Ariane 5 VA256 - James Webb Space Telescope - NET 25 December 2021 (12:20 UTC)

[bolun]

November 4, 2019

A milestone payload for Ariane 5: the James Webb Space Telescope is prepared for liftoff with Arianespace

With multiple pre-flight milestones achieved in recent months, the James Webb Space Telescope (JWST) – which will succeed the Hubble Space Telescope – is on course for its historic launch by Arianespace on an Ariane 5.

As the world’s premier space science observatory, the JWST will solve mysteries of the solar system, look for distant worlds, and probe the mysterious structures and origins of the universe. It is an international project led by the U.S. National Aeronautics and Space Administration (NASA) – along with its partners, the European Space Agency (ESA) and Canadian Space Agency (CSA).

Arianespace is performing the launch on behalf of ESA, within the agency’s scope of its collaboration with NASA. The mission – currently planned for 2021 – underscores Arianespace’s ability to serve institutional clients while also expanding humankind’s knowledge of the universe to make life better on Earth.

After deployment by Ariane 5 from the Spaceport in French Guiana, the JWST will travel to near the second Lagrange point (L2) of the Earth-Sun system (1.5 million kilometers from Earth, directly opposite the Sun), where the telescope will circle about the L2 point in a halo orbit.

Fully assembled for launch

Kicking off a series of launch preparation achievements, the two components comprising the JWST – the spacecraft and its telescope – were integrated for the first time in late August. This activity took place at the Redondo Beach, California facilities of U.S.-based Northrop Grumman, which leads the JWST industry team.

After the JWST was mechanically connected, engineers worked to electrically link up its two components – enabling them to “speak” to each other like they will in orbit. This optional risk reduction test, marked in late September, took advantage of an opportunity to electrically connect the two components months earlier than planned.

If any issues had been found during the evaluation, it would have given engineers more time to investigate and troubleshoot. In addition, this test provided a jumpstart for the separate spacecraft and telescope teams to begin working jointly as they will when the JWST is fully completed.

A milestone deployment

In October, the JWST passed a test critical to preparing the observatory for its 2021 Ariane 5 launch from French Guiana: deployment of its sunshield, which will protect the JWST’s mirrors and scientific instruments from light and heat while in orbit.

Shaped like a kite and sized at 22 X 10 meters, the sunshield’s five layers were fully deployed (and put under tension) during this continued activity at Redondo Beach, as engineers and technicians successfully put the sunshield into its operational position.

After the sunshield is returned to its stowed position for flight, the JWST will undergo comprehensive electrical tests, as well as a set of mechanical evaluations to simulate launch vibrations. There will be one final deployment and stowing cycle on the ground before its integration on Ariane 5.

https://www.arianespace.com/mission-update/james-webb-space-telescope-preps/

EDIT zubenelgenubi: James Webb Space Telescope - Discussion and Updates (Thread started in October 2007!)
This is the launch campaign thread.

[bolun]

JWST remains on schedule for March 2021 launch

[zubenelgenubi]

T-1 year and counting?

In late January 2020, the General Accounting Office released a report, "JAMES WEBB SPACE TELESCOPE: Technical Challenges Have Caused Schedule Strain and May Increase Costs."  Launch may be delayed to July 2021.  The updates and discussion start here.

One of the COVID-19 repercussions: NASA and Northrop Grumman suspend integration and testing operations, dated March 20.

EDIT As of March 25, limited work continuing in the short term.

[libra]

Meanwhile Ariane 6 is coming fast, and Ariane 5 must retire at some point...

[Hobbes-22]

IIRC they're going to launch this on an Ariane 5 even if A6 is operational by then.

[woods170]

IIRC they're going to launch this on an Ariane 5 even if A6 is operational by then.

Correct. Arianespace and ESA have an agreement with NASA to keep A5 alive and ready-to-launch until - at least - JWST is ready for launch.

[libra]

thank you, I knew this perfectly already.

IIRC they're going to launch this on an Ariane 5 even if A6 is operational by then.

My point: hopefully that lone Ariane 5 won't become a PITA for Arianespace. In the sense of: disturbing the transition between the two rockets. An odd, obsolete rocket among all those new Ariane 6.

Arianespace however is pretty good at transitioning between generations of Arianes, so I'm not too worried...

How long is Ariane 5 supposed to last once Ariane 6 enter service ? how much overlap ?

[Asteroza]

Perhaps the more accurate question is what is the shelf life of that rocket. Some parts aren't rated for long term storage, thus keeping the supply chain open for those parts is the pain point.

[DaveS]

Considering that both the first  Ariane 5-G and Ariane5-ECA exploded, I think it's safe to say that they're keeping the lines up until Ariane 6 has proven itself. In fact, Rosetta missed its rendezvous with 46P/Wirtanen because of the ECA-1 failure. That's why it was redirected to 67P/Churyumov-Gerasimenko.

[TorenAltair]

The last 10 Ariane 5 were ordered in 2018. They are planned to be used until 2023.

