NASA - James Webb Space Telescope - Updates Thread

[gongora]

Updates for the James Webb Space Telescope mission.

[hoku]

" ... passed the altitude of the Moon ..."

Next up: Forward Sunshield Pallet deployment at L+3 days

https://twitter.com/NASAWebb/status/1475637156995551235

[bolun]

Related NSF threads:

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

- https://forum.nasaspaceflight.com/index.php?topic=49417.0

- NASA - James Webb Space Telescope - Discussion and Updates

- https://forum.nasaspaceflight.com/index.php?topic=10453.0

- NASA - James Webb Space Telescope - Discussion Thread 2

- https://forum.nasaspaceflight.com/index.php?topic=54269.0

- Potential servicing missions for the Webb

- https://forum.nasaspaceflight.com/index.php?topic=55292.0

[hoku]

Forward Pallet Structure Lowered, Beginning Multiple-Day Sunshield Deployment

https://blogs.nasa.gov/webb/2021/12/28/forward-pallet-structure-lowered-beginning-multiple-day-sunshield-deployment/
https://twitter.com/NASAWebb/status/1475902474275991554

[Lee Jay]

Aft Sunshield Pallet Deployed

https://blogs.nasa.gov/webb/2021/12/28/aft-sunshield-pallet-deployed/

[Lee Jay]

Webb has extra fuel because of an accurate launch - fuel for longer than 10 years of science.

https://blogs.nasa.gov/webb/2021/12/29/nasa-says-webbs-excess-fuel-likely-to-extend-its-lifetime-expectations/

[Lee Jay]

Webb Team Begins Process of Extending Deployable Tower Assembly

https://blogs.nasa.gov/webb/2021/12/29/webb-team-begins-process-of-extending-deployable-tower-assembly/

This is about a 2 meter extension.

[redliox]

Webb Team Begins Process of Extending Deployable Tower Assembly

https://blogs.nasa.gov/webb/2021/12/29/webb-team-begins-process-of-extending-deployable-tower-assembly/

This is about a 2 meter extension.

Supposed to be a roughly 6 hour process.  If things have gone well this step should be nearly done now.  Encouraging thus far.

[centaurinasa]

https://twitter.com/NASAWebb/status/1476310220079083520

[dccraven]

The NASA blog says that the DTA extended 1.22 meters during this effort today. Earlier descriptions indicated that the DTA should extend 2 meters. Is this a problem?

[Lee Jay]

There's a blog post as well:

https://blogs.nasa.gov/webb/2021/12/29/webbs-deployable-tower-assembly-extends-in-space/

"The DTA extended about 48 inches (1.22 meters), putting room between the upper section of the observatory, which houses the mirrors and scientific instruments, and the spacecraft bus, which holds the electronics and propulsion systems. This creates enough distance to allow the sensitive mirrors and instruments to cool down to the necessary temperatures to detect infrared light. This gap will also provide room for the sunshield membranes to fully unfold."

[Perchlorate]

There's a blog post as well:

https://blogs.nasa.gov/webb/2021/12/29/webbs-deployable-tower-assembly-extends-in-space/

"The DTA extended about 48 inches (1.22 meters), putting room between the upper section of the observatory, which houses the mirrors and scientific instruments, and the spacecraft bus, which holds the electronics and propulsion systems. This creates enough distance to allow the sensitive mirrors and instruments to cool down to the necessary temperatures to detect infrared light. This gap will also provide room for the sunshield membranes to fully unfold."

The paragraph immediately preceding says:

"This afternoon, the Webb team successfully extended the observatory’s Deployable Tower Assembly (DTA), creating critical distance between the two halves of the spacecraft."

They seem to be affirmatively declaring it to be enough.  The overall, deployed height is about 10'.  Perhaps anywhere in the 1.25' to 2' range of extension is sufficient?

[whitelancer64]

The NASA blog says that the DTA extended 1.22 meters during this effort today. Earlier descriptions indicated that the DTA should extend 2 meters. Is this a problem?

Every reference I can find to "2 meters" for the deployable tower are all "about 2 meters"

So I would guess those references are rounding up.

I found a reference from June 2020, a NASA post on the tower's on-ground deployment test.
During the test, the tower was slowly extended 48 inches (1.2 meters) upward over the course of several hours, in the same maneuver it will perform once in space."

https://www.nasa.gov/feature/goddard/2020/tower-extension-test-a-success-for-nasa-s-james-webb-space-telescope

[dsmillman]

Webb’s Aft Momentum Flap Deployed

Shortly after 9 a.m. EST today, the Webb team completed deployment of the observatory’s aft momentum flap. In a process that took about eight minutes, engineers released the flap’s hold-down devices, and a spring brought the flap into its final position.

The aft momentum flap helps minimize the fuel engineers will need to use throughout Webb’s lifetime, by helping to maintain the observatory’s orientation in orbit. As photons of sunlight hit the large sunshield surface, they will exert pressure on the sunshield, and if not properly balanced, this solar pressure would cause rotations of the observatory that must be accommodated by its reaction wheels. The aft momentum flap will sail on the pressure of these photons, balancing the sunshield and keeping the observatory steady.

