High cost astronomy

[Jlabute]

Just an FYI... the James Webb telescope has been packed up and shipped to a launch site. Last I heard, the launch date will be this December.

[Jlabute]

Yeah. I can’t imagine the tears if it fails to launch, fails to travel a million miles, and fails in the numerous processes to unfold and work. Seems like a long shot even after 20 years of preparation.. yet, there have been many successful missions. Fingers crossed!

Seeing the French will be launching it, do you think they will take their sub-revenge? lol

[GordonH]

Just an FYI... the James Webb telescope has been packed up and shipped to a launch site. Last I heard, the launch date will be this December.

Countdown is at 9 days 8 hours and few minutes away liftoff.
https://jwst.nasa.gov/content/webbLaunch/index.html

[oneh2obabe]

Set to take flight Christmas Eve if all goes well.

[Jlabute]

Appears to be the 25th due to weather. 1 day 18h to go from this post.

[JagXKR]

https://jwst.nasa.gov/content/about/launch.html

Webb's launch date is set for December 25, 2021 07:20am EST ( 2021-12-25 12:20 GMT/UTC).

https://www.timeanddate.com/worldclock/ ... ana/kourou
4:20am PST 9:20am GFT (local)

[JagXKR]

Good launch. All parameters nominal. Enroute L2.

It was great to see the solar panel extend just before the upper stage camera lost picture.
Now just over 300 more things to go right.....

[JagXKR]

https://twitter.com/NASA/status/1474725 ... 81698?s=20

[Jlabute]

JWST is off to L2 Lagrange. I can’t even remember how long I’ve been waiting to see this. Lift-off went in to thick clouds, but was still exciting to watch all involved and camera feedback.

[Jlabute]

https://www.jwst.nasa.gov/content/webbL ... sWebb.html

17:16 PST - 100,000 miles.

[GordonH]

Meteor could cause this item to be a 10 billion dollar piece of space junk, probably causes finance department monster ulcers.

[oneh2obabe]

Canadian scientists involved in James Webb space telescope say it's a dream come true.

René Doyon, principal investigator of the telescope, said seeing the launch in-person was the best Christmas gift he could have ever hoped for. COVID-19 requirements meant most Canadian scientists who worked on the project had to stay home.

“It was an intense moment, absolutely incredible emotions after 20 years of working on the project,” Doyon said in an interview Saturday.

“I could have never imagined that it would have happened on Christmas. It was a good moment for Canada."

Nathalie Ouellette, outreach scientist for the Webb at the Université de Montréal, was with her family watching the long-awaited launch in Montreal.

"To see the telescope leave Earth … what a joy for Christmas," Ouellette said.

"I cried. We took a video to commemorate the moment. The launch went perfectly."

https://www.msn.com/en-ca/news/canada/c ... hp&pc=U531

[Sonny Taylor]

https://www.jwst.nasa.gov/content/webbL ... sWebb.html

17:16 PST - 100,000 miles.

Some thoughts for technically minded folks; I hope my understanding is near correct...

It's interesting watching JWST's speed decrease over time on it's way to the L2 Lagrange point orbit.

That orbit is almost at edge of the Earth's "Hill Sphere" (the sphere in space within which the Earth's gravity dominates that of the Sun's).

So the launch rocket (quickly) shot JWST to just enough speed to make it, coasting to the edge of Earths gravitational influence. As JWST coasts "up hill" it should continuously decelerate (not withstanding course corrections).

From shortly after launch it's speed has dropped from over 4 miles per second to 1.1 (as of 3:00 am Sunday 26-Dec). That's a huge drop in speed in a hurry; but it makes sense that it would encounter the most deceleration closest to the Earth (re: Newton's Inverse-square law)

So now as it moves further from Earth I expect the rate of deceleration to drop dramatically (ie; the speed will change much slower). I think I finally grasp why the trajectory to L2 will take a month to arrive. I also found it interesting that this is a direct trajectory without use of an intermediate Earth parking orbit.

Hope I didn't bore you.

[Sonny Taylor]

Good thing the moon is almost on the Sun facing side of the Earth now so it won't interfere with JWST's trajectory on the night side of Earth.

"New Moon" is one week away. By the time of the next full moon on 17-Jan (Moon on the same side of Earth as JWST), JWST will have passed well beyond it's orbit already and be relatively unaffected by it's gravity.

[Jlabute]

So now over 200,000 miles. Yippeeeee