Author Topic: NASA - James Webb Space Telescope - Updates Thread (Read 336454 times)

Lee Jay · « **Reply #40 on:** 01/03/2022 05:38 pm »

Quote from: Jim on 01/03/2022 04:55 pm

Quote from: jmjawors on 01/03/2022 03:54 pm
The efficiency of the Ariane rocket will allow JWST to operate "a lot more than" the initial ten years.

It is initial five years.

The minimum baseline is five years, but both Bill Ochs (35:53 in the briefing) and the blog post (https://blogs.nasa.gov/webb/2021/12/29/nasa-says-webbs-excess-fuel-likely-to-extend-its-lifetime-expectations/) said they have fuel for more than 10 years.

russianhalo117 · « **Reply #41 on:** 01/03/2022 05:49 pm »

Quote from: Lee Jay on 01/03/2022 05:38 pm

Quote from: Jim on 01/03/2022 04:55 pm
Quote from: jmjawors on 01/03/2022 03:54 pm
The efficiency of the Ariane rocket will allow JWST to operate "a lot more than" the initial ten years.

It is initial five years.

The minimum baseline is five years, but both Bill Ochs (35:53 in the briefing) and the blog post (https://blogs.nasa.gov/webb/2021/12/29/nasa-says-webbs-excess-fuel-likely-to-extend-its-lifetime-expectations/) said they have fuel for more than 10 years.

AFAIU, a formal mission extension for years 6 through 10 would be needed.

Lee Jay · « **Reply #42 on:** 01/03/2022 05:55 pm »

Quote from: russianhalo117 on 01/03/2022 05:49 pm

Quote from: Lee Jay on 01/03/2022 05:38 pm
Quote from: Jim on 01/03/2022 04:55 pm
Quote from: jmjawors on 01/03/2022 03:54 pm
The efficiency of the Ariane rocket will allow JWST to operate "a lot more than" the initial ten years.

It is initial five years.

The minimum baseline is five years, but both Bill Ochs (35:53 in the briefing) and the blog post (https://blogs.nasa.gov/webb/2021/12/29/nasa-says-webbs-excess-fuel-likely-to-extend-its-lifetime-expectations/) said they have fuel for more than 10 years.

AFAIU, a formal mission extension for years 6 through 10 would be needed.

Undoubtedly, but there's no way they'd stop using a healthy $10B observatory, so most people consider these mission extensions formalities, assuming the instrument is still viable.

centaurinasa · « **Reply #43 on:** 01/03/2022 06:21 pm »

https://blogs.nasa.gov/webb/2022/01/03/webb-team-moving-forward-with-sunshield-tensioning/

https://twitter.com/NASAWebb/status/1478045927621410823

kessdawg · « **Reply #44 on:** 01/03/2022 06:29 pm »

Please move to the discussion thread

Blackstar · « **Reply #45 on:** 01/03/2022 07:56 pm »

You can follow along at home with the Webb checklist:

https://www.aura-astronomy.org/wp-content/uploads/2022/01/Webb-to-L2-Checklist-revised.pdf

Lee Jay · « **Reply #46 on:** 01/03/2022 09:29 pm »

https://blogs.nasa.gov/webb/2022/01/03/first-layer-of-webbs-sunshield-tightened/

"Today, at 3:48 pm EST, the Webb team finished tensioning the first layer of the observatory’s sunshield– that is, tightening it into its final, completely taut position. "

dsmillman · « **Reply #47 on:** 01/04/2022 12:04 am »

Great Progress:

Second and Third Layers of Sunshield Fully Tightened

The Webb team has completed tensioning for the first three layers of the observatory’s kite-shaped sunshield, 47 feet across and 70 feet long.

The first layer – pulled fully taut into its final configuration – was completed mid-afternoon.

The team began the second layer at 4:09 pm EST today, and the process took 74 minutes. The third layer began at 5:48 pm EST, and the process took 71 minutes. In all, the tensioning process from the first steps this morning until the third layer achieved tension took just over five and a half hours.

These three layers are the ones closest to the Sun. Tensioning of the final two layers is planned for tomorrow.

“The membrane tensioning phase of sunshield deployment is especially challenging because there are complex interactions between the structures, the tensioning mechanisms, the cables and the membranes,” said James Cooper, NASA’s Webb sunshield manager, based at Goddard Space Flight Center. “This was the hardest part to test on the ground, so it feels awesome to have everything go so well today. The Northrop and NASA team is doing great work, and we look forward to tensioning the remaining layers.”

Once fully deployed, the sunshield will protect the telescope from the Sun’s radiation. It will reach a maximum of approximately 383K, approximately 230 degrees F, while keeping the instruments cold at a minimum of approximately 36K or around -394 degrees F.

redliox · « **Reply #48 on:** 01/04/2022 02:13 am »

Encouraging 3 out of 5 layers went off without a hitch (of course it's preferable). Although things seem on a good roll, any worst case scenarios if only 3 or 4 layers work? Is there any calculation on how effective only partial shielding (I will say 3/5 or 4/5 shielding seems pretty darn good [for odds of space-age tin foil not shredding] outside of 5/5) could be is necessary?