says.

It turned out that during a period of storage before launch, the fully-charged batteries in the CubeSats had drained. Once deployed in space, its solar panels began generating electricity to recharge the battery, but certain software components had become stuck in a resetting loop, preventing the release of its antenna. Even stowed, the antenna could receive some signal – but not enough for technicians on the ground to reset the system using the small comms antenna they had access to at UNSW.

They needed a bigger, ground-based antenna to generate a more powerful signal. “We spoke to CSIRO, we spoke to Defence in Australia, we spoke to NASA,” Aboutanios says. Their white knight came in the unexpected form of an amateur radio astronomer in the Netherlands, who had access to an old radio telescope, but only on weekends. The first time he blasted the commands at the satellites, one of them – a CubeSat from the University of Sydney – responded. But UNSW-EC0 remained silent.

The team didn’t give up. Further digging revealed that their satellite had been mislabelled by NORAD – the North American Aerospace Defense Command – and they had actually been trying to communicate with the wrong one. A week later, they had another shot. The commands were sent, and finally, UNSWEC0 started talking back.

Telling the story more than three years later, Aboutanios speaks almost with fondness of what must have been a nail-biting few weeks. “It’s a massive learning experience,” he recalls. “You learn the things you’ve done wrong, you learn the things you’re good at. You have some amazing experiences on the way.”

Had this happened with a typical satellite, it would have been a tough hundred-million-dollar learning experience. Fortunately, CubeSats are cheaper, smaller, and far easier to build and launch. Even if the UNSW team had failed completely to awaken their sleeping device – as happened with one of its two companions – they no doubt would have picked themselves up, dusted themselves off and had another go.

At a barely $100,000 a pop, CubeSats are far cheaper than a typical Sydney house, which is why governments, states, companies, universities and even schools are putting their own satellites into orbit. Space has opened up, and the gold rush is on.

Hitting the payload

CubeSats belong to the “smallsat” class, in that they weigh less than 600 kilograms. In fact, at just one kilogram, a single unit CubeSat weighs way less – but that’s not even their biggest selling point.

“The idea with CubeSats is they have a standard,” says Iver Cairns, professor in space physics at the University of Sydney and director of CUAVA – the ARC training centre for CubeSats, UAVS (Unmanned Aerial Vehicles) and their applications. “They’re all approximately 10 centimetre by 10 centimetre by 10 centimetre cubes put together, there are standard electrical systems that people think would be useful, you can buy some parts commercially off the shelf, and that makes it so much easier to design.”

Several companies around the world sell standardised CubeSat frames – called the “bus” – and components, which makes it a relatively simple matter for those using them to add in their chosen payloads. “

The philosophy I like is that you buy the CubeSat bus and you put in the parts that matter to you, you put in the payloads, and you use your brainpower on the bits that are interesting to you, not on just the details of the engineering,” Cairns says.

The payload is the sexy stuff, and the reason CubeSats are so hot right now. They can carry a host of scientific instruments – imaging tech, radar, spectrometers, GPS, devices for measuring magnetic fields – all of which are being used to monitor and analyse Earth’s surface and atmosphere.

“Generally speaking, CubeSats initially were just a bit of a toy and people used them to test the capabilities to launch something into space,” says Adrian Rispler, CSIRO senior researcher and project lead on the CSIROSat1 CubeSat project. “But now the CubeSats are moving more into a scientific benefit space, people are trying to do proper science.”

At the University of Sydney, PhD student Savannah McGuirk has been studying soil carbon, a vital element of soil fertility. It’s also a potential source of income for farmers, who can earn and sell carbon credits by adopting agricultural techniques and practices that increase the amount of carbon sequestered in their soils.

Australia has a market for carbon credits in the form of the Emissions Reduction Fund, which includes credits for increasing soil carbon. “It’s really progressive legislation and there’s been two rounds of sales for the carbon credits so far; there’s a lot of interest, but still people are really struggling because it’s so impractical to measure and track soil carbon,” McGuirk says. “The process means going out in field, getting a soil corer mounted on tractor, taking soil samples and sending to the lab.”

This is where satellite-based imaging comes in. “In general, soil is darker when it has more soil carbon,” McGuirk says. “If you have a heavy clay soil it’s quite red, or sandy soil it’s quite yellow, but if you have a lot of compost and mix it in, the soil becomes a lot darker.”

