28
$\begingroup$

The James Webb Space Telescope has a complicated deployment sequence. Beyond data from sensors aboard the spacecraft, does it have any cameras to take pictures of the process?

$\endgroup$
2
20
$\begingroup$

As of now, it does not and that's not likely to change. I asked this question of leaders of the JWST project at Goddard Space Flight Center. It isn't that it wouldn't be useful, the problem is funds and time. Considering the current cost of the project, any new addition would increase the cost and could impact the scheduled launch date of October 2018.

The camera would need to work in a vacuum. Is MLI (multi-layer insulation) sufficient to keep it's temperature in its operating range? How and where would you mount it? Would you need to supply artificial lighting? Where would you find the bandwidth to send the images back? Resolving these issues would require resources that are in extremely short supply now.

$\endgroup$
6
  • 3
    $\begingroup$ None of that is new technology. Shuttle and station all had/have external cameras. Agree that it's a "nice to have" though, not a mission requirement. Unless, of course, something goes wrong with the deployment. $\endgroup$ Oct 20 '16 at 23:25
  • 3
    $\begingroup$ @OrganicMarble Sentinel-1's solar panel deployment camera was activated and brought on-line following an unexplained power anomaly and discovered this little beauty! But for JWST with all those moving parts, not sure where a camera could actually be put and additional cabling could be added without a risk/benefit engineering review. $\endgroup$
    – uhoh
    Jan 24 '17 at 5:40
  • $\begingroup$ A camera especially with an additional light source migth also put the actual assignment of the JWST at risk as it requires to be extremely cold. So cold that it even has its own heat shield as it will look deep into the infrared range. Any additional equipment would need to be thorougly checked to not compromise the primary mission. $\endgroup$
    – Adwaenyth
    Jan 24 '17 at 8:20
  • 1
    $\begingroup$ This is like software without tests, because we don't have time and money for the tests. $\endgroup$
    – Qian Chen
    Dec 29 '21 at 10:45
  • 3
    $\begingroup$ @QianChen, no, it's software with loads of tests and diagnostics, but without a visual debugger. $\endgroup$
    – Sz.
    Jan 2 at 10:48
7
$\begingroup$

NASA published an extensive answer to this question on their blog today. Some key points as to why no cameras were added:

  • You wouldn't actually be able to see anything useful: a wide-angle camera would not provide enough detail, and you would need so many narrow-angle to get enough details for them to be useful, that it would be too complex to be worth the effort.
  • Wiring harnesses would have to be routed across already complex structures that unfold and move during deployment.
  • The cameras would need to be able to work in either cryogenic temperatures (when on the cold side), or be encapsulated. They could become a noise source.

They actually did investigate adding cameras, but found it not worthwhile:

Notwithstanding these challenges, engineers mocked up and tested some camera schemes on full-scale mockups of Webb hardware. However, they found that deployment surveillance cameras would not add significant information of value for engineering teams commanding the spacecraft from the ground.

$\endgroup$
4
$\begingroup$

mentions several reasons for not having a camera:

  • would need several cameras at several locations
  • would need artificial light
  • should be constructed from scratch to resist the low temperature on the dark side
  • In case of failures could create unwanted debris
  • keep load to a minimum
$\endgroup$
3
  • $\begingroup$ Please provide some time stamp in the answer. The linker video is too long! $\endgroup$ Jan 5 at 18:24
  • $\begingroup$ @karthikeyan already done, YouTube link has timestamp $\endgroup$ Jan 5 at 20:50
  • $\begingroup$ Imho it boils down to that the JWST project was a project management disaster and they had no other choice than gambling a lot at the end. So they decided to gamble, and they did everything to maximize the chances, but the essence of the project is still a big gambling. It seems, they won (the most dangerous things are already behind). $\endgroup$
    – peterh
    Jan 11 at 22:51

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.