I guess there is an English press release anywhere as well, but so long:
https://www.ariane.group/wp-content/uploads/2018/01/10-Ariane-5-Produktion.pdf

[Rik ISS-fan]

Indeed Arianespace /ESA has planned a transition phase from Ariane 5 to Ariane 6 from 2020 to 2023.
I deem it very unlikely JWST will slip beyond 2023. I think that Ariane 5 launches could be extended until 2024.
But afaik from 2025 Ariane 6 is proven enough for it to launch JWST is postponed this long. Ariane 6 will have launched about 20 times at that point. And I fear that JWST will be terminated when such long postponement is required. Let's hope JWST launches in 2021 or 2022.

[AnalogMan]

The last 10 Ariane 5 were ordered in 2018. They are planned to be used until 2023.

I guess there is an English press release anywhere as well, but so long:
https://www.ariane.group/wp-content/uploads/2018/01/10-Ariane-5-Produktion.pdf

A version in English:
https://www.ariane.group/wp-content/uploads/2018/01/10-A5-Production-kick-off.pdf

[zubenelgenubi]

Cross-post:

Schedule was tight and then COVID-19 struck:

James Webb Space Telescope will “absolutely” not launch in March
"This team has stayed on its toes and pushed this telescope forward."

by Eric Berger - Jun 10, 2020 5:19 pm UTC

On Wednesday, the chief of NASA's science programs said the James Webb Space Telescope will not meet its current schedule of launching in March 2021.

"We will not launch in March," said Thomas Zurbuchen, the space agency's associate administrator for science. "Absolutely we will not launch in March. That is not in the cards right now. That's not because they did anything wrong. It's not anyone's fault or mismanagement."

https://arstechnica.com/science/2020/06/james-webb-space-telescope-will-absolutely-not-launch-in-march/

Also:

NASA and the telescope's prime contractor, Northrop Grumman, are evaluating the schedule going forward. This will include an estimate of when operations can completely return to normal—Zurbuchen said telescope preparation and testing activities are nearing full staffing again—and set a new date for a launch. This schedule review should conclude in July.

"I'm very optimistic about this thing getting off the launch pad in 2021," Zurbuchen said. "Of course, there is still a lot of mountain to climb."

[FutureSpaceTourist]

https://twitter.com/thesheetztweetz/status/1283862855192903680

Steve Jurczyk: JWST new launch date is October 31, 2021.

[bolun]

JAMES WEBB SPACE TELESCOPE TO LAUNCH IN OCTOBER 2021

16 July 2020

The launch of the NASA/ESA/CSA James Webb Space Telescope (Webb) on an Ariane 5 rocket from Europe's Spaceport in French Guiana is now planned for 31 October 2021.

NASA has announced the decision, based on a recently completed schedule risk assessment of the remaining integration and test activities before launch, accounting for impacts from the COVID-19 pandemic and technical challenges. Previously, Webb was targeted to launch in March 2021.

Testing of the observatory continues to go well at Northrop Grumman, the mission's main industry partner in Redondo Beach, California, despite the challenges of the coronavirus situation. The factors for the new launch date include the impacts of augmented safety precautions, reduced on-site personnel, shift work disruption and technical challenges. This year, a final set of complex environmental tests of the full observatory will be completed followed by a final deployment of the telescope and sunshield.

https://sci.esa.int/web/jwst/-/james-webb-space-telescope-to-launch-in-october-2021

Image credit: NASA/Chris Gunn

[FutureSpaceTourist]

https://twitter.com/arianespaceceo/status/1325119563357278209

Arianespace has a dream : to welcome @JoeBiden, elected 👏President of the United States of America, at the Guyana Space Center for the launch of James Webb Space Telescope on 31st October 2021. Yes we can ! @NASA @esa @CNES

[zubenelgenubi]

Cross-post; no change to scheduled launch date:

I got some information about the flights for this year:

<snips>
VA254 - Officially March 4th (most likely late May or June, due to delays related to new modifications to the launcher fairing)
VA255 - Mid-August, IF the VA254 campaign is not delayed any further
VA256 - Officially October 31st, with JWST

There may be another Ariane 5 flight this year, but it's unlikely.

Launcher fairing modifications are a work-in-progress towards the goal of more efficient venting of air pressure during ascent, in support of the JWST launch.

[GWR64]

An article from October at SpaceNews about the fairing problem, among other things.
https://spacenews.com/jwst-remains-on-track-for-october-2021-launch/
Could the fairing separaton be moved back a little, until the remaining air has completely escaped?
That would cost performance. Does Ariane still have reserves for this launch?

[russianhalo117]

An article from October at SpaceNews about the fairing problem, among other things.
https://spacenews.com/jwst-remains-on-track-for-october-2021-launch/
Could the fairing separaton be moved back a little, until the remaining air has completely escaped?
That would cost performance. Does Ariane still have reserves for this launch?

Burn to depletion AFAIU on all stages.

[Jester]

Here is a guess, this will move a couple of days, launching on Sunday at CSG?....nah ;-)