The James Webb Space Telescope

[valenumr]

Maybe this is more general discussion, but I am excited / nervous about the upcoming launch of the JWST.

https://jwst.nasa.gov/content/webbLaunch/countdown.html

I can't wait to see the observations this endeavor will bring!

 

[fresh_42]

The how many-th countdown is that?

 

[valenumr]

The how many-th countdown is that?

To be fair, the weather forecast kind of sucks. Looks like a couple straight weeks of thunderstorms.

 

[Hamiltonian]

There is about one week left for the launch!
NASA's long-awaited space observatory is now scheduled to lift off no earlier than Dec. 24, two days later than previously planned. I have been waiting for about 2years now(I think there are some people who have been waiting since 2005 and some even earlier than that!), although I am no astronomer I am really looking forward to the data that the JWST will send back, and the conclusions we will be able to draw from them, that would of course mean waiting for 6 more months for the telescope to be put into orbit. Let's just hope everything goes smoothly

https://www.space.com/james-webb-space-telescope-launch-delay-december-24

 

[valenumr]

There is about one week left for the launch!
NASA's long-awaited space observatory is now scheduled to lift off no earlier than Dec. 24, two days later than previously planned. I have been waiting for about 2years now(I think there are some people who have been waiting since 2005 and some even earlier than that!), although I am no astronomer I am really looking forward to the data that the JWST will send back, and the conclusions we will be able to draw from them, that would of course mean waiting for 6 more months for the telescope to be put into orbit. Let's just hope everything goes smoothly

https://www.space.com/james-webb-space-telescope-launch-delay-december-24

Apparently, there is a window up to January 6th where it can launch, then I guess the moon becomes problematic gravitationally. I hope it successfully launches before then.

 

[stefan r]

There should still be a reconning even if it does work. The wait was too long and the price tag too high.

I do hope that all will be well and we get a return on most of that expense.

With enough billions we can advance to in-space construction. We might not get a better scope in that generation. However, once the capability is there we can increase reflector size by 3 (or 5, or 11?) orders of magnitude.

Many missions were scrapped to keep funding going into JWST. It is inherently a gamble. A lucky outcome when you roll the dice does not mean you do not have a gambling problem.

 

[DennisN]

Maybe this is more general discussion, but I am excited / nervous about the upcoming launch of the JWST.

Same here!

I can't wait to see the observations this endeavor will bring!

Same here!

 

[sophiecentaur]

I was reading the update on the JWSP progress and I noted that there is more to finding a suitable window than getting the right time of day! In any case that would be a massive consideration for getting near L2 but there's a lot more to it than that. It's all the same old criteria: right place, right time, right speed (+ some others).

This link is from NASA and it makes good reading. Loads of graphics that sort of explain the problem. I guess the main problem is that they don't want to use up more of the payload than necessary with fuel.

This link

 

[valenumr]

T minus 76 hours!

 

[pinball1970]

T minus 76 hours!

https://jwst.nasa.gov/content/webbLaunch/countdown.html

This is great!

 

[Astronuc]

The Verge has an interesting article on how JWST has developed and how it has been allocated during the first year.
https://www.theverge.com/22789561/n...-priorities-astronomy-astrophysics-exoplanets

The program used a double anonymous review process. The submitters didn't know who would review, and the reviewers did not know the authors.

After painstaking debate, the committee selected the proposals it found to be the most transformative. It then gave each proposal a certain number of hours of observation time. Ultimately, STScI selected a total of 266 proposals, submitted by scientists from 41 countries around the globe.

Caitlin Casey, an astronomer at the University of Texas, was having a very different kind of Blacker Friday. She was at home in Austin, holding her sleeping two-month-old baby in her lap, while scrolling her phone. That’s when she saw the email pop up in her inbox.

“Dear Dr. Casey,

We are pleased to inform you...”

The ambitious project she and her team had proposed, called Cosmos Web, had just been approved. And the Institute was giving Casey a whopping 208 hours with JWST to fulfill her project, the most of anyone who had submitted proposals. The project will stare at a particularly large patch of sky the size of three full Moons, an area that spans up to 63 million light years across. Doing so will create a portrait of the young universe similar to the Hubble’s iconic Hubble Deep Field, which showcased some of the earliest galaxies we could observe at the time. With JWST’s enhanced capability, the team will be imaging galaxies that are even older at even greater levels of detail. “If the Hubble Deep Field were printed on an eight-and-a-half by 11 sheet of paper, Cosmos Web would be like a 16-foot by 16-foot mural on the side of a building,” says Casey.

