Space Junk — anything and everything related to astronomy

It has now apparently found its guide star...
https://www.space.com/james-webb-space-telescope-locks-first-star

If you scroll down a bit "Step 2 Segment Alignment" is shown as "Most recently completed" so they're ahead of schedule.
Next step is "image stacking" https://jwst.nasa.gov/content/webbLaunch/deploymentExplorer.html#34
I have done this — all my old photos are stacked in boxes somewhere

The "cold side" numbers are all less than 45K, but the instruments are still a wee bit warm

https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html?units=metric <

The process of aligning the scope in detail:
https://blogs.nasa.gov/webb/2022/02/03/photons-incoming-webb-team-begins-aligning-the-telescope/

Image stacking complete
https://blogs.nasa.gov/webb/2022/02/25/webb-mirror-alignment-continues-successfully/

It looks nice for sure.

Almost all the measurement points are now below the cutoff of 45K, but there is still a lot of alignment work to be completed before it is ready to go to work

Okay. Hopefully this will be a succes.

the timeline shows that Coarse phasing is done, but the counters still shows phase 4.
I hope nothing is wrong
https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html?units=metric <

Originally posted by VorpalF2F
I hope nothing is wrong
https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html?units=metric

Apparently nothing wrong — there is now an explanation paragraph:

from
https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html?units=metric <
Status: Ongoing - Interleaved with Step 5

Although Image Stacking puts all the light in one place on the detector, the segments are still acting as 18 small telescopes rather than one big one. The segments need to be lined up with each other with an accuracy smaller than the wavelength of the light.

Conducted three times during the commissioning process, Coarse Phasing measures and corrects the vertical displacement (piston difference) of the mirror segments. Using a technology known as Dispersed Fringe Sensing, we use NIRCam to capture light spectra from 20 separate pairings of mirror segments. The spectrum will resemble a barber pole pattern with a slope (or angle) determined by the piston difference of the two segments in the pairing.

https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html?units=metric

Now showing stage 5 — fine phasing.
I didn't even know that had invented phasers yet

The main link is showing Stage 5 completed — now on Stage 6
See: https://www.nasa.gov/press-release/nasa-s-webb-reaches-alignment-milestone-optics-working-successfully

and
https://www.space.com/james-webb-space-telescope-alignment-photo

Nice to see it's going well with the James Webb space telescope.

Stage 6 now...
https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html?units=metric

Still one point that is well above operating temperature...

I see. Hopefully we get nice foto's soon, but time will tell.

Too complicated. When will it give us pics?

Originally posted by Kyyberi
Too complicated. When will it give us pics?
June or July — there have already been a few test shots

actually...
first real image shows at 0:53

Unless you're keen you can stop the video after a couple of minutes, since no JWST images past that point.
A lot of discussion of new launch technology from that point on.

Also of interest:

This one can't be embedded in a post — I presume because of the "/shorts/" in the URL
https://www.youtube.com/shorts/385JLByRtVE

Not to bad. Patience is key here, but waiting for 3 months is long.

Originally posted by SDK1987
Not to bad. Patience is key here, but waiting for 3 months is long.

probably planned that way — one instrument on the "cold" side is still above 44K, and apparently they need to be colder than that to work effectively

I expect they have tested this as well. It's tough to get a environment of 44K