James Webb goes further into space

it is time. At the end of December, the most advanced space telescope ever was launched: the James Webb Space Telescope. This makes our view of the past, black holes and new exoplanets better, clearer, and more sensitive.

After more than 25 years of work, and many postponements and delays, the space scientist is eagerly looking forward to December 22nd. then go – fingers intertwined – It recently launched the James Webb Space Telescope from the European Space Agency’s base in French Guiana, which is always referred to as “Webb” by participants.

The device travels deeper into space, with greater sensitivity and resolution than its predecessors, such as Hubble. Webb does this by collecting light in the near and mid-infrared (see figure below). After the Big Bang, everything in the universe started moving away from each other and the further away you looked, the more everything turned red.

Best in every way

‘Web is better in many ways. It’s more sensitive thanks to its larger plate, so it looks deeper into the universe. But it also takes clearer images’, explains Professor of Molecular Astrophysics Ewen van Dyschwyk from Leiden University.

Van Dishoeck is one of the scientists who created Webb. In the late 1990s, we decided to start lobbying with some scientists in Europe and the United States to get an instrument at the observatory that could detect infrared radiation.

Dutch optics

This lobby has paid off and thanks to a collaboration with NASA, the space telescope is now equipped with the MIRI Measurement Instrument (MIRI).mid infrared instrument) on board. The United States built detectors and cooling devices and Europe built instruments, such as the camera and spectrometer. The optics of this are largely Dutch.

The entire space observatory is a collaboration between NASA, the European Space Agency and the Canadian Space Agency, and the space agencies of the United States, Europe and Canada respectively. Europe will provide two main instruments, MIRI and NIRspec, moreover, the European Space Agency will also provide the launch of the Ariane 5 rocket. The development of Webb cost an estimated $8.8 billion (€7.8 billion).

folding mirror

A few months ago, the 6.5-ton space telescope was flown from Los Angeles to Kourou in French Guiana. The work there continues 24 hours a day, 7 days a week. Fortunately, we are way ahead of schedule.” systems engineer Maurice T-Plate of the European Space Agency in mid-November, having just returned from French Guiana, where he completed his last major pre-launch tests.

folded in the nose of the missile

Almost everything is distinct from the web. “It is the largest and most complex observatory ever built,” T-plate said. “It’s just too big to fit in the front of the rocket. It has to run when folded. It’s never been done before.”

For this reason, Webb’s primary mirror is divided into eighteen hex segments that must eventually connect seamlessly. Together they form a mirror with a diameter of 6.6 meters; Hubble’s fixed mirror measures 2.4 metres.

Six to seven times the light

“This large mirror is one of Webb’s strengths,” T-plate says. Just as a large bucket catches more raindrops than a small cup, a large mirror captures more photons. Webb captures six to seven times more light than Hubble.

layer of gold

The individual mirrors are made of beryllium and covered with a thin layer of gold, which perfectly reflects infrared radiation. Under each mirror piece are seven mechanisms that can rotate in different directions. In the end it should be the whole mirror rock solid To be able to monitor properly. Every few weeks we check the wavefront quality of the light.

The incoming light falls on the primary mirror, then on the secondary mirror and from there it travels into the interior of the telescope, where the light is finally split off and directed to the various instruments. This way they can make notes at the same time.

Have you read more about the James Webb Space Telescope?

The full story can be read in the December issue of De Ingenieur. Buy the digital edition for 7.50 euros, or get – at a huge discount of 25% – a digital annual subscription of 12 issues for 69 euros.

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