Young Greek Australian Dr Steven Tsitas, a researcher at UNSW, has long recognised the need for Australia to explore ways to take space research to new frontiers and has developed a breakthrough technology that may well pave the way for an Australian space programme. His research, began at Cranfield University in the United Kingdom and continued in his spare time involves small satellites known as CubeSats.
With the smallest the size of a grapefruit, CubeSats are a standard developed in the United States initially for education purposes and according to Tsitas, are relatively cheap for spacecraft. Proving the popular adage that from little things big things grow, his peer reviewed and published research indicates that a spacecraft known as a 6U CubeSat, about the size of a typical shoebox and weighing just eight kilograms, can perform some of the missions of much larger ‘microsatellites’ weighing around 100 kilograms, or roughly the size of a washing machine.
According to Tsitas, this 10-times size reduction potentially makes the cost of producing a spacecraft 10-times cheaper amounting to a cost of around $1 million compared to $10 million. CubeSats sit in a ‘P-POD’ that looks like a rectangular mailbox, and is attached to the launch adapter connecting a much bigger spacecraft to the rocket launching it. Once in space, the P-POD is spring loaded to expel the CubeSats into space. “The launch adapter is where the CubeSat is attached.
The P-POD approach creates launch opportunities for very small satellites and is one of the things I admire about the CubeSat standard which was created in the United States,” Tsitas explains. “Three of the smallest CubeSats can fit inside a P-POD and once in orbit they are basically sprung out. The little ones are mainly for education but the reduction in size and cost makes larger CubeSats attractive for commercial and scientific missions.” Doubling the size of a 3U CubeSat – which is the size of three of the smallest CubeSats end to end – to 6U being the size of two 3U CubeSats side-by-side says Tsitas, leads to a marked increase in the technology’s capabilities, while still benefiting from the low cost of CubeSats.
The cost he says may now be low enough to make it politically possible for Australia to have a sustainable space program based on this spacecraft. “Given this new found capability and its modest cost, it is a good opportunity for Australia to use it as a basis for getting a foot into the space industry, designing and building our own spacecraft,” Tsitas says. Many would be surprised to learn that even though Australia was the fourth nation to build and launch a satellite from its own territory, it remains, even now, almost completely reliant on satellites owned and operated by other countries. “We currently don’t have anything like the United States in the sense of designing and building space craft.
We do have some space related activities, but nothing compared to the work and research going on in many other countries. We have no space agency for example, however most countries do see the wisdom in fostering a space program, including countries less wealthy than ours,” Tsitas explains. This may primarily reflect the government’s belief that in light of the significant costs associated with space activities, international collaboration enables Australia to share this cost. As Dr Tsitas explains Australia should not rely on other nations’ space programs forever and the time has come to invest in new scientific frontiers.
He says the need for a national space program is not just about pure research, nor just about economics, but just as importantly about strengthening collaborative opportunities between Australia’s great research agencies and other stakeholders including the creative manufacturing, aerospace, electronics and software industries. “The space industry is an extremely value-added industry, for example spacecraft is literally worth more than it’s weight in gold. Not only is it a high value-added industry it also has a high growth rate and this would suggest that it is a good industry to be in.” Due to the phenomenal costs involved, the spacecraft market is a very difficult one to enter.
However Tsitas believes the time is right for Australia to build instruments suited to the nation’s specific needs and take the first giant steps towards Australian-built satellites and spacecraft. This last remaining niche of 8 to 40 kilogram spacecraft he believes provides the best opportunity for Australia to have a sustainable space program. Starting with 6U CubeSats, the technology could be used in the fields of astronomy, atmospheric science and other planetary science, space physics, earth observation and biology to name a few. “The satellite could be used for agricultural monitoring. It could observe in medium resolution in five colours including two near infrared colours.”
It is often a repeated argument that money dedicated to the space race could be better spent on more worthy causes like health care and education. However such an argument ignores the fundamental reasons behind space exploration, reasons that transcend issues of national budgets. We are now in a time when we are set to discover things that were once unknown, perhaps fundamentally changing our understanding of Earth, science and even ourselves. The benefits are real and worth paying for, as it is really all about our long term future.
