Ewine van Dishoeck goes stargazing
From the birth of the universe to the molecules in a planet's atmosphere. The first five pictures from the James Webb Space Telescope (JWST) show the enormous range in which the space telescope can operate. Ewine van Dishoeck, professor of molecular astrophysics, took a look at the first images Tuesday at the Rijksmuseum Boerhaave.
After six months of cooling, testing and calibration, the new flagship for infrared astronomy started its official scientific duties at the end of June. Yesterday, the first images from the telescope were shown to the public. A packed lecture hall in Museum Boerhaave waited anxiously for the images that NASA released one by one. Ewine van Dishoeck led the countdown: 'What a special day today.’
A little Dutch flag in space
Van Dishoeck was closely involved in the development of one of the four instruments on board the JWST, the MIRI. The MIRI is a camera that can measure infrared light with long wavelengths. Van Dishoeck: 'The spectrometer that is part of the MIRI was designed and built by NOVA. We are very proud to have a small Dutch piece on board the JWST. And now we finally know that it works!’
About as sharp as Hubble
But do not expect sharper images from the JWST. Although the telescope is much larger than, for example, Hubble (6.5 metres versus 2 metres), it produces a completely different type of image. ‘Whereas we humans only see visible light, Webb looks at infrared light,' Van Dishoeck explaines. ‘Because the wavelength of infrared light is longer, we need a larger telescope. So, in the end, JWST's images are about as sharp as Hubble's.'
Making the invisible visible
Nevertheless, the new images from JWST are the best so far. Because we look with infrared eyes, we can do two things that Hubble cannot do: 'With infrared we can look through the large dust clouds in the universe and see what is behind or in these clouds. And we can see much further. Light that travels long distances to us shifts further and further towards the infrared spectrum and therefore becomes invisible to Hubble.’
An orchestrated show by NASA
The first five images from JWST clearly show what this looks like. One by one, they appear on the big screen in a live stream orchestrated by NASA. Van Dishoeck cannot restrain herself from standing up here and there to show where her MIRI is stealing the show. Afterwards, she runs through the images one by one.
For example, there is this picture of the Southern Ring Nebula. It shows two stars, one of which is at the end of its life. Therefore, it has been scattering material for thousands of years, creating the (beautiful) cloud around the stars. ‘Because we are looking in infrared, we can really see things that we wouldn't have seen otherwise,' says Van Dishoeck. For example, the second star that is inside the cloud is simply invisible to Hubble.
Or this one of an enormous dust cloud called the Carina Nebula, a place where stars are born. It has previously been beautifully portrayed by Hubble. But now, thanks to the JWST, we can look through the clouds of the nebula and peek right into the nursery of these stars.
The first articles are coming
Yet Van Dishoeck, who describes herself as a spectroscopist, is perhaps most excited by the image above. Using so-called spectroscopy, you can see what kind of molecules are found in space. ‘I am looking forward to the coming days and weeks,' says van Dishoeck, 'when we will see even more of these kinds of spectra. I like the earlier pictures because of their beauty. But the science I do is all about spectra like this. As soon as this data is made available, I expect the first scientific articles to be published very soon.