The biggest space mission of 2021.
The Hubble Space Telescope provides key data and has allowed for many scientific studies. It's strategic position above the Earth's atmosphere gives it an excellent position to view the universe. But recently it has had many technical difficulties, including being unable to operate for over a month. The good news is that NASA has been working on a replacement since a few years after Hubble launched. The replacement is unlike anything that humans have ever built [1].
The original plan was for the James Webb Space Telescope to launch in 2007 and cost a billion dollars [2]. Due to the complexity of the telescope, the launch date has been delayed many times. Some people have even nicknamed it the “Just Wait Space Telescope.” It is now currently scheduled to launch in a few weeks. In total, the JWST has cost nearly 10 Billion dollars.
The telescope itself is a large mirror made up of 18 hexagonal mirrors that are coated in gold. They reflect light onto a secondary mirror on a large outstretched beam which sends light to the center of the telescope, where the four science instruments can detect the light. In order to keep the instrument ultra-cold, the large sunshield prevents sunlight from heating up the telescope. Beneath the sunshield, there are thrusters to steer the telescope and solar panels to power it [3].
The JWST has a primary mirror 6.5 meters in diameter, which is well over twice the size of Hubble’s 2.4 meter mirror. This will allow JWST to see some of the universe's first galaxies. Unlike Hubble, JWST won’t be able to see visible or ultraviolet light. It only has the capability to see infrared light. Like Hubble, JWST is an international collaboration. The European Space Agency (ESA) provided the launch vehicle and helped with two of the science instruments. The Canadian Space Agency also contributed by building one of the instruments [4].
The James Webb Space Telescope is currently a few weeks away from launching. It is in final processing in French Guiana and is scheduled to launch on an Ariane 5 on December 18th. Due to the telescope's insane size, it has to be folded up into the rocket like origami. Once in space it will navigate to L2, a point of stability outside of Earth orbit, then it will spend 29 days slowly unfolding. Eventually, the groundbreaking science will begin [5].
The James Webb Space Telescope might be the most complicated item that humans have ever launched out of Earth orbit. It is a marvel of engineering that has pushed the limits of human technology.
To learn more about JWST, I'd recommend viewing this detailed PDF from the European Space Agency
I'd also recommend these two YouTube Videos
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