A look into the past of the universe

Paris – Given billions of years in the universe – that should be possible with the new James Webb Space Telescope. After decades of development and many delays, the rocket carrying a precious payload is now scheduled to be launched from a spaceport at Kourou in French Guiana on Christmas Eve.

The new telescope far surpasses its predecessor, Hubble, in size and complexity. Its mirror is 6.5 meters in diameter and needs to be folded to fit the Ariane 5 rocket that will put the telescope into orbit. The James Webb Telescope will explore the early days of the universe, just a few hundred million years after the Big Bang. The US space agency “NASA” explains that it “will directly observe an unprecedented portion of space and time.”

Looking more into space means looking more into the past. While it takes sunlight eight minutes to reach our eyes on Earth, the new telescope will capture the light of the first galaxies that formed over 13.4 billion years ago.

Astrophysicist: Webb could reveal ‘many, many galaxies’

The Hubble satellite, which has been in use since 1990, mainly monitors visible light. On the other hand, Webb focuses on infrared. The telescope will provide more accurate images, with a sensitivity 100 times higher, says Swiss astrophysicist Pascal Auch. He is sure that “more and more galaxies will be revealed, but they are much less bright”.

Webb will help explain a key stage in the evolution of the universe, when “the lights came on when the first stars began to form,” explains Oesch. In the end, it is also about knowing whether the Earth is unique or whether there are similar planets on which life could originate.

The new telescope, named after a former US space agency administrator, was jointly developed by NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA). The Max Planck Institute for Astronomy, the University of Cologne and several German companies also participated in the conference.

Telescope mirror and sun shield the size of a tennis court

The project, which began in 1989, was originally supposed to start in the early 2000s. Ever new problems delayed the project, costs tripled to nearly $10 billion (€8.8 billion). “There’s a lot of excitement, we’ve been waiting for this moment for a long time,” says Pierre Verroet, a scientist at the European Space Agency who has devoted most of his career to the project. Researchers are already vying for access to the new telescope that orbits our sun.

“The demand for observing time is very high. In the first year of operation alone, the European Space Agency received more than a thousand requests,” says Ferrouette. “Even after 20 years, the questions Webb is designed to answer are just as urgent.”

But it will take some time before the telescope delivers the first images: in about a month it should reach its orbit 1.5 million kilometers from Earth. Then the mirror and sunscreen the size of a tennis court should open. Only when this challenge is mastered and the mirror is finely tuned can a look into the universe’s past begin in about half a year.