The Industrial Sciences Group (ISG), a company formed from research centres at the Australian Research Council and the University of NSW, is one of ten successful grant recipients from the Australian Space Agency’s International Space Investment initiative.
The firm will develop a new tool to help satellite operators assess the risks to satellites from collisions with space debris. Currently, there are more than 20,000 satellites and pieces of debris tracked in orbit around the Earth.
The company is developing a new decision support system to enable satellite operators to make decisions with greater certainty and speed.
Space junk in Low Earth Orbit
‘Space junk’ consists of debris from previous space missions and whole satellites that are no longer operational. Current tracking techniques can monitor space junk down to a size of 10cm in diameter. These passive pieces of debris travel in different orbital altitudes at speeds of up to 28,000 kilometres per hour.
Debris is not controlled or manoeuvred. Collisions between space junk and satellites are a major concern in the space community, especially in Low Earth Orbit (LEO). There are more than 2,200 active satellites in LEO. These can move to avoid a collision, but this costs fuel, time and effort. Operators only move a satellite if the probability of space debris collision is high.
The Managing Director of Industrial Sciences Group explained that collisions have a low probability of occurrence but are a high risk in space. The team will need to actively manage the ‘traffic’ on the ‘roads’ in space, but there is no highway police up there. Even if something as small as a screw flies into a satellite, it can break the satellite apart and create more junk and debris.
The science of collision avoidance
Currently, possible space collisions are predicted ahead of time. But there is a lot of uncertainty when determining if a collision will occur. Industrial Sciences Group is tackling the problem with specialist expertise in statistics, mathematics, and astrodynamics.
There is no global approach to assess the risk and probability of a collision occurring in space, but the team aims to add some science and rigour to the decision-making process.
The NASA Robotic Conjunction Assessment Risk Analysis (CARA) is responsible for protecting all NASA satellites from catastrophic collisions. CARA has developed a concept for a Decision Support System (DSS) to assist satellite operators make collision avoidance decisions in real-time.
Industrial Sciences Group will develop the concept into an operational tool. They will use advanced maths and statistics to analyse CARA’s data on previous collision warnings to develop a rigorous approach for assessing and acting on the risk of collision. This new software has the potential to be a major contributor to space traffic management. The final outcome will be a decision support tool for satellite operators.
Australia working to further space exploration
Recently, it was reported that a local start-up an aerospace company in Adelaide, began its test program with two sub-orbital rockets on 14 September 2020.
The launch was a significant moment for Australia’s space industry – the next chapter in a history of rocket launches extending over six decades. The launch took place near the Indigenous community of Koonibba, an approximately 8-hours’ drive from Adelaide.
Launching northwards, each rocket was a Netherlands-designed 2-stage DART about 3.4 metres long and weighing 34 kilograms. In just 6 seconds of rocket burn, they screamed to speeds of Mach 5. The test rockets were not to reach orbit, however, and peaked around 85km above Earth.
They carried a miniature probe designed and built by an Australian electronic warfare engineering company. After reaching apogee, DEWC-SP1, as the payload has been dubbed, descended to Earth under a parachute. As it came down, the package of antennas and sensors performed a sensing mission, as well as being a test of withstanding the 50g of force during launch. Once landed, the payload was collected by DEWC Systems crew escorted by a local Aboriginal cultural monitor.