Aside from Cosmos Web, the seven-planet TRAPPIST-1 system will be getting a lot of attention during JWST’s first year, with up to seven different programs dedicated to studying this strange cluster of worlds.

Roughly 10,000 hours of observing time is allotted to different groups for JWST’s first year of life. About 6,000 hours were given to the scientists who submitted proposals around the world, while nearly 4,000 hours were already set aside for scientists who helped design and build JWST and its instruments. The STScI also has about 460 hours of discretionary time which have been allotted for what is known as “Early Release Observations.” Data from these hours, scheduled to be done in the first five months of science, will become public immediately, so that anyone — even those who did not get time with the telescope — can analyze the observations and write their own studies.

Anyone who does the math will realize that 10,000 hours is actually more than the number of hours in a calendar year. STScI purposefully overprescribed JWST’s time to account for any snafus. STScI will be scheduling JWST’s observations in two-week increments, during which time the observatory will point at its intended targets autonomously. However, it’s possible that JWST will fail to execute some commands properly from time to time. If that happens, JWST will simply go on to the next observation.

 

[valenumr]

Looks like there will be a weather delay

 

[collinsmark]

Here's a video that I think most people here will enjoy.



There's a bit of a misleading animation around 4:55 (and the script wording doesn't help), and a big error in the wording that must have slipped by the proofreading at right around 19:00 (for which I'm betting the author is kicking himself), but it's still an overall good video.

 

[Hamiltonian]

The official JWST mission trailer

 

[Melbourne Guy]

There should still be a reconning even if it does work. The wait was too long and the price tag too high.

The Big Picture Science podcast discussed this aspect, @stefan r, it's interesting listening, it seems success overrides budget for NASA missions!

http://bigpicturescience.org/episodes/hubble-and-beyond

 

[DennisN]

Here's a video that I think most people here will enjoy.

Thanks for posting! Great video and the technology is just amazing!

Somewhere in the video it was said that they originally wanted a bigger mirror.
Hehe, aperture fever is a real thing, even for the JWST team.

 

[Filip Larsen]

Regarding the JWST and its capability for science missions I found the following really enlightening:

 

[DennisN]

Regarding the JWST and its capability for science missions I found the following really enlightening:

Thanks for the Christmas gift! I will watch this later today!

 

[DennisN]

Hehe, I've just set three alarms on my clock for the launch (which I suppose will be shown here: https://www.nasa.gov/nasalive).

I don't normally set my alarm for things on TV, but for JWST I made an exception.

I just also wondered if there is an onboard camera (I was thinking for filming/monitoring the deployment process).

I searched for it but I could not find any more info than 1) this stackexchange thread that says "no" and 2) another stackexhange thread about visible spectrum cameras on the JWST in general ("no").

 

[valenumr]

Hehe, I've just set three alarms on my clock for the launch (which I suppose will be shown here: https://www.nasa.gov/nasalive).

I don't normally set my alarm for things on TV, but for JWST I made an exception.

I just wondered if there is an onboard camera (I was thinking for filming the deployment process).
I searched for it but I could not find any more info than 1) this stackexchange thread that says "no" and 2) another stackexhange thread about visible cameras in general.

Ugh. I think it is 220am for my local time. I hope I'm awake, and I hope not to be disappointed.

 

[fresh_42]

Hehe, I've just set three alarms on my clock for the launch (which I suppose will be shown here: https://www.nasa.gov/nasalive).

I don't normally set my alarm for things on TV, but for JWST I made an exception.

I just also wondered if there is an onboard camera (I was thinking for filming/monitoring the deployment process).

I searched for it but I could not find any more info than 1) this stackexchange thread that says "no" and 2) another stackexhange thread about visible spectrum cameras on the JWST in general ("no").

It will be noon over here.

High Noon?

 

[valenumr]

Well, this just happened:

Signs...

 

[valenumr]

Well, this just happened: View attachment 294691

Signs...

I was walking over to get lunch from my favorite Vietnamese place and this happened in my face. I'm not commenting on this thread any further until JWST is on an L2 trajectory. I'm not superstitious, but right now I'm superstitious.

 

[DennisN]

Here's a "better" livestream (directly on youtube, which means it can be put in fullscreen mode):

NASA Live: Official Stream of NASA TV (link)

​

 

[berkeman]

I was walking over to get lunch from my favorite Vietnamese place and this happened in my face.

