Tracking the James Webb Telescope

[sjastro]

I've been looking for that since I lost it years ago! Be a mate and mail it to me please.

Alas an object not much larger than a dust mote was destined to be lost only an image remains.

 

[Aldebaran]

Tracking the 10 billion dollar James Webb Space Telescope

December 25th - Liftoff
Deployed- spacecraft appendages (solar arrays, high gain antenna)
Working on - Unfolding sunshield
Hoping - Tower and mirrors deploy correctly

A lot can go wrong! Live from the James Webb site...

Where Is Webb? NASA/Webb

Yes, there is a lot that can go wrong, so I'd love to know why they're placing it 4x further from the earth than the moon. The Hubble telescope is in earth's orbit, which allowed it to be serviced when parts wore out, or anything else went wrong (like it did at the very beginning for Hubble). But the James Webb Telescope has no chance to be serviced. Something stops working, and it's done!
I just hope it works for many years before that happens.

 

[sjastro]

Maybe it split upon impact?

Also how did you find an object that small?

It's possible it split on impact or caused by corrosion.

I used a rare earth magnet attached to an old golf putter, it was like separating iron filings from a magnet.

 

[sjastro]

Yes, there is a lot that can go wrong, so I'd love to know why they're placing it 4x further from the earth than the moon. The Hubble telescope is in earth's orbit, which allowed it to be serviced when parts wore out, or anything else went wrong (like it did at the very beginning for Hubble). But the James Webb Telescope has no chance to be serviced. Something stops working, and it's done!
I just hope it works for many years before that happens.

The James Webb Space Telescope will be located at the second Lagrange point or L2.
At L2 the telescope stays in line with the Earth as it orbits around the Sun.
This will allow the satellite's large sunshield to protect the telescope from the light and heat of the Sun and Earth (and Moon).

 

[FrumiousBandersnatch]

Interesting medical spin-off of the JWST mirror technology: Telescope Innovations Improve Speed, Accuracy of Eye Surgery.

 

[Ophiolite]

What NASA is talking about is micrometeoroid impacts...

Yes, I understand that. And I understand that they were aware of the issue before they even began designing the telescope. I also understand that, to the extent practical, they incorporated mitigating features into the design.

What pains me the most is the understanding that the popular media distort these facts to create the impression that NASA have just realised that the telescope may be struck by a meteor (not micrometeor) imminently. And then some wonder why many have, or are developing, an anti-science viewpoint.

 

[FrumiousBandersnatch]

What pains me the most is the understanding that the popular media distort these facts to create the impression that NASA have just realised that the telescope may be struck by a meteor (not micrometeor) imminently. And then some wonder why many have, or are developing, an anti-science viewpoint.

Yes; they do it as click-bait, without a care for the consequences.

 

[rockytopva]

Just in from the @NASAWebb team: "All 18 primary mirror segments and the secondary mirror are now fully deployed!" NASA Administrator Bill Nelson wrote in a tweet posted on Wednesday (Jan. 19). "Congratulations to the teams that have been working tirelessly since launch to get to this point. Soon, Webb will arrive at its new home, L2!"

JWST's golden primary mirror includes 18 individual hexagonal segments, each controlled by seven actuators that allow precise movements. All 18 segments are now in their deployed positions several days sooner than scheduled.

Where Is Webb? NASA/Webb

 

[rockytopva]

With mirrors now fully deployed, Webb is now gearing up for its next crucial step: A crucial burn to insert it into the L2 orbit, currently set for Monday, January 24...

Where Is Webb? NASA/Webb

 

[Aldebaran]

With mirrors now fully deployed, Webb is now gearing up for its next crucial step: A crucial burn to insert it into the L2 orbit, currently set for Monday, January 24...

Where Is Webb? NASA/Webb

I wonder what was the point of deploying the mirrors before it reached its destination. Seems like they'd be more exposed to risk being deployed while traveling a mile per second.

 

[rockytopva]

Hopefully our scientists won't get overly distracted while calculating the L2 insertion point...

 

[FrumiousBandersnatch]

I wonder what was the point of deploying the mirrors before it reached its destination. Seems like they'd be more exposed to risk being deployed while traveling a mile per second.

Not really; JWST will still be travelling at high velocity relative to potential impactors when it orbits L2 and it will be there up to 20 years, so a week or two on the way is not an issue.

They may also have thought it better to deploy the major hardware elements before JWST was too far out, so that in case of problems, the stronger signal and shorter signal delay would make attempts to diagnose and rectify them easier (speculating here!).

 

[Hans Blaster]

Not really; JWST will still be travelling at high velocity relative to potential impactors when it orbits L2 and it will be there up to 20 years, so a week or two on the way is not an issue.

They may also have thought it better to deploy the major hardware elements before JWST was too far out, so that in case of problems, the stronger signal and shorter signal delay would make attempts to diagnose and rectify them easier (speculating here!).

The reflective surfaces have been pointing outward into space facing possible incoming micro-meteors since the shroud was ejected about 1 hour after lift off.

The "deployment" of the mirrors just completed moved them about one-half inch to get them free of the pegs that kept them from rattling during launch. Now they will conduct 3 (or so) months of fine focusing by moving the mirrors tiny amounts.

 

[The IbanezerScrooge]

L2 insertion point reached! Just now!

Cruising speed a cosmic turtle's pace at 452 mph

 

[rockytopva]

L2 insertion point reached! Just now!

Cruising speed a cosmic turtle's pace at 452 mph

Looks like we are one hour from the news… https://www.jwst.nasa.gov/content/webbLaunch/whereIsWebb.html

 

[The IbanezerScrooge]

Looks like we are one hour from the news… https://www.jwst.nasa.gov/content/webbLaunch/whereIsWebb.html

Cool! I flipped over to the website just as the miles were ticking down to 0 and distance traveled was reaching 100%

 

[Aldebaran]

Looks like we are one hour from the news… Where Is Webb? NASA/Webb

The wait is hardly over though. News sources say it won't be until May 24th before we see the first images.

 

[rockytopva]

Article begins… Spacecraft controllers have begun powering up the four cutting-edge instruments on NASA's James Webb Space Telescope as they prepare for the observatory's first glimpses of a target star.

That star, called HD 84406, is located 241 light-years from Earth and part of the constellation Ursa Major, the Great Bear. The images will not be used for science, but will help the ground teams align the 18 golden segments of Webb's 21-foot-wide (6.5 meters) main mirror. The images will be taken by Webb's Near Infrared Camera (NIRCam), which first has to cool down to its operational temperature of minus 244 degrees Fahrenheit (minus 153 degrees Celsius).

NASA's James Webb Space Telescope turns on cameras to look at first star target

 

[Aldebaran]

Article begins… Spacecraft controllers have begun powering up the four cutting-edge instruments on NASA's James Webb Space Telescope as they prepare for the observatory's first glimpses of a target star.

That star, called HD 84406, is located 241 light-years from Earth and part of the constellation Ursa Major, the Great Bear. The images will not be used for science, but will help the ground teams align the 18 golden segments of Webb's 21-foot-wide (6.5 meters) main mirror. The images will be taken by Webb's Near Infrared Camera (NIRCam), which first has to cool down to its operational temperature of minus 244 degrees Fahrenheit (minus 153 degrees Celsius).

NASA's James Webb Space Telescope turns on cameras to look at first star target

21 foot mirror. That's 52" bigger than the mirror of the scope on Mt. Palomar, and this is a space telescope!
The views will be incredible!

 

[sjastro]

Sabine gives some technical information behind the JWST mission.