Just as a ship’s mast must be set in position and the rigging established before the ship unfurls its sails, Webb’s pallet structures, momentum flap, and mid-booms will soon all be in place for Webb’s silver sunshield to unfold. The next steps in Webb’s planned deployment timeline are outlined here.

[ladybower]

https://blogs.nasa.gov/webb/2021/12/30/webb-team-releases-sunshield-covers/

"Webb’s engineers have released and rolled up the sunshield covers that protected the thin layers of Webb’s sunshield during launch. After the team electrically activated release devices to release the covers, they executed commands to roll the covers up into a holding position, exposing Webb’s sunshield membranes to space for the first time.

The deployment, which took about an hour, concluded at approximately 12:27 p.m. EST.

In their next stages of planned activities, engineers will deploy the sunshield mid-booms, before proceeding with sunshield tensioning."

[dsmillman]

For those who want more JWST coverage than a couple of Blog posts a day:

    December 30, 2021
MEDIA ADVISORY M21-171
NASA Plans Coverage of Webb Space Telescope Deployments
 
Thousands of parts must work correctly, in sequence, to unfold NASA’s James Webb Space Telescope into its final configuration, all while it flies to a destination nearly 1 million miles away.
Credits: NASA/Chris Gunn
Over about the next two weeks, NASA will provide broadcast coverage, a media briefing, and other updates on major deployment milestones for the James Webb Space Telescope, the world’s largest and most powerful space science telescope.
Broadcasts of milestone events will air live on NASA TV, the NASA app, and the agency’s website.
Webb, an international partnership with the ESA (European Space Agency) and the Canadian Space Agency, launched Dec. 25 from Europe’s Spaceport in Kourou, French Guiana. The observatory had been folded up, origami style, to fit inside an Arianespace Ariane 5 rocket for launch. Webb is now in the complex and intricate process of unfolding in space, as it travels nearly 1 million miles to its destination, the second Lagrange point or L2.
Webb’s deployment sequence is a human-controlled process that provides the team with the flexibility to pause, assess data, and adjust as needed. The timing and order of all milestones may therefore change. NASA will host live broadcast coverage to mark the following milestones, with specific times and dates updated as they approach:
•   Sunshield tensioning: The full deployment of the sunshield, the most challenging element for Webb, will mark a critical milestone for the mission. This step is scheduled for completion about eight days after launch, no earlier than Sunday, Jan. 2.
•   Secondary mirror support structure deployment: The support structure that holds the secondary mirror in position to focus light collected by the primary mirror is set for deployment about 10 days after launch, no earlier than Tuesday, Jan. 4.
•   Webb deployments complete: With the unfolding of the second of Webb’s primary mirror wings, the Webb team will have completed all observatory deployments. This is scheduled to take place about 13 days after launch, no earlier than Friday, Jan. 7.
NASA provides regular updates on the Webb telescope blog. The public can also follow Webb’s deployments online via a “Where is Webb?” interactive tracker and a Deployments Explorer.
NASA Press Briefing
NASA will hold a media briefing as soon as possible after the end of the live broadcast coverage of Webb’s final deployments. The agency will determine the timing of this briefing as final deployments approach and stream the event live on its website.
NASA’s media accreditation policy for virtual activities is available online.
Social Media Engagement
Members of the public can stay connected with the mission and let people know about Webb’s deployments on Twitter, Facebook, and Instagram with #UnfoldTheUniverse. Follow and tag these accounts:
•   Twitter: @NASA, @NASAWebb
•   Facebook: NASA, NASAWebb
•   Instagram: NASA, @NASAWebb

Additional Webb Resources:
•   Digital media kit
•   Image and video galleries
•   Media interview request form
The Webb mission will explore every phase of cosmic history – from within the solar system to the most distant observable galaxies in the early universe, and everything in between. Webb will reveal new and unexpected discoveries and help humanity understand the origins of the universe and our place in it.
For more information about the Webb mission, visit:
https://webbnasa.gov
-end-
    Press Contacts
Alise Fisher / Natasha Pinol
Headquarters, Washington
202-358-2546 / 202-358-0930
[email protected] / [email protected]
Laura Betz 
Goddard Space Flight Center, Greenbelt, Md.
301-286-9030
[email protected]


    

[centaurinasa]

https://twitter.com/NASAWebb/status/1476645154656333824

[centaurinasa]

https://twitter.com/SpaceflightNow/status/1476930981978378241

[centaurinasa]

https://twitter.com/SpaceflightNow/status/1476943363677032455

[centaurinasa]

https://twitter.com/cbs_spacenews/status/1476941044495405059
https://twitter.com/cbs_spacenews/status/1476941303258746907
https://twitter.com/cbs_spacenews/status/1476942626700070912