So the restaurant didn't have a drive-through window before?

 

[valenumr]

So the restaurant didn't have a drive-through window before?

Outdoor dining seems popular.

 

[valenumr]

Outdoor dining seems popular.

Darn it no more comments for twelve hours!

 

[collinsmark]

Here's a Scott Manley video that discusses some of the more technical aspects of the JWST, including some of the instrumentation on board, and explains why the JWST has a limited viewing area of the sky at any point in time (the sun shield must be pointed toward the sun, after all).

 

[mfb]

7 hours 45 minutes. It is now 4:35 GMT and the launch is scheduled for 12:20 GMT.

Spaceflight Now has a timeline of the events up to the launch.
Propellant loading of the core stage will begin 7:42 GMT, loading the upper stage will follow 8:52. NASA will start its coverage at 8:00 GMT.
The final weather briefing will come only 10 minutes before launch.

At t=0 the liquid fuel engine of the core stage will ignite for final checks, the solid fuel boosters will be ignited 7 seconds later if everything is healthy. It will sit on the launch pad during these 7 seconds, that is normal. Liquid fuel engines can be shut down again, solid fuel engines cannot. Once they are ignited JWST will go somewhere.

 

[DennisN]

I just also wondered if there is an onboard camera (I was thinking for filming/monitoring the deployment process).

I searched for it but I could not find any more info than 1) this stackexchange thread that says "no" and 2) another stackexhange thread about visible spectrum cameras on the JWST in general ("no").

I just remembered I've got a working webcam I don't use. It's a HD camera and reasonably good, I think. Should I offer it to the JWST team as an onboard camera? Or maybe it's a little late for that?

 

[mfb]

Booster propellant loading should have started.
NASA coverage of the launch procedure has started, although it's just a video of the rocket for now.



Edit: Confirmation that propellant load is ongoing.

 

[pinball1970]

Thanks for the Christmas gift! I will watch this later today!

Happy JWST day! T minus 4 ish hours and counting and it's 8.48am here in this corner of excited sunny Manchester! (And merry Yule or something too)

 

[pinball1970]

My NASA link is not working. This one seems ok.
The wildlife will be traumatized, hopefully run fly off as things start up.
https://spaceflightnow.com/2021/12/25/ariane-5-va-256-jwst-mission-status-center/

 

[Borg]

30 minutes...

 

[fresh_42]

30 minutes...

Livestream says 90 minutes.

 

[Borg]

Livestream says 90 minutes.

20 minutes according to this livestream from NASA.
https://www.nasa.gov/content/live-coverage-of-nasa-spacexs-24th-cargo-launch-to-the-space-station

 

[mfb]

Then refresh it. 20 minutes now.

185,000 viewers here:


10 minutes until the final weather briefing, 13 minutes until the rocket takes control of itself.

 

[DennisN]

Then refresh it. 20 minutes now.

You beat me to it.

 

[Borg]

20 minutes according to this livestream from NASA.
https://www.nasa.gov/content/live-coverage-of-nasa-spacexs-24th-cargo-launch-to-the-space-station

FYI, the other streams are 10+ seconds behind my link.

 

[mfb]

Final 7 minutes. Weather is good, the synchronized countdown sequence has begun where the rocket takes care of most of its operations. Fuel loading is almost complete, a little bit of venting can be seen.

 

[DennisN]

Ok, time to wish the James Webb Space Telescope a safe flight and all the best!

 

[Borg]

2 minutes to go.

 

[mfb]

450,000 watching the NASA stream as the launch is less than a minute away.

 

[mfb]

And it's flying...

 

[Borg]

Not updating yet but here's a page for the post-launch sequences.
https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html

 

[mfb]

Changing too rapidly during launch I guess.

Approaching first stage separation.

 

[Borg]

Just needed to read further.

NOTE: speed and distance data becomes available on the Where Is Webb? page after upper stage separation. Temperature data becomes available 1-2 days after launch.

 

[Borg]

Now 10 times higher than Captain Kirk has gone.

 

[mfb]

Second engine cutoff. Separation in about 2 minutes. Trajectory is still nominal: It will go to L2.

Edit: Separation. Ariane 5 did its job, JWST is on its own.

 

[Borg]

Separated and leaving earth!

BEST CHRISTMAS PRESENT EVER!