Big Implications, Little Technology
How small satellites are revolutionizing space
Erica Sullivan/Los Alamos National Laboratory
On a clear morning in Sriharikota, India, in mid-February 2017, a rocket launched carrying a record-breaking 104 satellites, including 101 CubeSats.
CubeSats are nothing new. A type of small satellite comprising units measuring 10 centimeters by 10 centimeters by 10 centimeters, they were first developed at Cal Poly and Stanford universities in the late 1990s as a training tool for aerospace engineering students. (“SmallSats” by definition weigh less than 500 kilograms; so all CubeSats are SmallSats, but not all SmallSats are CubeSats.) It wasn’t long before governments began to look for ways to use CubeSats and other small satellites to bolster national security.
It’s no coincidence that the rise in interest in these smaller than a mini-refrigerator satellites coincided with the awareness that existing satellites were vulnerable. In 2007, China proved this when it used a missile to obliterate one of its own satellites. Then there’s the threat of cyber attack. The May 2017 ransomware virus that infected hundreds of thousands of computer systems around the globe and shut down hospitals and train stations was a stark reminder of the power of hackers. If that cyber attack was so debilitating on Earth-based systems, a carefully orchestrated cyber attack on a space-based asset would be catastrophic.
Virtually every military mission relies, to some extent, on satellites. Communications satellites enable joint force command and control by ensuring the availability of accurate, complete and timely information for the operational chain of command for land, sea and air forces. Meteorological satellites provide up-to-date weather information to field units in every branch of the military. Navigation satellites provide accurate positioning — within a few meters — for troops, planes and ships. Space-based surveillance systems provide treaty-monitoring capability during peacetime and serve as essential warning systems during conflict.
For the civilian arm of the government, satellite imagery is indispensable for disaster planning and response, mapping, urban planning and traffic monitoring. Then there are commercial uses: satellite phones, the internet, television, navigation and commercial tracking, resource exploitation — even predicting the weather for air travel or planting crops.
A successful attack on just one of those satellites could have far-reaching negative consequences on security and the economy.
What if, instead of one giant satellite providing critical national security functions, there were a hundred small satellites doing the same thing? The target would not only be smaller, but it would be dispersed — making a cyber criminal’s job significantly more difficult.
Small satellites offer a lot of advantages. First and foremost, they’re inexpensive. The average large satellite can cost anywhere from U.S. $500 million to U.S. $1 billion or more to build and launch. That’s a hefty price for any budget. Small satellites, by comparison, are a bargain.
For example, Los Alamos National Laboratory has built and launched several CubeSats and estimates production costs of about U.S. $150,000 per unit. Also, the less expensive hardware means more technology can be acquired — enabling greater geographic coverage for observation and detection missions such as Earth/wave movement, seismic and volcanic activity detection, and atmospheric measurements.
Furthermore, by using less expensive platforms such as CubeSats and SmallSats, space scientists can test advanced concepts such as reconfigurable computing in space. In the past, once a satellite was in orbit, there was little operators could do to alter it. For the lifetime of the spacecraft, its functions would continue to be what they were programmed to be at the outset. Not so with CubeSats, which space scientists have made reprogrammable to allow for mission changes and improvements.
It also allows for a more agile approach to space hardware. Constrained mission needs enable rapid, focused development. While a large satellite can take a decade to design and build, space scientists can do the same with a CubeSat in a year or less. They also enable more testing in the operational environment rather than in simulated environments on the ground, and they allow cutting-edge technologies to be incorporated as they hit the market. Instruments and components can be tested in space before they’re integrated into larger platforms for the final mission. These demonstration and validation missions greatly inform the design of instruments for any size satellite.
For these reasons, small satellites are revolutionizing the way scientists approach engineering space systems. A staggering 2,400 SmallSats and CubeSats will be launched during the next six years, experts estimate. Whereas in the past, the commercial, government and academic sectors have used SmallSats equally, commercial use is expected to leapfrog the rest soon. In fact, over the next three years, commercial use of small satellites is anticipated to account for more than 70 percent of launches.
