James Webb telescope countdown to launch and first light
Posted: Sat Nov 27, 2021 10:17 pm
by LanDroid
After extremely long delays, massively over budget, and a last minute scary "incident," the James Webb space telescope (JWST) is set to launch 12/22/21. This instrument is optimized for infrared, which will allow it to see much farther than Hubble. It will be able to see galaxies so far away that they have red shifted out of the visible spectrum. It will also be able to see deeper into atmospheres of exoplanets.
The JWST will undergo 30 Days of terror as it maneuvers to the L2 Lagrange point, orbiting the sun. Hundreds of processes need to happen sequentially during that journey, with just as many potential points of failure.
Re: James Webb telescope countdown to launch and first light
Posted: Sat Nov 27, 2021 11:03 pm
by Chris OConnor
How soon after launch will we start seeing images?
Re: James Webb telescope countdown to launch and first light
Posted: Sun Nov 28, 2021 10:44 am
by LanDroid
After the launch there's the "30 days of terror" mentioned before as the telescope gets into position about a million miles from earth to orbit the sun. One of the links above describes an extremely detailed check out and calibration lasting 6 months. Sounds like first light from JWST will be about 7 months after launch or around the end of July. I hope there will be teaser images long before then.
Re: James Webb telescope countdown to launch and first light
Posted: Fri Dec 24, 2021 4:47 am
by LanDroid
Originally targeted to launch in 2007, it has been delayed again, but this time just due to weather. It's now scheduled for Christmas morning.
After more than two decades of development, NASA's next-generation space telescope is on the launch pad. The James Webb Space Telescope is due to launch on Saturday (Dec. 25) during a 32-minute window that opens at 7:20 a.m. EST (1220 GMT). The massive observatory will blast off from Kourou, French Guiana, atop an Ariane 5 rocket operated by European launch provider Arianespace. You can watch launch coverage live at Space.com beginning at 6 a.m. EST (1100 GMT) courtesy of NASA or you can watch directly at the agency's website.
Re: James Webb telescope countdown to launch and first light
Posted: Sat Dec 25, 2021 7:25 am
by LanDroid
I just watched the launch live. SUCCESS!
Let the "Thirty Days Of Terror" begin!
Re: James Webb telescope countdown to launch and first light
Posted: Sat Dec 25, 2021 9:19 am
by Chris OConnor
My son and I watched too!
Re: James Webb telescope countdown to launch and first light
Posted: Sun Dec 26, 2021 1:36 am
by LanDroid
The massive observatory launched today (Dec. 25) from Europe's Spaceport in Kourou, French Guiana, at 7:20 a.m. EST (1220 GMT). Just 12.5 hours later, the spacecraft began a vital maneuver on its month-long journey to its future outpost as the observatory executed a 65-minute-long thruster burn that concluded at 8:55 p.m. EST (0155 GMT), according to a statement from NASA.
...According to NASA, this burn, dubbed Mid-Course Correction Burn 1a or MCC1a, was the most important of the three burns the spacecraft will make during its journey to L2, and the only one that needed to be particularly carefully timed. https://www.space.com/james-webb-space- ... ctory-burn
One less day of terror...
Re: James Webb telescope countdown to launch and first light
Posted: Sun Dec 26, 2021 12:53 pm
by LanDroid
Here's an 8-minute video called 29 Days on the edge summarizing the extremely complicated actions that must execute flawlessly for JWST to operate. Right about now the instrument is probably passing the moon, speeding to the L2 LaGrange point.
There's more detail in the following article.
Two to three months after launch, for instance, the team will align the primary mirror segments so they act as a single light-collecting surface. This will be painstaking and time-consuming work, for the mirror has to be perfect to an accuracy of 150 nanometers. (For perspective: A sheet of paper is about 100,000 nanometers thick.)
"One of our scientists calculated that we move those mirrors literally slower than grass grows as we're lining them up so incredibly precisely," Webb Deputy Senior Project Scientist Jonathan Gardner, of NASA's Goddard Space Flight Center in Greenbelt, Maryland, told Space.com earlier this month.
Re: James Webb telescope countdown to launch and first light
Posted: Fri Dec 31, 2021 5:37 am
by LanDroid
Here's a status page, showing video simulations of the latest activity, temperatures from various spots including the mirrors, etc. At this point the hot side averages +82F. The mirrors on the cold side are still quite warm at -49F but I expect will drop quickly once the sunshield is fully deployed during the next few days. Not sure how cold they will get, possibly close to absolute zero. Oh, and it currently is at 47% of the way to the final destination.
Re: James Webb telescope countdown to launch and first light
Posted: Mon Jan 03, 2022 7:40 pm
by LanDroid
The sunshield has been opened. In the next few days the five layers will be tensioned and separated for max heat shielding. The temperature of the mirrors has dropped from -49F in previous post to -177F currently. Deploying mirrors into final configuration is next. The telescope is 61% of the distance to the final destination.
