The world’s largest and most powerful space telescope has reached its final destination – an observation post one million miles away from Earth.
Nasa’s $10bn James Webb space telescope launched on Christmas Day last year from French Guiana on a quest to behold the dawn of the universe. Due to its sheer size, Webb had to launch folded inside the Ariane 5, a European rocket.
The mirrors on the space observatory must still be meticulously aligned and the infrared detectors sufficiently chilled before science observations can begin in June. But flight controllers in Baltimore were euphoric after chalking up another success.
“We’re one step closer to uncovering the mysteries of the universe. And I can’t wait to see Webb’s first new views of the universe this summer!” the Nasa administrator, Bill Nelson, said in a statement.
“Wow, what a ride this last month it’s been,” said Amber Straughn, a deputy project scientist for Nasa.
The telescope has been described as a “time machine” by scientists and will enable astronomers to peer back further in time than ever before, all the way back to when the first stars and galaxies were forming 13.7bn years ago. That’s a mere 100m years from the Big Bang, when the universe was created.
The Webb will also hunt for signs of extraterrestrial life.
On 8 January, Nasa engineers completed the unfolding of the telescope, which includes an enormous gold-plated 6.5-metre (21ft) mirror and a tennis-court-sized sunshield. The process required a series of highly delicate and complicated manoeuvres, a choreography that has not been performed by any other spacecraft in astronomic history.
The Webb has been designed as a replacement for the Hubble space telescope, which remains in operation after its 1990 launch. Unlike the Hubble telescope, the Webb will not study the visible aspect of the electromagnetic spectrum. Rather, it will study only infrared radiation. As a result, it has been fitted with complex shielding and advanced cooling equipment to protect its equipment from solar radiation that can trigger misleading signals.
At 1m miles away from Earth, the Webb is over four times as distant as the moon. Last December, Nasa scientists estimated its life span to be “significantly more” than 10 years.
Considered the successor to the Hubble, which orbits 330 miles (530km) up, the Webb is too far away for emergency repairs. That makes the milestones over the past month – and the ones ahead – all the more critical.
Spacewalking astronauts performed repairs five times on the Hubble. The first operation, in 1993, corrected the telescope’s blurry vision, a flaw introduced during the mirror’s construction on the ground.
Whether chasing optical and ultraviolet light like the Hubble or infrared light like the Webb, telescopes can see farther and more clearly when operating above Earth’s distorting atmosphere. That’s why Nasa teamed up with the European and Canadian space agencies to get Webb and its massive mirror – the largest ever launched – out into the cosmos.
• This article was amended on 25 January 2022 to clarify that the Webb is the world’s largest space telescope, not the largest of all telescopes.
The Associated Press contributed to this report
