Space: A New Approach
BY BRAD WALLACE
© 2008 FrontLine Defence (Vol 5, No 6)

“Space promises too much, delivers too little, is too expensive, and always takes too long.” This comment typifies a common perception of space systems in the Canadian Forces – and not without justification. In a world where military satellites can cost a billion dollars, and where it can take 10 years to place 20-year-old technology in orbit, one can hardly criticize those who have grown skeptical about space. But space is changing.

Moving away from the 2000 kg, multi-hundred-million dollar behemoths like RADARSAT and the SPOT satellite (Satellite Pour l’Observation de la Terre), increasing computing capacities, greater miniaturization and decreased power requirements are making smaller, more capable spacecraft possible. Some of these technologies are allowing us to develop the capabilities that the Canadian Forces will need 10, 15, or 20 years out. Some are yielding capabilities that are ready today.

At the forefront of this “microspace” research are scientists from DRDC (Defence Research and Development Canada), the Canadian Space Agency (CSA), the Canadian Forces (CF) and Canadian industry and academia. What follows is an account of their work and the context in which they are operating.

An Eye on Space
Last year was a bad one for space debris. China tested an anti-satellite weapon, single-handedly increasing the amount of space junk being tracked by 25 percent. A Russian rocket that failed to reach its intended orbit exploded, placing an unknown amount of debris in orbit (unknown because everyone was busy dealing with the higher-priority anti-satellite test debris at the time). And a Russian spacecraft that had ended its usable lifetime exploded – twice! – increasing the amount of debris by five percent. This junk poses threats to spacecraft and astronauts that are in orbit, but who keeps track of this stuff? NORAD does, as part of its aerospace warning mission.
 
 
A computer-generated depiction of NEOSSat as it passes above Canada during its orbit.

The CF has historically played a role in the Surveillance of Space (SofS) through NORAD and, after an interruption in providing data, progress is under way to start contributing again. As it turns out, it has been demonstrated that one of the most efficient ways to keep tabs on spacecraft is with another spacecraft. As a result, the CF is placing the Sapphire satellite in orbit to do just that. But spacecraft have a limited life – what happens when it stops working?

Roughly a year before Sapphire is launched, DRDC and the CSA will be placing an experimental spacecraft in orbit that is designed to track space objects and which – as a bonus – will track asteroids on behalf of Canadian planetary scientists. This latter part of the story has garnered significant media interest as the world’s first space mission ever to search for asteroids, a minuscule 75-kilogram microsatellite costing a mere $10 million (including the price tag for launch).

Called the Near Earth Orbit Surveillance Satellite (NEOSSat), this spacecraft, being designed and built by Microsat Systems Canada Inc. (formerly the space division of Dynacon Inc.), is currently scheduled for launch in early 2010 after a development time of only about 3 years. After a one-year demonstration period – during which DRDC will work with the CF to evaluate the quality and usefulness of the data – the CF will be given the option to take over DRDC’s time on the spacecraft.

While the data that NEOSSat will provide will be useful in itself, perhaps the most important value will be the demonstration that microspace can be useful for the military. By showing that these inexpensive and focused spacecraft are able to meet a military need, NEOSSat will not simply be demonstrating a new technology, but will also be demonstrating a new way of doing business. Furthermore, future space systems will be able to take advantage of these advances.

An Eye on the Seas
If the idea of a satellite keeping an eye on other satellites seems a little circular and remote, perhaps a satellite keeping an eye on shipping seems more relevant. And that is what DRDC’s second microsatellite ­mission is going to do.

The CF has the responsibility to ­monitor and (if needed) police the three Canadian oceans out to 1000 nautical miles. This, it hardly need be said, is a challenge. And if monitoring such a large area is difficult, identifying and keeping track of the ships within the area is no easier. Enter AIS – the Automatic Identification System.

AIS is a beacon – mandated by the International Maritime Organization – which every ship larger than 300 tons has to carry. AIS is a cooperative safety-at-sea measure, letting ships within line of sight of the beacon know who is in the area, where they are, and what their bearing and speed are.

The intent of the measure is – at its most basic – to avoid possible ­collisions between ships, however, it turns out that this information is exactly what the Coast Guard and CF also want. And while there are AIS systems – using landbased, ship-borne, air-borne, and buoy-based radios – that do thorough work very close to the shore, there are not any that get even close to 1000 km. None.

So what about satellites? It turns out that a space-borne AIS receiver can actually detect signals from ships. Importantly, it can do so over a large swath of sea, allowing predictable monitoring of traffic within the Canadian areas of interest and enabling more efficient follow-up tasking. And best of all, it can do this from a microsatellite-sized platform.