“People in the past have always said how and why can we be doing things in space when there are people starving? The fact is, how can we not, because agricultural monitoring by spacecraft can help improve food security. ” His interest he explains is using this design and for around a tenth of the price, producing these and selling them to developing countries. “In this way every country can afford to have its own satellite up in orbit, creating a constellation of satellites. Then every time the orbit of any satellite goes over the country they can image their crops which may help improve agricultural productivity.
The Global Financial Crisis may lead people to overlook the food crisis, but food security is still a concern. The satellites would be designed to de-orbit within 25 years, satisfying international standards for orbital debris mitigation.” While Australian space engineers are mostly working overseas, the message that Dr Tsitas wants to get out there is that low cost small spacecraft technology can be explored and exploited right here in Australia. “One of the advantages of such small and relatively cheap spacecraft is that the use of advanced technologies can be risked, because a failure need not be financially crippling as it may be with a larger, more expensive spacecraft.
This endows the smaller spacecraft with enough of the capabilities of the larger more expensive spacecraft to make it capable of carrying out some of the missions of larger spacecraft.” As there are apparently no commercial players using the 6U CubeSat it certainly would seem a way for Australia to take the lead. “I think that when Australia does decide to do something it usually does it world class and that is a step we should be taking in spacecraft designs and manufacturing,” Tsitas says.
As well as providing economic opportunities for Australia, utilising this technology would seemingly improve our strategic relationship with the United States and perhaps more importantly inspire the next generation of students to study science, technology, engineering, and mathematics. Scientists are fascinating people. While many people’s careers are based on getting ahead, even at the expense of others, scientists’ goals are often not so much personal as collective, dedicated to the betterment of humankind.
So what drives someone to become a scientist in the first place? “As a kid I always loved space and was curious about how the world works, reading books that explained the natural world and playing around with an electronics kit, chemistry set and small telescope. I went to Melbourne High School which was where I became a good student. I remember going to a school assembly at the beginning of my year 11 and the invited speaker gave a speech that inspired me to really apply myself to my studies and I did pretty well from then on.”
He went on to earn a PhD in Planetary Science from the California Institute of Technology, the Caltech referred to on The Big Bang Theory. Tsitas subsequently obtained a masters degree from Cranfield University in the United Kingdom. Curiosity may have killed the cat but not so scientists who are like dwarves standing on the shoulders of giants. This metaphor, famously used by Isaac Newton describes how humans driven by curiosity, build on what has come before. Space exploration like any form of science is about knowledge, about expanding our horizons and answering questions that we haven’t even thought of asking yet.
“I’m interested in not just asking why something works the way it does, but how to use it for potential benefit.” Dr Tsitas currently works as a senior research associate at UNSW on a project funded by the Australian Space Research Program. Tsitas is employed in a design study for a synthetic aperture radar satellite for earth observation.
He explains a synthetic aperture radar can determine where each echo from the ground comes from, like a chess board location with co-ordinates. This information allows scientists to create a picture of the earth using radar and is a powerful tool for imaging the earth, which has relevance for Australia. “You can see through clouds and at night are sensitive to the amount of moisture in the soil. Imaging the earth is important for us. For Australia I found that mapping soil moisture levels in the Murray Darling Basin using synthetic aperture radar may be an important application for improving water management there.
“I also have an idea for monitoring bush fires from air or space through cloud, using two synthetic aperture radar images taken a short time apart from about the same location. Synthetic aperture radar can create photo-like images but it also measures something called phase which is basically the exact distance to each point in the image. Changing the vegetation by burning it may change the phase enough to detect this….optical images can’t measure the phase and can’t see through cloud. It’s a theory I am keen to see tested.” Such projects have the potential to contribute to a truly global humanity. If Australia wants to be a part of that then perhaps it really is time to take some giant steps.
Anything less will see us left behind. People like Steven Tsitas are the source of such progress. They are creating tomorrow today. But their efforts can only succeed in a culture that truly values science and technology. It is to be hoped that Tsitas’ work in potentially launching an Australian space program will be rewarded.