"Smile" satellite soon to take off with Swiss technology

For the researchers involved, the launch is a special moment - and nerve-wracking at the same time. "I would love to go down to the basement at the launch and wait until it's all over," said André Csillaghy from the FHNW in an interview with the Keystone-SDA news agency.

Under his leadership, a Swiss consortium developed software for the mission as well as a crucial component of the hardware without which the telescope would not work. "A launch like this is a great moment - but your thoughts go to these very delicate parts that you have developed and built yourself and that are then on the rocket while everything is vibrating."

Csillaghy and his team from the University of Applied Sciences Northwestern Switzerland (FHNW), the Zurich University of Applied Sciences (ZHAW) and the Swiss companies KOEGL Space and Space Acoustics began working on the mission eight years ago.

Understanding space weather

"Smile" ("Solar wind Magnetosphere Ionosphere Link Explorer") is a project of the European and Chinese space organizations. The aim of the mission is to better understand - and perhaps even predict - space weather.

The weather in space is determined by solar winds and solar storms, in which charged particles are hurled out of the sun. The particles are hurled towards the earth at speeds of up to 2 million kilometers per hour. There they encounter an invisible protective shield: the magnetosphere. It deflects the particles.

However, when the particles hit the Earth's magnetic field, they not only cause auroras, but also complex interactions: Satellites can be damaged, navigation systems disrupted and even power grids on Earth can be affected. Smile" aims to comprehensively measure these processes.

The satellite is equipped with four scientific instruments for this purpose: an X-ray camera, an ultraviolet camera, an ion spectrometer and a magnetometer. While the UV camera can observe auroras for up to 45 hours at a time, the X-ray camera - known as the "Soft X-ray Imager (SXI)" - is the largest of the four instruments and will visualize the Earth's otherwise invisible magnetic field for the first time.

Rocket science from Switzerland

Switzerland made a decisive contribution to this X-ray camera: the cooling system for the telescope was developed, manufactured and tested at the FHNW in Windisch. The "radiator assembly", as the cooling system is called, is a kind of radiator, explained Csillaghy. "But a Rocket Science radiator."

The Rocket Science radiator is responsible for bringing the detectors to the required operating temperatures of around minus 110 degrees Celsius. The inconspicuous, rectangular panel measures around 30 by 40 centimetres and is mounted on the side of the telescope facing away from the sun.

"Without this cooling, the camera would not work," emphasizes Csillaghy. The extreme conditions in space - it can be up to 160 degrees on the sunny side and up to minus 200 degrees on the shady side - make the development of the radiator particularly challenging.

Swiss researchers also contributed software for the mission. They developed algorithms to improve the image quality of the wide-angle camera. The camera is designed to capture a huge region of the magnetosphere and is located comparatively close to the observed area. The particularly wide angle of view required for this makes it difficult to obtain consistently sharp and detailed images.

"Traditional methods are somewhat limited here," says Csillaghy. The team therefore relies on artificial intelligence and deep learning methods to make the relevant structures visible. As soon as the instrument is switched on, the researchers at the FHNW School of Computer Science are responsible for evaluating the data.