Leiden University: Mapping the universe with a NWO grant of 3.1 million
With the new Euclid satellite, scientists are going to map a large part of the sky. The satellite ofthe European Space Agency (ESA) will soon give them a better view of the galaxies and matter in the universe. Professor of Galactic Astronomy Koen Kuijken and a team of Dutch scientists are receiving a NWO grant of € 3.1 million to analyse the results of the satellite. This will bring them one step closer to understanding the mysteries of the universe.
After its launch, the satellite will take pictures with a wide-angle camera for six years. ‘Each image that Euclid takes, is one and a half times the size of the moon,’ says Kuijken. ‘And we are going to do that at least 30,000 times. When we then combine all these images, we will have mapped a very large part of the universe.’
Most detailed map of the universe ever made
This will be the most detailed map of the universe ever made. ‘Because it scans the sky with both optical light and infrared, we can see an enormous amount of detail. The three-dimensional map will also show the distribution of galaxies and matter in the universe. From that, we can get a lot of physical laws on how the universe evolved, how it is put together and what its ingredients are.’
More knowledge about dark matter and dark energy
The scientists also hope that the project will shine a new light on dark matter and dark energy. ‘Together they cover more than 95% of the universe. Yet we still know very little about their physical characteristics, how they behave and whether they are constant or evolve over time. We hope to learn more about these essential questions in physics and really understand their ingredients. Because if they weren’t there, we wouldn’t be there either.’
Infrastructure to handle billions of pixels
At least two thousand people are involved in the European project. Kuijken and the Dutch consortium of around ten experts are engaged in the scientific analysis of the data. ‘We didn’t work on the construction of the satellite, but we did contribute to the infrastructure on the ground. Because Euclid will give us so much data, that infrastructure is needed to process the billions of pixels. I like that better than being involved in the engineering of the satellite, because here you are much closer to the data.’
The NWO grant that Kuijken and the team receive will go entirely to the scientific analysis. ‘Together with a team of scientists who master various aspects of physics, as well as people who have knowledge of the evolution of galaxies, we will analyse the data. Thanks to the NWO grant we can employ eleven PhD students and postdocs to contribute to this.’
No James Webb 2.0
In December 2021, the James Webb telescope also went into space. A few months later, it sent out its first beautiful images. Yet, the Euclid is a completely different kind of instrument. ‘We’re in an incredibly luxurious position in terms of astronomy right now. We’ve been given so many new toys, that’s really fantastic,’ Kuijken says while laughing. ‘James Webb is designed to be able to look very deeply into small patches of sky. Euclid does the opposite: it looks very wide, but it is also sharp.’
Looking for a rocket
It is not yet clear when exactly the satellite will go into space. Kuijken hopes for the end of next year. ‘We were supposed to launch Euclid in the spring of next year on a rocket from the Russian space agency. One day after the invasion of Ukraine, this collaboration was terminated. We are now looking for another rocket. It might be one from ESA or an American one.’
‘Also just beautiful images’
Kuijken is certainly looking forward to receive the first data from the satellite. ‘I have been researching dark matter in many different ways throughout my career. The last ten years, I’ve mainly been involved in the ‘KiDS’ project that uses data from a telescope in Chile. That provided us with a lot of interesting insights, but Euclid is the ultimate experiment: going into space and collecting the best kind of data you can get.’
And that is not all. ‘I’m incredibly passionate about the night sky. And this is going to provide the most beautiful images on the most gigantic scale we’ve ever had and will have in the next 20 years. It’s also simply aesthetic. I get a lot of pleasure out of looking at those images and discovering new things in them.’