First exposed, then shaded by sunshield, no change in displayed temperature, how can this be correct?

As soon as I posted, they updated the temps. I have watched this for days before this and no change.

  • 3
    $\begingroup$ You should supply more detail, such as where you obtained the data, so others can answer. At the moment we have no confirmation that you have accessed the correct data and that it shows what you suggest. $\endgroup$ Jan 1 at 18:05
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    $\begingroup$ It took me two minutes to find a screenshot of the JWST "Where is Webb" page from December 30th. As of this writing, the Cool side is 40°C colder than the temps shown at universetoday.com/153855/… $\endgroup$
    – notovny
    Jan 1 at 18:37

1 Answer 1


https://www.jwst.nasa.gov/content/webbLaunch/deploymentExplorer.html The sun shield deployment is a multi-day process that started on day three, when the sunshield pallets were opened.

The op is referring to day six when the sunshield left and right sunshield boom's were deployed.

Day 7 and 8 are sunshield layer tensioning, at which point the sunshield is fully deployed; sunshield layer tensioning has been delayed to days 9 and 10.

At each of these steps, the mirrors and the shaded side of JWST cool down. Even when the sunshield is fully deployed, it will take some time (week or two??) for the JWST primary mirrors to cool to the eventual goal, which I think is 30-40 degrees Kelvin. And I think they only update the temperatures daily at https://www.jwst.nasa.gov/content/webbLaunch/whereIsWebb.html


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