Satellite images can give a broader picture of soil colour across an area of land: a single pixel in a satellite-taken image represents an area of around 10-30 square metres. Combined with ground-based measurements and unmanned aerial vehicle mapping, properly calibrated satellite imagery will enable farmers to build up a comprehensive survey of their soils.

And that’s just the starting point, McGuirk says. “Having those high-resolution soil carbon maps, you can look at climatic cycles, for example the effect of a rainfall event or prolonged drought. You can look at the effect of a government policy which gave landholders the right to irrigate for x megalitres.”

The CUAVA1 satellite, scheduled to launch in March 2021, carries a hyperspectral imager, which will provide a rich source of data for soil analysis. It’s also carrying a GPS instrument to study the Earth’s atmosphere by measuring the degree to which GPS signals are refracted as they pass through the atmosphere. That refraction is affected by temperature and water content, so the information is useful for weather forecasting. It can also be used to measure how GPS signals bounce off the surface of oceans, which provides information on wave height and direction.

“That gives you some information about the winds,” says Cairns, “but also damage that oil rigs, for instance, might obtain or whether a particular cruise ship should go this way or that way.”

CSIROSat1 is a three-unit, Earth-observing CubeSat expected to be launched in 2021. It will carry a range of instruments that will contribute to research on bushfires, tropical cyclones and more. Its hyperspectral camera can monitor the water content in tree canopies, which helps with fire-risk estimation, and can assess cloud formation to inform modelling of tropical cyclones. There’s also a strong business case for using it to look for mineral deposits of interest, particularly lithium and cobalt, which are in hot demand for lithium-ion batteries.

And while there are no plans yet for a successor to CSIROSat1, Rispler says a program called AquaWatch is in the early stages of development, with a view to using both satellites and ground-based sensors to monitor the quality of Australia’s inland and coastal waterways.

 But imaging even from low Earth orbit isn’t simply a case of “point and shoot”. It comes with unique challenges, such as jitter. “For CubeSats, you have a lot of vibration and you need to correct for that jitter in your images,” says Rispler. “If you think about a pixel in the ground, when that spacecraft is having some vibration, you create a swathe.” One of the skills CSIRO brings to the table is the processing needed to correct for the jitter, and to stitch the images together.

CubeSats are also expanding our understanding of the thermosphere – the atmospheric region around 85km to 600km above the planet’s surface, in which they orbit. Home to the ISS and other loworbit satellites, it remains relatively poorly studied because larger satellites can’t maintain orbit at such low altitude; atmospheric drag causes orbital decay far too quickly for such costly spacecraft. CubeSats, however, needn’t last as long, so they can orbit much lower.

The thermosphere is so-called because at its outermost edge, temperatures can be as high as 2000°C as the atmospheric particles absorb energy from ultraviolet and X-ray radiation, preventing them from roasting the Earth’s surface. It’s also vital for long-range radio and satellite communications, so understanding the mechanics of this region is vital.

A global collaboration of 28 countries – called QB50 – is planning to launch more than 50 CubeSats with the goal of advancing knowledge of the thermosphere; 36 have already made it into space, Aboutanios’ UNSW-EC0 among them. Onboard were three instruments: an Ion and Neutral Mass Spectrometer (INMS) to study the chemical composition of the thermosphere; a Langmuir probe, to analyse electrons there; and a magnetorquer to study magnetic fields.

“So you have the chemical elements, the electron content and the magnetic field,” Aboutanios says.

CubeSats are also shaping up to be a big player in the communications arena. At Australian company Fleet Space, co-founder and CEO Flavia Tata Nardini’s vision is to launch a constellation of 100 nanosatellites – not exactly the same dimensions as CubeSats, but a similar size – into low-Earth orbit to connect to the growing Internet of Things: smart devices in everything from home electricity meters to cars to telephone poles to heavy machinery.

“There is an explosion of sensors that needs to be supported by overall internet that ideally comes from space, because space sees it all,” Tata Nardini says. “I thought: We’ve got this big revolution of the Internet of Things, this big revolution of smallsats that are decreasing the costs of space, let’s bring them together.”

 With four satellites already launched, Fleet Space is focusing on industries that have lots of assets “in the middle of nowhere”, such as energy companies. “Companies like this around the world have almost no visibility on their assets, so if they lose power because of a storm, they put people in cars to go there and check,” Tata Nardini says.

