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REINDEER grazing in the Hardangervidda National Park in southern Norway will soon have their own shiny new satellite. As they roam among the frozen lakes and snow-capped mountains of the park, transmitters attached to the animals will radio their location up to a cube-shaped satellite about the size of radio-alarm clock. The craft will beam their coordinates to ground stations at Narvik in the north of Norway, and the remote Svalbard archipelago in the Arctic Ocean.

The experiment was initiated at the request of the International Maritime Organization, to help test a recently introduced high-frequency ship-tracking standard, called the Automatic Identification System. Using AIS, vessels broadcast their position, course and speed to other vessels in the vicinity. The test will demonstrate that the signal, normally transmitted between ships, can be relayed via satellite to extend its range.

What is most remarkable is that the “nano-satellite” monitoring the reindeer, called NCUBE2, was developed not by a space agency or multinational company but as an educational exercise by a bunch of students at Narvik University College. It was made possible by using a standardised satellite format called CubeSat, which dramatically reduces launch costs compared to traditional, bespoke spacecraft.

In sharp contrast to space tourism, which is likely to remain the preserve of the astronomically wealthy for some time to come, CubeSat is intended to make space technology accessible and affordable. The miniature satellites are making what was once an exclusive playground for those with billion-dollar-budgets available to anyone with a modest research budget and a passion for space.

NCUBE2 will be carried into space tucked inside a larger European Space Agency (ESA) satellite called SSETI Express – Student Space Exploration and Technology Initiative. SSETI is expected to launch within the next couple of months, carrying not only its own scientific payload and NCUBE2 but also two more CubeSats: a German-built communications satellite and an Earth-imaging craft, XI-V, from the University of Tokyo in Japan.

CubeSats were the brainchild of Robert Twiggs at Stanford University in California. The body of each satellite is a cube 10 centimetres to a side and with a mass of no more than 1 kilogram. This provides enough space for a computer, a communications system and a few instruments or other components of the designers’ choosing. All six faces of the cube can be covered with solar panels to provide very limited electrical power.

Researchers at California Polytechnic State University in San Luis Obispo (Cal Poly) devised a simple, spring-loaded system called the Poly Picosatellite Orbital Deployer, or P-POD, for releasing several CubeSats from a launcher simultaneously. By packing several CubeSats onto the same rocket, Cal Poly can launch a satellite from Russia for a flat fee of just $40,000 per shot. That’s far less than the $500,000 per kilogram typical for a commercial satellite launch.

The first CubeSats were launched in June 2003 from the Plesetsk Cosmodrome in the far north-west of Russia, and more launches are scheduled for this year. During 2006 a total of 21 satellites are expected to blast off, marking the start of a major push in the CubeSat programme. More than 60 groups of researchers around the world are working on their own CubeSats.

“It’s definitely gaining momentum, especially in countries that don’t have a big national space programme,” says Armen Toorian, CubeSat programme manager at Cal Poly. An emerging online CubeSat community is helping students and researchers share their experiences and design ideas. Twiggs likens this free exchange of expertise to the way the free software movement encourages programmers to build on each others’ ideas.

Many CubeSat teams are able to keep costs down by using off-the-shelf components to build their craft. For example, the Japanese team behind X-VI will use a standard digital camera to capture still pictures of the Earth from orbit. The pictures will not match the quality of those produced by commercial imaging satellites, but the lower cost makes up for that.

Such Earth-monitoring CubeSats could be launched in response to natural disasters, according to Wayne Shiroma at University of Hawaii, who is investigating this use for the satellites. “Ground-based sensing and communication systems are unfeasible in the aftermath of a natural disaster, as they are often compromised.” A more attractive solution, he says, is a CubeSat surveillance and tracking network that is flexible, dynamically reconfigurable, and readily deployable.

“We started our CubeSat programme as something fun for students to do, but it has evolved into a bona fide research endeavour,” he says.

Because every CubeSat is intended for a different application, each presents its own design and manufacturing challenges. “There is real science in designing and building these satellites, using novel miniaturised designs, extremely low power and limited weight,” says Tommy Gravdahl of the Norwegian University of Science and Technology in Trondheim, who helped develop NCUBE2.

One promising application for the satellites is as a testbed for experimental hardware. For example, a CubeSat developed at Cal Poly and launched in November 2004 tested a prototype sensor for detecting the sun’s position in the sky. It was developed by Connecticut-based company Optical Energy Technologies, for systems that orient solar panels towards the sun. “You can test components quickly and easily by throwing these satellites up,” says Max Meerman, an engineer at Surrey Satellites, UK.

CubeSats do not have their own propulsion systems, so once launched they cannot be moved to a different orbit. But Meerman thinks this could change as more sophisticated components become available. “Perhaps in a few years you’ll be able to do propulsion and control as well.”

Another application for CubeSats is as a vehicle for scientific experiments that can only be done in space. GeneSat-1, built by NASA and a consortium of universities led by researchers at San Jose State University in California, is scheduled to launch this year to assess the damage space radiation can do to genes. The satellite contains an automated miniature laboratory that will detect changes to the DNA of E. coli bacteria by attaching florescent markers to cells that will show up under light from blue LEDs. A microscope will record any changes and the craft will transmit the results back to Earth. GeneSat-1 is bigger than a standard CubeSat: it will be the shape of three CubeSats fixed together in a configuration that will allow it to use Cal Poly’s P-POD deployment system. A trio of CubeSats will also form part of a project to test an experimental space tether (see “Tether test”).

Twiggs, meanwhile, has turned his attention to even simpler satellites, and has developed a version of CubeSat that can be built and modified by high-school students. He would like to see this kind of cheap, accessible satellite available to all. “When the average person can put a satellite into space, the interesting thing will be seeing what they’ll do with it,” he says.