Space Telescope James Webb, successor to Hubble, arrives at workplace | Abroad

While the new telescope zooms through space on Monday, flight control on Earth wants to switch on the engines around 8 p.m. Dutch time. This should change the course of the probe. In this way it can be ‘parked’ in a stable place in the shadow of the earth. It uses as little energy as possible there, has an unobstructed view of the universe and can easily send images and measurements.

The James Webb is the successor to the famous Hubble Space Telescope. It dates from 1990 and has been in orbit around the Earth for almost 32 years. His end is near. That is why Europe, the United States and Canada have joined forces for the new probe. From the Netherlands, Leiden University and research institute TNO are involved in the project, among others.

The new space telescope is about the size of a tennis court. The core is a 6.5-meter mirror, six times the size of the Hubble. That mirror was flipped open two weeks ago. It captures the light from space and reflects it to a second mirror, which bundles the light and sends it to the measuring instruments on board. The main mirror consists of eighteen hexagons that sit together, but can move independently of each other to focus. The mirror is made of beryllium, with a tiny layer of gold 100 nanometers thick on top. That’s a thousand times thinner than a human hair or a sheet of paper. Beryllium is light, strong and can withstand extreme cold. Gold makes the mirror better able to see infrared light.

Among other things, the James Webb has to search for planets where life might be possible, distant galaxies and traces of the Big Bang. It can see a billion years further back in time than Hubble. Because the James Webb is so far away, it is not bothered by the heat of the sun. At his workplace, the temperature is 233 degrees below zero. This makes the measurements more accurate and reliable. The project will cost a total of approximately 8 billion euros.

When the James Webb is at its final destination, it can’t get started right away. One of the measuring instruments on board must be cooled to 266 degrees below zero. That takes about a month. After that, it takes a few months to test if everything is working properly. The James Webb will probably be able to take the first measurements in the summer.

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