Smallsats offer a cheaper, quicker way to know what’s going on. Sensors on every pole and wire, on every gas pipeline, on every valve can be monitored in real-time via a global network of orbiting smallsats. A downed pole, a leak or a broken wire can be detected instantly, with repair services dispatched exactly where they’re needed instead of having to spend valuable time and energy trying to pinpoint where things have gone wrong.

At this relatively early stage of development, CubeSat research is also helping to design and build better, cheaper, more accessible CubeSats. Most are currently built around an aluminium frame, but for UNSW-EC0, the team took a different approach. “We decided instead of machining the satellite from aluminium and do high-precision machining, we were going to 3D print the satellite using a thermoplastic and see how that works in space,” Aboutanios says. “If that’s successful, it could speed up the production and prototyping of satellites because you can just 3D print the thing.”

The space race

 In military technology there’s “mil-spec”; a signifier that a product has met the standards required to survive in challenging military scenarios, such as combat zones. Once it has done that, it acquires “military heritage”.

 “Space heritage is even more harsh,” says Youngho Eun, a postdoctoral research associate in aeronautical engineering at the University of Sydney and CUAVA. There’s vacuum, extremes of heat and cold, and radiation, not to mention the violent physical forces a satellite is subjected to during launch.

Space heritage for a product is highly sought after, and the reason there is such a push to get components into CubeSats that are designed and made in Australia. “There are five to 10 companies that specialise in CubeSat structures and components,” Eun says. “They have this space heritage, so they have done several launches with their products.”

That gives those products a huge advantage, in both cost and desirability. Building up that space heritage for Australian technology is the end game, Eun says.

It’s easy to forget that Australia was actually a frontrunner in the early space race. In 1967, Australia became only the third nation to have designed and launched a satellite – WRESAT, the Weapons Research Establishment Satellite – which was sent into orbit from Woomera, South Australia. Yet that significant achievement was all but lost to history as successive Australian governments pulled back from funding spacerelated research and development. Until recently, Australia was one of just two OECD nations without a dedicated space agency.

That changed with the establishment of the Australian Space Agency on 1 July 2018. One of its two key roles is to “support the growth and transformation of Australia’s space industry”. It’s a change from the more well-known paradigm of space agencies being the researcher, developer, builder and launcher of space hardware and software, says Anthony Murfett, Deputy Head of the Australian Space Agency. “We’re an emerging space nation looking at ways we can participate in big projects, and the way we can do that is by being a partner and facilitator.”

That means supporting Australian business to build up that space heritage so they can contribute to international space activities, and awakening sectors that might not have even considered their role in a future space industry.

Australian company Inovor has long had its eye on the space prize, having been building satellite technology since 2014. CEO Matthew Tetlow did his PhD in rocket guidance systems, and spent a long time trying to get anyone in Australia interested in launch vehicles. Frustrated with the lack of movement in that area, he pivoted into satellite attitude control systems and built a prototype; that design is now part of CSIROSat1.

Tetlow’s desire to develop space heritage isn’t just a matter of local pride; it’s about knowing every component of a spacecraft, inside and out. “Typically, universities and other groups buy a whole lot of parts from other people and plug them together and make a satellite,” he says. But the result is a bit of a “black box”. “You have no idea what it’s doing, so your ability to test and evaluate the system properly is greatly diminished,” he says. “The only way you can do this properly is if you actually know what’s going on.” Inovor is now building not only the attitude control systems, but the CubeSat bus – the frame – the power systems, and the command and datahandling systems.

“We can fly any payload; we can design a mission around payload using our modular components, we can build a spacecraft to suit other people’s payload,” Tetlow says. That has led to another first for the Australian space industry: an Australianmade spacecraft hosting a foreign-made payload. The SpIRIT (Space Industry Responsive Intelligent Thermal) CubeSat – a University of Melbourne mission, partnered with four Australian space technology companies – is carrying a payload from the Italian Space Agency. “It’s Australian-built and we’re able to put another country’s payload on it,” Murfett says. “That’s a really exciting development.”

There hasn’t been a successful rocket launch on Australian soil since the 1970s, but there’s now a push to revive this part of the space industry. Currently, Australian CubeSats are launched from places such as New Zealand and the US. But that could be about to change. Australian companies Southern Launch and DEWC Systems achieved the first successful commercial launch of a space-capable rocket in September this year, from the Koonibba Test Range near Ceduna in South Australia.

