Satellites have come a long way from their origins in the 1950s. Much like the phone in your pocket, they’re a lot smaller, cheaper, and faster to build than their forebears.
Today’s game-changing designs are known as ‘nanosatellites’, and Australia has a growing reputation for developing them. The University of Melbourne is helping to lead the charge with its Space Industry Responsive Intelligent Thermal (SpiRIT) spacecraft.
A compact powerhouse
SpIRIT is a CubeSat, a type of nanosatellite built using 10cm cube units. Six of these units feature in the SpIRIT design, making it roughly the size of a shoebox and just 11.5kg in weight.
That small form factor is packed with cutting-edge Australian technology. SpIRIT will fly with:
- cameras
- guidance systems
- communications antennae
- artificial intelligence computers
- a miniature electric propulsion system.
Many of these features will operate in orbit for the first time. Project leader Professor Michele Trenti is eager to prove they can function on such a small spacecraft.
“SpIRIT is an ambitious satellite for its class of weight,” Professor Trenti says.
“One unique element is a powerful thermal control system with a Stirling-cycle cryocooler and deployable radiators, that will demonstrate in-orbit the ability to lower and precisely hold the temperature of advanced instrumentation.”
“This technology is expected to open the opportunity for nanosatellites to fly remote sensing instruments that so far have been restricted to spacecraft ten times heavier, and more expensive.”
To develop the satellite, the University of Melbourne led an all-Australian consortium that includes:
- Inovor Technologies
- Neumann Space
- Nova Systems
- Sitael Australia.
In December 2022, the University of Melbourne also signed a Memorandum of Understanding with Leonardo Australia to commercialise SpIRIT’s thermal management technology.
Hunting gamma rays
Alongside the local technology, SpIRIT will become the first Australian satellite to carry a foreign agency payload: the Italian Space Agency’s HERMES (High Energy Rapid Modular Ensemble of Satellites – Scientific Pathfinder).
HERMES is an advanced X-ray detector that can localise high-energy gamma ray bursts in space. These are significant explosions that can occur when stars collide or die and become black holes.
“This a capability that has so far been restricted to heavier and more expensive satellites,” Professor Trenti says.
“The HERMES instrument will also have a world-leading ability to time-stamp the arrival times of photons and their energy. This will enable novel studies into the nature of quantum gravity, by looking at whether the travel time of photons depends on their energy.”
Just the beginning
SpIRIT will launch in late 2023 with ISISPACE on SpaceX’s Transporter-9. It will fly in low Earth orbit for 2 years, demonstrating the performance and endurance of the Australian-made technology on board.
Professor Trenti is excited to see the flight open the door to future commercial opportunities and help push the Australian industry forward.
“Many of the technologies that will be proven on SpIRIT will have strong potential to be adopted as part of future constellations. Thus giving a large return on the initial R&D investment,” Professor Trenti says.
“A project like SpIRIT, underpinned by the drive to carry out innovative science, challenges and stimulates the Australian industry to innovate and develop new products in collaboration with universities and research institutions.