This is our time: Eleonie van Schreven’s work on small satellites with a big impact

Eleonie van Schreven works as a Systems Engineer on space projects at TNO. Her main focus at the moment is the TANGO satellite mission. This is an innovative, highly compact twin-satellite system for the monitoring of greenhouse gas emissions. TANGO is being developed specifically to detect sources of two greenhouse gases: methane and CO2. The satellite mission is a partnership with the Royal Netherlands Meteorological Institute (KNMI), the Netherlands Institute for Space Research (SRON), and satellite platform manufacturer ISISpace. TNO plays a key role in developing the technology.

Small satellite with astonishing accuracy

The European Space Agency (ESA) was looking for innovative ideas to develop small satellites for Earth observations. Last year, it gave the go-ahead for the Dutch TANGO satellites. Eleonie: ‘There have been plenty of experiments involving compact satellites in recent years, including by universities. TANGO is a unique opportunity to show how these can be used to generate complex scientific data, such as data on emissions.’

Soon, TANGO will be able to measure greenhouse gases in the atmosphere. It is a twin satellite mission, consisting of 2 small satellites flying together in formation. One satellite (TANGO Carbon) measures CO2 and methane, while the other (TANGO Nitron) measures nitrogen oxides. Each satellite is equipped with an instrument, which is composed of a telescope, a spectrometer and a detector. The telescope’s mirrors capture sunlight that has been reflected off the Earth and therefore travelled through the atmosphere twice. This light is broken down into different wavelengths, or colours, using spectroscopy.

Eleonie: ‘We can tell from the light's colours which gases it has come into contact with. For example, we know that CO2 absorbs certain colours. The more of those colours are missing, the more CO2 is present in the atmosphere. This allows us to measure greenhouse gases accurately.’

As big as two shoeboxes

Both satellites are about the size of two shoeboxes, measuring 40 x 20 x 20 cm. Eleonie: ‘To make the instruments fit inside, we had to reduce, or miniaturise, the technology. Each instrument measures a single wavelength region, or one to two gases. Existing instruments usually measure several different gases, but they tend to be very large and heavy and you would need to have a special satellite platform developed for that. Our instruments weigh less than 9 kg and can therefore be mounted on a standard platform. This saves a lot on time and costs.’

Another special aspect of the TANGO instruments is that they can measure with huge precision and with high spatial resolution. This means that they can zoom in on an area measuring 300 by 300 metres. Eleonie: ‘This will also allow us to detect smaller sources of greenhouse gases. This is going to make a huge contribution to the fight against climate change.’

From design to launch in just 3 years

Miniaturising technology calls for a vast amount of knowledge and expertise. All parts need to be made extremely precisely and work together seamlessly. Eleonie: 'My job is to ensure that all disciplines – such as optical design, mechanical design, and thermal design – come together nicely. This requires organisational skills as well as technical understanding. I’m not a specialist myself, but I talk to experts all day long, so I need to understand the technical side in detail.'

TANGO is a rather unique project for her. ‘Normally, space projects easily take 10 to 15 years, and you only work on a small part. However, because TANGO can be made much faster, we’re completing the cycle from design and build to testing and launch in just 3 years. We’re currently working on the design, which we’ll be testing in 2 years’ time. A year after that, the satellite will already be flying through space. It’s a lot of fun to be a part of all that.’

Top-quality instruments

It’s partly thanks to TNO’s knowledge and experience that it was possible to develop the satellites so quickly. Eleonie: ‘TNO has over 60 years of experience in space technology, and it shows. We have all kinds of disciplines in-house and are able to test and calibrate instruments ourselves. For example, if our calibration technicians have any questions, they can simply head upstairs and speak to our designers. Equally, I can go and ask the calibration specialists to take a look at something during the design phase. That way, you avoid problems further down the line.’

All of this results in top-quality instruments. ‘We’ve supplied an array of satellite components to clients in recent years, including advanced telescopes. Our clients consistently tell us how happy they are and that the quality exceeds their expectations. That’s always amazing to hear.’

Growing and making an impact at TNO

Eleonie has now been working at TNO for 5 years. She started in quality control before progressing to her current role. ‘I think that’s one of the best things about working at TNO: the fact that you can always grow. You’re constantly being asked: how are you doing? Are you still in the right position? And if you speak up and say that you want to grow, they’ll help you work out the best way to do that. They’ll ask: what do you need? Do you have any training in mind?’

What also appeals to her is TNO’s positioning: ‘TNO sits right at the intersection of science and industry. On the one hand, there’s an awful lot of knowledge and experience here, and you’re really working with cutting-edge technology. That means you learn a lot and you’re never stuck doing the same thing. On the other hand, it’s not all about the theory. We create functional products that are actually used in practice. Something else that I feel is important is that we work on issues that affect society. I’ve always wanted to do something to tackle climate change, and at TNO, I can.’

Range of new opportunities

What does Eleonie see as the next steps? ‘The TANGO mission just goes to show that small satellites can play a seriously big part in Earth observation and that we can develop them quickly and cost-effectively. This is a unique project that offers a range of new opportunities to tackle climate change. It’s fantastic that we are able to contribute to this.’

Carbyon

Curious about what else TNO is doing to combat climate change? Read about Carbyon, a start-up that focuses on CO2 filtering with the help of TNO.