Credit：NASA/Bill Ingalls
The James Webb Space Telescope (JWST) is scheduled to launch at 20:20 Beijing time on December 25 at the European Spaceport in Kourou, French Guiana.
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Once known as the "Next Generation Space Telescope," the James Webb Space Telescope was named in 2002 after NASA's second director, James Edwin Webb, who led a number of major U.S. space exploration programs, including the Apollo program.
Credit：NASA
The Webb Space Telescope was jointly developed by NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA) in 1996 with a budget of $500 million, and was originally scheduled to launch in 2007, but due to repeated delays, it was dubbed the Ace Pigeon Telescope. After multiple delays and cost overruns, Ace pigeons adjusted for inflation into 2020, the final cost of the Webb Space Telescope is about $10.8 billion.
Credit:ESA
The Webb Space Telescope is an infrared telescope whose main focus is on spectroscopy. Hubble is observed in visible light. The main mirror of the Webb Space Telescope is 6.5 meters in diameter, is divided into 18 mirrors, weighs a total of 6173 kg, has a design life of more than 10 years, and operates in the 0.6 micron to 28.5 microns, and will be placed at the second Lagrange point (L2 point) of the helio-Terrestrial system 1.5 million kilometers from Earth after launch.
The folded Webb Space Telescope is 10.66 meters high and 4.5 meters wide, and is placed in a fairing with a height of 17 meters and a diameter of 5.4 meters.
The unfolded Webb Space Telescope is 8 meters high, 21.2 meters long and 14.2 meters wide, and in space, the webb space telescope's sun visor is about 85 degrees Celsius on the sun-facing side and minus 233 degrees Celsius on the back-facing side of the sun.
The following video is the 0th episode of the "Webb ElementAls" series of short films, why does Webb have a golden mirror? Subtitle Production: Wow.
Within a month of liftoff, the telescope was deployed; after more than a month, it was fully deployed and into L2 orbit; two to three months, the instrument was turned on; four to six months, the instrument was tested; and six months later, scientific observations were made.
The Webb Space Telescope will observe Hubble's extremely deep field in its first year, and it would take Less than a day for Webb to be more distant than Hubble could see in two weeks. To look at celestial objects with a telescope is to look at the past, for example, what we see on Earth is the moon 1.26 seconds ago, the sun 8 minutes ago.
If the time when the universe began to now is compared to a year, if the time is 11:55 p.m. on December 31, then the Webb Space Telescope can see back to January 6.
reference
[1]https://www.planetary.org/articles/cost-of-the-jwst
[2]https://svs.gsfc.nasa.gov/Gallery/JWST.html
[3]https://www.esa.int/Science_Exploration/Space_Science/Webb/Webb_s_instruments