The Webb Telescope

https://www.npr.org/2021/12/17/1064724045/this-new-space-telescope-should-reveal-what-the-universe-looked-like-as-a-baby?utm_source=pocket-newtab

@jimm619
Launch Christmas Eve, 10 billion on the line. A LOT of stuff has to work perfectly to pull this off. Of course NASA did a bangup job of getting rovers to Mars safely so fingers crossed.

They said the mirrors are so subtle in shape they are pretty useless as a telescope mirror until the temperature of the mirror goes down near 400 degrees below zero F and the sun shield takes 200,000 watts coming from the sun and 20 MILLIWATTS gets through, quite a shield.

Just looking at this James Webb Space Telescope makes me nervous. It looks totally and permanently exposed to any micrometeorite or dust particle that might slam into it.
In addition, how sure are they that Lagrange point L2, where this scope will sit, is not packed full of space rocks or pebbles? Lagrange points tend to collect all sorts of space junk.

@bunnyknight
They would not have planned to put it there if they didn't have safety data and they do because we already have probes in Lagrangians, just not that one.

@bunnyknight said
Just looking at this James Webb Space Telescope makes me nervous. It looks totally and permanently exposed to any micrometeorite or dust particle that might slam into it.
In addition, how sure are they that Lagrange point L2, where this scope will sit, is not packed full of space rocks or pebbles? Lagrange points tend to collect all sorts of space junk.

@jimm619
Stuff even in Earth orbit does not get whacked by debris very much, I think you can count the number of hits on one hand in the past 30 years.

And out a mil and a half from home there will still be debris, dust, meteors, asteroids, comets, solar winds, solar storms so it is not exactly a benign place to live but like our Hubble scope has not been hit by anything and it has been up for decades.

@sonhouse
I just hope they have spare parts to repair any potential damage. Imagine if a tiny sand grain damaged that huge exposed mirror with no way to fix it. Scary.

@bunnyknight said
@sonhouse
I just hope they have spare parts to repair any potential damage. Imagine if a tiny sand grain damaged that huge exposed mirror with no way to fix it. Scary.

I surely hope all goes well with the Webb.
I cannot wait for all the new discoveries to come pouring in. There should be some awesome imaging.
I regularly visit Astronomy.com and get Astronomy Magazine. We are embarking on a new era of discovery.

Quite the recess from my country's totally divided, politically motivated narratives that pass for "news" these days.

Peace to all! And for those who don't find it offensive, Merry Christmas.

@venda
There is redundancy onboard both Hubble and Webb so in that sense they can be repaired remotely.

No more flights to Hubble though and Webb will be a mil and a half away so no humans will see THAT probe for decades or more, where some automatic repair probe could work on it.

Hubble just had two downtimes that were worked out by remote control and it is back in business now.

@venda said
The hubble telescope can't be "repaired" anymore since the space shuttles were de commisioned.
I don't know if they have a strategy for the James Webb

@jimm619
That is what redundancy is for. The ALWAYS put in redundant circuits so if one poops out, they can switch it via radio.

@sonhouse said
@jimm619
That is what redundancy is for. The ALWAYS put in redundant circuits so if one poops out, they can switch it via radio.

@jimm619 said
HUBBLE-------9 ft, mirror
WEBB---------14 ft, mirror

@bunnyknight said
Just looking at this James Webb Space Telescope makes me nervous. It looks totally and permanently exposed to any micrometeorite or dust particle that might slam into it.
In addition, how sure are they that Lagrange point L2, where this scope will sit, is not packed full of space rocks or pebbles? Lagrange points tend to collect all sorts of space junk.