Small satellites aren’t perfect. The majority, especially CubeSats, are launched to LEO and will re-enter the atmosphere due to drag much more quickly than spacecraft at higher altitudes — so their useful lifetimes are shorter. This is offset by the fact that getting to LEO is cheaper and easier and subjects the satellite to fewer radiation effects. Also, LEO allows the satellite to be closer to targets, improving the resolution of imagery, enabling lower-power communications and decreasing communications latency.
Increasingly, the government, industry and academia are looking for ways to use small satellites in orbits beyond LEO. For example, at Los Alamos, scientists and engineers are thinking of ways to use small satellites and CubeSats for deep space and interplanetary exploration missions. For these technically challenging missions, smaller, less expensive satellites create the opportunity to spread technical risk over redundant systems and to collect data from more locations.
There’s also the issue of limited launch availability. Small satellites are often constrained to the rocket equivalent of Uber: They must “rideshare” with bigger payloads. This limits orbit options and schedules to those set by the primary payload, which pays the preponderance of the launch costs. Launch delays and the lack of dedicated small satellite launch vehicles have constrained the market potential, creating a backlog of SmallSats waiting for a ride to space.
System reliability is another issue. A comprehensive database of missions shows that more than 40 percent of CubeSats launched since 2000 failed to accomplish their objectives — perhaps an acceptable rate for student engineering programs or experimental commercial systems, but a nonstarter for meeting national security objectives. The challenge is engineering a system with the reliability required from space assets, while keeping the costs for components and testing in line with the costs of small satellite and CubeSat hardware.
Limitations on data processes and regulatory restrictions are other challenges. Launches require extensive paperwork to demonstrate that the secondary payloads “do no harm” to the primary payload. Then there’s the concern over space junk and the consequent de-orbit requirements.
Perhaps the biggest challenge small satellites present is the very thing that makes them so appealing: their relatively low price tag. Because CubeSats and SmallSats are inexpensive (and the price will keep dropping as the technology advances), soon anyone will be able to access space, including adversaries for whom space has historically been out of reach.
For decades after the Soviet Union launched Sputnik, space was dominated by three nations: the United States, USSR/Russia, and — later — China. Increasingly, space is becoming more crowded. Today, satellites from China, the European Space Agency, France, India, Israel, Iran, North Korea, Russia, the United Kingdom, and Ukraine have been launched into space. With the low-cost threshold of small satellites, that number is expected to skyrocket. With that comes the question: Who will be in space in 10 years, and what will they be doing? Unfortunately, the answer is likely not all good. It’s not hard to imagine a terrorist organization working with a friendly nation to develop CubeSats with reconnaissance capability hitching a ride into LEO. With more access comes more opportunities — for allies and partners as well as adversaries.
Managing risk, fostering cooperation
A leading challenge is to develop faster and smarter than the rest. The U.S. and its allies and partners must acknowledge that many nations now have access to space, and it must become a strategic military priority to introduce resiliency and redundancy into space systems. In short, nations must spread the risk. The good news is that advances in distributed computing and machine learning mean scientists can create a distributed network that can heal itself. So, if one satellite out of a constellation of a hundred is damaged, the others can compensate for that disability.
Also, the technology must be optimized. If there are more small satellites gathering more data than ever before, the next question becomes: How will that data be processed? Then, of course, there are myriad other questions as well: How do nations secure their networks? How do nations make their satellites impervious to space weather (that is, any and all conditions and events on the sun, in the solar wind, in near-Earth space and in the upper atmosphere)? Los Alamos, for one, is leveraging decades of experience developing space instruments, understanding of the extreme space environment and supercomputing prowess to answer these questions.
It’s not only about developing the right technology, however. The U.S. and its allies and partners must also plan carefully — and not just on a national scale — but on a global one. Just as the international community has figured out international shipping and air traffic routes, the international community needs to collaborate to figure out how to work cooperatively to regulate space.
The reality is, during the next few decades, space will become more and more crowded and how it’s used will change the world. That change is coming quickly. Will the international community rise to meet these challenges before they overwhelm Earth’s orbits ? If the answer is to be yes, nations must start working together to solve these issues now.