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James Webb Space Telescope emerges successfully from final thermal vacuum test

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Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#31

Post by sandyrogers »

maxxxxx wrote: post #12
gjm11 wrote: post #5

Earlier quoted context omitted.

The main imager is the Near Infrared Camera. It has ten 2048x2048 sensors. They're configured in two kinda-independent groups with separate optics. Each group uses one of those sensors for longer wavelengths (so you get two lots of 2048x2048), and four of them for shorter wavelengths (so you get two lots of 4096x4096). The two modules can (and I guess usually will) be pointed at adjacent regions of the sky; I expect…

Considering how much camera sensors have improved in the last few years I wonder how outdated these sensors are (or not) Edit: makes me also wonder if with all the delays they upgrade any equipment in the meantime.

I seem to remember the detector arrays for MIRI were built sometime between 2005 and 2009. (I worked on MIRI for a time in 2011)

Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#32

Post by Klathmon »

knd775 wrote: post #19
NikolaeVarius wrote: post #7

Man, I really want this telescope to succeed its mission, but I just can't get over how complex its deployment procedure is. I am extremely pessimistic about it actually managing to deploy as planned.

And this isn't like hubble, where we could (and did) send up a space shuttle to fix an issue after launch. Really scary.

To be a bit more specific, we can't send something up to fix this because it's magnitudes further away from the earth than Hubble is.

JWT will be ~1.5 million km away from earth, in a special orbit around a spot called the "L2 Lagrange point". It's located there so that it can kind of hide in the earth's shadow at pretty much all times and keep all the nearby "bright" things behind the heat shield.

For comparison, the Hubble is ~600km away from the surface orbiting the Earth, and the Moon is a little under 400,000km away from the earth. JWT will be almost 4x further away than even the moon.

Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#33

Post by icegreentea2 »

java-man wrote: post #27

what puzzles me all the time is why not build two instead. it looks like the R&D portion of the budget might be greater than the actual manufacturing cost, so building two would be less than 2x the price. if one launch fails, we've got a backup. if both launch, we have two instruments deployed. why don't we do it??

The NASA-Congress decision making complex is kind of a monster. Often makes lot of penny wise, pound foolish decisions. (I should say ${X-Body}-Congress decision making complex is like that).

Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#34

Post by skizm »

Anyone know if there are any well paying jobs in space programs of any kind? I've been seeing a growing number of reputable universities offering a wider range of space / aerospace / engineering offerings* and I've been getting curious what's out there. Only issue is, a lot of places I looked pay well below market rates :/ (at least for software engineers). I'll admit my expectations might be off considering I've been in the NYC area for a while now, and am used to seeing NYC salaries, but the pay is well below half of what I would make now and the cut seems too drastic even in a LCOL area.

* I'm mostly talking about masters programs here.

Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#35

Post by mhb »

java-man wrote: post #27

what puzzles me all the time is why not build two instead. it looks like the R&D portion of the budget might be greater than the actual manufacturing cost, so building two would be less than 2x the price. if one launch fails, we've got a backup. if both launch, we have two instruments deployed. why don't we do it??

Is there any economy of scale? Why not wait until the first one fails to build another one?

Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#36

Post by gnu8 »

NikolaeVarius wrote: post #7

Man, I really want this telescope to succeed its mission, but I just can't get over how complex its deployment procedure is. I am extremely pessimistic about it actually managing to deploy as planned.

I have read in other discussions that the contractor has great confidence in the deployment of the sun shield because of their experience with similar systems on classified satellites. I think as long as the launch is successful there won’t be any problems with the mission.

Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#37

Post by jcadam »

skizm wrote: post #34

Anyone know if there are any well paying jobs in space programs of any kind? I've been seeing a growing number of reputable universities offering a wider range of space / aerospace / engineering offerings* and I've been getting curious what's out there. Only issue is, a lot of places I looked pay well below market rates :/ (at least for software engineers). I'll admit my expectations might be off considering I've bee…

Just a bit of warning: Software Engineering in Aerospace is NOT fun. You're basically in a supporting role to the hardware and system engineers designing the spacecraft. It's pure drudgery... process to the point of absurdity, specs and tasks being spoon fed to you with little room for creativity and/or problem solving, etc.

The pay, benefits, and level of respect on the job reflect all of that.

If you really want to work in space, I'd go and get a MS (or higher) in aerospace engineering or space systems engineering and work at the systems level.

I got out of aerospace and am much happier for it.

Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#38

Post by mdorazio »

jcadam wrote: post #37
skizm wrote: post #34

Anyone know if there are any well paying jobs in space programs of any kind? I've been seeing a growing number of reputable universities offering a wider range of space / aerospace / engineering offerings* and I've been getting curious what's out there. Only issue is, a lot of places I looked pay well below market rates :/ (at least for software engineers). I'll admit my expectations might be off considering I've bee…

Just a bit of warning: Software Engineering in Aerospace is NOT fun. You're basically in a supporting role to the hardware and system engineers designing the spacecraft. It's pure drudgery... process to the point of absurdity, specs and tasks being spoon fed to you with little room for creativity and/or problem solving, etc. The pay, benefits, and level of respect on the job reflect all of that. If you really want to…

To be fair, the reason for this is that if you try to be creative and don't follow strict processes, things fail a million miles from Earth or blow up entirely.

Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#39

Post by escapecharacter »

Klathmon wrote: post #32
knd775 wrote: post #19

Earlier quoted context omitted.

And this isn't like hubble, where we could (and did) send up a space shuttle to fix an issue after launch. Really scary.

To be a bit more specific, we can't send something up to fix this because it's magnitudes further away from the earth than Hubble is. JWT will be ~1.5 million km away from earth, in a special orbit around a spot called the "L2 Lagrange point". It's located there so that it can kind of hide in the earth's shadow at pretty much all times and keep all the nearby "bright" things behind the heat shield. For comparison, th…

I mean, the giddy idiot in me just gets excited about the urgent need for a human L2 mission to fix it.

Re: James Webb Space Telescope emerges successfully from final thermal vacuum test

#40

Post by [deleted] »

skizm wrote: post #34

Anyone know if there are any well paying jobs in space programs of any kind? I've been seeing a growing number of reputable universities offering a wider range of space / aerospace / engineering offerings* and I've been getting curious what's out there. Only issue is, a lot of places I looked pay well below market rates :/ (at least for software engineers). I'll admit my expectations might be off considering I've bee…

[deleted]
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