Traffic jams on the space highway

The gut-churning terror of 2013 science fiction film Gravity wasn’t just due to the nail-biting trials Sandra Bullock’s main character endured. It was also the scenario of spacecraft collisions in Earth orbit generating a lethal, fast-moving, ever-growing cloud of debris that shreds everything in its path.

This is the future that NASA scientist Donald Kessler warned about in 1978: the danger that increasing orbital debris would reach a density where it would effectively make those orbits inaccessible. Humanity would lose access to space.

Some are concerned the so-called Kessler Syndrome is already here. With companies such as Elon Musk’s Starlink launching more than 700 satellites into orbit – and planning thousands more – Earth’s upper atmosphere is getting very, very crowded. From 2012 to 2019, more than 1700 smallsats were launched, and in 2019 more than half of the nearly 400 smallsats put into space came from commercial operations.

“It’s a big area of concern for many groups, whether they’re governments or astronomers or other people interested in the night sky, or they’re actual companies or scientists trying to do something with data,” says Iver Cairns. It’s not just the collision risk; it’s also the issue of communication bandwidth. With that many satellites trying to communicate with their ground crews, it’s also very noisy.

Flavia Tata Nardini at Fleet Space anticipated this challenge early on and created a whole department to ensure the company successfully applied for a particular frequency to communicate with their satellites. They’re also developing technology to make the most of the frequencies they’ve been allocated.

But despite some loud voices to the contrary, this is no Wild West-style land rush, where whoever gets up there first wins, says Steven Freeland, professor of international law at Western Sydney University. First, there’s the 1967 Outer Space Treaty – the “Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies” – which was previously adopted by the UN General Assembly. “The Treaty imposes obligations and rights on the countries … to assure that those within their jurisdiction don’t do anything that would be a real problem in terms of the fundamental principles under the treaty,” Freeland says.

Again, Australia was at the vanguard when it developed its own set of national space laws in the late 1990s – it was only the sixth country to do so. But those were drafted long before smallsats came along. “There’s a registration process under international space law where essentially everything that’s launched into space is to be registered and then that information sent to the UN,” Freeland says. “When you’re sending out 60 satellites at a time, that makes it impossibly difficult to do on all sides.”

Anticipating the changing nature of the space sector, in 2015 the Australian government commissioned a review of Australia’s space laws – a process led by Freeland – and, following on from that initial review and further consultation, it has since released an updated set of laws designed to make the process more accessible to smaller operators.

But not all countries have the same rules, and Freeland warns of the danger of a “tragedy of the commons” situation unfolding in a worldwide business-as-usual scenario, where commercial interests drive a headlong rush that isn’t as wellchecked as it should be.

 “We all want to garner the benefits of space – there are great benefits that can stem from small satellite technology – but we don’t [want to] screw it up, because if we allow things to go beyond a tipping point by not preventing irresponsible behaviour, we will reach a virtually irreversible situation where our ability to access space is compromised for generations to come.”

The final journey of a cubesat

 It’s a wonderful feeling to put something into space, says Iver Cairns. “You have held the satellite in your hands, your arms, like a baby, and you and your team have agonised over it. To see it go up in a rocket from Cape Canaveral or wherever is a magnificent feeling – you’ve got the butterflies in your stomach, you’ve got the cold shivers. It is fantastic.”

 It’s a short-lived sensation, however, with smallsats lasting months to maybe a year or two. The atmosphere at low orbit drags on them, slowing them until they can no longer resist the Earth’s gravitational pull and they fall low enough to burn up, going out in the proverbial blaze of glory.

Aboutanios recalls the uncertainty of those last moments when it was UNSW-EC0’s turn to dive into the atmosphere. “It was strange because we couldn’t see it,” he says. “It was a bit like: Has it come down, has it come down, has it come down?” Its orbit sank lower and lower, until suddenly the spent smallsat disappeared off radar.

Though there were no celebrations, Aboutanios says that for a mission shaping up in its first weeks to be a sizeable failure, it was even more of a triumph than if it had succeeded without issue.

“If they had gone up and worked from the get-go, it would have been great,” he says. “But it wouldn’t have been amazing. The fact that they didn’t work and we revived them was 100 times more great and more amazing.