James Webb Telescope Launch (finally)

www.jwst.nasa.gov

Where Is Webb? NASA/Webb

During Webb's launch, deployment and commissioning, 'WhereIsWebb' tracked Webb's 'flight' to L2 orbit, its state and progress during its deployment and commissioning process, and finally the release of its first images. This process is now complete. During this process, the page constantly...
www.jwst.nasa.gov

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Things are going to be strangely boring now after all that nervous activity.

A few days of coarse adjustments to the primary mirrors, moving from launch safety positions to usage positions.

Next more or less is the last burn to achieve orbit, surprisingly flexible in scheduling and expected to be uneventful.

Then their slower-than-grass-grows fine tuning of the primary mirrors, along with the secondary mirror on the tripod. (The internal 3rd (tertiary) mirror is left unadjusted.)
The fine tuning steps are as small as about 1/20 000th the width of a human hair.
This goes on for about 3 months, some of it dependent on the one science instrument first getting cold enough for alignment related use.

Then about 2 months of further cooling and instruments calibration.

Only after that will the pics start rolling in... worth the wait.

And one of the NASA seniors opened their mouth this weekend - turns out the extra fuel saved is even more than expected.. allowing for up to double the lifetime period, in other words 20 years of use is now possible!!
(Subject to many possible altering events.)
 
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RiaX said:
Where are the fancy pictures :( ?
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If you mean pictures of the deployment, all of that happened in the dark! The whole point of the sunshade was to allow the instruments to cool down to -200C, so that heat from the mirror itself does not affect the infrared observations. NASA did show a complex 3D CGI animation of the process.
 
I hate to ask this, but with Hubble, almost as soon as it launched there were issues, and they had to send a Shuttle mission to fix them.

with this, if there were issues, what then? I mean did they have a backup plan?
and what would it have entailed?
 
The novelty and joy of this sort of thing is never lost on me. I feel privileged to be alive at time like this. And the first pictures, no matter what they are, will be another exciting moment. Go James Webb!
 
Gordon_R said:
If you mean pictures of the deployment, all of that happened in the dark! The whole point of the sunshade was to allow the instruments to cool down to -200C, so that heat from the mirror itself does not affect the infrared observations. NASA did show a complex 3D CGI animation of the process.
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No I want the rendered images of what it sees
 
eg2505 said:
I hate to ask this, but with Hubble, almost as soon as it launched there were issues, and they had to send a Shuttle mission to fix them.

with this, if there were issues, what then? I mean did they have a backup plan?
and what would it have entailed?
Click to expand...
Very different beast, unfortunately - Hubble was in orbit 570km from earth, Webb is at l2 Lagrange point, 1.5 million kms away. That's way beyond the orbit of the moon, and it would be by far the furthest away we have ever sent a manned mission.

464173main_L2_Webb_rework.jpg
 
RiaX said:
No I want the rendered images of what it sees
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This isn't a GoPro, can't expect instant results... /s

It is a mistake to think of astronomy as taking pictures. That era peaked in the mid 20th century. Recent telescopes show improvements in sharpness and light-gathering, but most research since then has been spectroscopy. Pretty images are a mostly a by-product for PR reasons.
 
eg2505 said:
I hate to ask this, but with Hubble, almost as soon as it launched there were issues, and they had to send a Shuttle mission to fix them.

with this, if there were issues, what then? I mean did they have a backup plan?
and what would it have entailed?
Click to expand...
NASA themselves admit it was a gamble, but a very carefully planned one. They were anal about details, testing and whatever backup was possible with just about everything.

Personally I still think we were lucky, Murphy isn't usually so kind.
 
eg2505 said:
I hate to ask this, but with Hubble, almost as soon as it launched there were issues, and they had to send a Shuttle mission to fix them.

with this, if there were issues, what then? I mean did they have a backup plan?
and what would it have entailed?
Click to expand...

Hubble was launched with 3 planned Shuttle servicing missions already in mind. With Webb there was never a plan B, so the design was tested much more carefully.
 
eg2505 said:
I hate to ask this, but with Hubble, almost as soon as it launched there were issues, and they had to send a Shuttle mission to fix them.

with this, if there were issues, what then? I mean did they have a backup plan?
and what would it have entailed?
Click to expand...
If something goes wrong and it cannot be fixed via software then thats it. It becomes space junk, it cannot be repaired by hand
 
Brian_G said:
Sort of, we're past the point of most major failure concerns now in their opinion.
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but is it still possible some line of code in the systems that control the Mirror for instance fail?
I mean its not unheard of for a single apostrophe to break the entire billion dollar spacecraft. it has happened before, correct?

what then? can they re-flash and replace the entire O/S of the Telescope from the ground?
 
Enzo Matrix said:
If something goes wrong and it cannot be fixed via software then thats it. It becomes space junk, it cannot be repaired by hand
Click to expand...
but they do have thrusters correct? cant they steer it closer to Earth for repairs?
or does it not have fuel for that?

hence my question for an automated robot that could conceivably be sent out to repair it.
does such a backup plan exist?
 
jwst.nasa.gov

Webb FAQs - NASA Science

The James Webb Space Telescope, also called Webb or JWST, is a large, space-based observatory, optimized for infrared wavelengths, which complements and
jwst.nasa.gov jwst.nasa.gov

Look ar point nr28. No manual servicing is possible. Its simply too far away
 
eg2505 said:
but is it still possible some line of code in the systems that control the Mirror for instance fail?
I mean its not unheard of for a single apostrophe to break the entire billion dollar spacecraft. it has happened before, correct?

what then? can they re-flash and replace the entire O/S of the Telescope from the ground?
Click to expand...
Absolutely a danger, sure.
What I've seen them doing so far in their live broadcasts of deployments is pause for every line of code which is actually created here according to a script, examine it by at least one other, approve it, and then the on-board computer asks for it to still be confirmed.
As I said, anal.

eg2505 said:
but they do have thrusters correct? cant they steer it closer to Earth for repairs?
or does it not have fuel for that?

hence my question for an automated robot that could conceivably be sent out to repair it.
does such a backup plan exist?
Click to expand...
No round trip is / was possible as it's too complex and limiting for that distance.
As for a robot, still too far in the future for any kind of such normal service. It would be a separate mission of its own and both expensive and useless if not needed.
 
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