On Christmas night, from a spaceport in French Guiana in South America, NASA's newest space telescope, the James Webb Space Telescope, was launched.
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Nervous eyes from astronomers all around the world watched as it took off into space. The launch was almost textbook, so much so they have saved enough fuel to extend the lifetime of the telescope by an extra 10 years.
It was then the really tricky work started.
Telescopes are measured by how big or wide the mirror is. The size of the mirror is what matters, as they are essentially giant light buckets. The bigger the bucket, the more light you can collect, allowing you to see fainter, and therefore further light.
The mirror size of the James Webb is 6.5 metres, much bigger than the Hubble Space Telescope's mirror of 2.4 metres. When the Hubble Space Telescope was built, it was designed to fit inside the Space Shuttle, which could fit a telescope with a mirror 2.4 metres wide. Any bigger and it would not have fit.
The James Webb went up on an Ariane 5 rocket, which can fit objects up to 4.57 metres wide. This was always going to be a problem, either the telescope would need to be smaller, or built in a way that it could fit inside. Engineers and scientists went with the latter option, and decided to build a telescope that could be folded to fit.
Once the James Webb Space Telescope was launched, it had to start a process over the next few weeks of slowly unfolding in space. Not just the mirror, but the support structure for the secondary mirror which is the part of the telescope that focuses the light had to be folded.
There are also the massive sunshields, which blocks light from the Sun, like a giant beach umbrella. This keeps the telescope very cold, so that it can detect very faint infrared light. If not, the light and heat from the Sun would dominate the telescope and it wouldn't see much.
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The sunshield is about the size of a tennis court, about 21 metres long and 14 metres wide, which also had to be folded.
About 50 major manoeuvres and steps, along with many smaller steps, have been performed on the James Webb Space Telescope. Almost all of these steps have never been done before in order to get this telescope up and running.
After weeks of round-the-clock work from a dedicated team, the telescope has done all of these steps and made it through the most difficult parts.
There is still a lot of work to go before we start getting beautiful images from the telescope. The mirror is made up of many smaller segments, which are adjustable. NASA is now moving all of these segments to get the best focus. A lot like going to the optometrist, "is one or two better".
The telescope will then have to be cooled, to allow the cameras to work at the right temperature. The cameras and instruments will then need to be tested, calibrated, and checked, followed by lots of testing.
We all are excited to see the first pictures from the James Webb Space Telescope.
Thanks to the thousands of engineers, technicians, and scientists who spent years building, testing, and re-testing along with those who have been working non-stop since Christmas, we are getting really close to see the universe in a whole new light.
- Brad Tucker is an astrophysicist and cosmologist at Mount Stromlo Observatory, and the National Centre for the Public Awareness of Science at ANU.