Updates James Webb Space Telescope updates

Ripley

Tutorial translator
Donator
Joined
Sep 12, 2010
Messages
3,133
Reaction score
407
Points
123
Location
Rome
Website
www.tuttovola.org
I've just noticed that NASA's "eyes on the solar sytem" website still shows a closed/undeployed WEBB...
 

Thunder Chicken

Fine Threads since 2008
Donator
Joined
Mar 22, 2008
Messages
4,327
Reaction score
3,246
Points
138
Location
Massachusetts
Need to coarse tune all 18 mirror. This will start any moment and continue next 2 weeks.
Then L2 insert burn.
Than 3 month fine mirror alignment and instrument calibration.
Why do the optics tuning and alignments take so long? I understand that the telescope has to chill and reach thermal equilibrium to avoid thermal distortion, but my back of the envelope heat transfer calculations suggest that should take days to a few weeks, not months. Maybe they are looking for "more 9s" closer to equilibrium before doing the fine alignments and taking first data? Shedding the last few degrees will be a slow process.
 

TheShuttleExperience

Well-known member
Joined
Feb 24, 2021
Messages
918
Reaction score
1,194
Points
108
Location
Earth
@Soumya-8974 and @N_Molson indeed. We are entering a new era for sure. And Artemis is just one amazing part of it, next to JWST. If we work together, we can truly achieve some amazing stuff. The word "impossible" will most likely become more and more meaningless in the future ?
 

JDat

Active member
Joined
Sep 6, 2010
Messages
105
Reaction score
74
Points
43
Why do the optics tuning and alignments take so long? I understand that the telescope has to chill and reach thermal equilibrium to avoid thermal distortion, but my back of the envelope heat transfer calculations suggest that should take days to a few weeks, not months. Maybe they are looking for "more 9s" closer to equilibrium before doing the fine alignments and taking first data? Shedding the last few degrees will be a slow process.

From my knowledge how it works:
18 mirror segments on main mirror and 1 segment(?) on secondary mirror
Each segment on main mirror have 6 servos on corners + 1 servo to change shape/bending for segment.
Secondary mirror have 6 servos/

Calibration process ( program in GWBASIC ):
10) Coll down sensors
20) Point JWST to "calibration star".
30) Take photo.
40) Download image.
50) Analyse.
60) Send tuning commands to servo.
70) Repeat (goto 20) until all segments aligned.
80) L2 insert burn
90) More sensor chilling
100) Imaging (detector) Sensor test and calibration
110) More mirror aligment.

Couterquestion: why origami deployment took 2 weeks? You can activate all deployment mechanisms and do it in 16 hours...

;)
 

GLS

Well-known member
Orbiter Contributor
Addon Developer
Joined
Mar 22, 2008
Messages
5,870
Reaction score
2,867
Points
188
Website
github.com
Couterquestion: why origami deployment took 2 weeks? You can activate all deployment mechanisms and do it in 16 hours...
My guesses are: (1) DSN time, (2) available power several motors at once, and probably the big one is (3) making sure the previous step was well performed and things are ok before continuing.
Anyway, there's no rush as it will take a long time for the telescope to cool to it's operating temperature.
 

Sbb1413

Well-known member
Joined
Aug 14, 2018
Messages
948
Reaction score
373
Points
78
Location
India
Preferred Pronouns
he/his/him
Updated my wall collage with the inclusion of another Falcon 9 rocket (carrying a batch of Starlinks) and one of the early images taken by JWST. My wall collage is growing quite rapidly and will likely include Saturn V in 2024, at the 55th anniversary of Apollo 11.
IMG_20220215_100357.jpg
Anyway, glad to see the telescope is working as planned.
 

N_Molson

Addon Developer
Addon Developer
Donator
Joined
Mar 5, 2010
Messages
9,271
Reaction score
3,244
Points
203
Location
Toulouse
You definitively should include a R-7/Soyuz rocket, its something iconic.
 
Top