This is exactly what DRDC is demonstrating – but not simply the space-based AIS detection capability, nor even the microsatellite platform. The most important component is demonstrating the operational worthiness of this data, which will be shared between the CF and its Canadian governmental partners. The satellite, to be called M3MSat (Maritime Monitoring and Messaging MicroSATellite), is being built by Comdev Ltd. out of Cambridge ON, and will have a similar mass (60kg) and cost ($10M) to NEOSSat. Learning from the latter’s development, DRDC has been able to shorten M3MSat’s development time by 6 months, further proving the operational potential of microspace solutions.

An Eye on the Future
Despite the allure of microspace – the focus, the low cost, the quick turn-around – there are some things that simply need size. Radar, for example, needs a large antenna area for sensitivity, and large solar panels for power, and these have associated costs. Often, though, there are advantages in not concentrating everything in a single satellite but instead across several smaller spacecraft that operate together. Many of the required technologies are still in the R&D stage though, and need to be tested in orbit.
 

A view of the group of nanosatellites attached to the payload section of the Indian PSLV rocket. CanX-2 is located underneath the longer release mechanism located at middle right, and a second SFL nanosatellite (CanX-6) is mounted at upper left.
 
The issue, of course, is cost. Getting money to demonstrate a technology in orbit is hard enough, but getting an equivalent amount of funding to simply test a technology is even harder. There is a solution that allows DRDC to move forward, however, and that is to go even smaller.
 

A view of the payload of the Indian PSLV rocket that placed CanX-2 on orbit. The main payload (top) is the Indian ­CartoSat-2A remote sensing satellite.

DRDC, along with the CSA, is helping foster Canadian capabilities in nanosatellites – spacecraft 20cm on a side, with mass less than 10 kg, and a cost dropping below a million dollars to design, build, launch, and operate. With funding and support from DRDC, CSA, and other sources, the Space Flight Lab (SFL) at the University of Toronto Institute for Aerospace Studies (UTIAS) is pushing the boundaries on the capabilities of these extremely small spacecraft, and at the same time providing a platform for developing the next generations of spacecraft.

One of the main technological challenges for increasing the utility of small spacecraft is to make them operate in tandem, and to have them do so with as much autonomy as possible. This is no small challenge. Formation flying, as it is called, requires that spacecraft know where they are precisely, know where the companion spacecraft are located, and be able to manoeuvre, again precisely, to keep configurations stable in the face of perturbing forces like magnetic fields, solar pressure, Earth’s tides, and atmospheric drag.

To develop these technologies, UTIAS SFL is working to place twin nanosatellites – to be called CanX-4 and CanX-5 – in orbit to autonomously manoeuvre around each other in desired ways, a mission that requires significant technological development and research. As a prelude to this dual spacecraft mission, SFL has – just this April – placed a nanosatellite 3.5 kg in mass in orbit to test novel propulsion, precision manoeuvring and precision attitude control systems. This mission – dubbed CanX-2 – was launched on board an Indian rocket as part of a mission that placed a total of 10 individual satellites in orbit – a world’s record.

Wrap Up
So what is the takeaway? DRDC is fostering Canadian capabilities that are making space smaller, more nimble, and more affordable. Realizing the full benefits of these capabilities requires new ways of operating a potentially large number of small systems, and DRDC is developing technologies to allow these spacecraft and associated ground systems to operate as autonomously as possible. The fruition of these efforts will directly benefit the CF by giving it options for new ways to perform its military missions, and to create unique capabilities suited to its unique needs.

The key to the change is focus. If space advocates promise too much, the solution is to focus instead on a single customer and a single mission that yields a smaller spacecraft, one less expensive to build and (in a world where launch costs are $10-50K per kilogram) less expensive to put in orbit. Ultimately, the compressed development timeline will also reduce the labour costs associated with having a “marching army.”

In this way, DRDC is addressing all the issues raised at the top of this story. By keeping promises achievable, costs affordable, and timelines short, DRDC expects the microspace sector to grow its operational capabilities very quickly.
 
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Brad Wallace holds a Ph.D. in Astrophysics from the University of Calgary. He has worked for the National Research Council’s Herzberg Institute of Astrophysics in Penticton B.C., and for the U.S. Smithsonian Astrophysical Observatory at the Sub-Millimeter Array in Hawaii. Dr. Wallace joined DRDC in 2000 and currently leads the Surveillance of Space R&D efforts there.
© Frontline Defence 2008

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