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I need to know about the data, which scientist have already received from JWST about the CMB.

Jahid Hossain
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    JWST doesn't observe in the microwave range... – Sten Sep 25 '23 at 06:39
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    @Sten But couldn’t this information be obtained indirectly using his measuring instruments? – dtn Sep 25 '23 at 07:01
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    @dtn something like measuring heating of gas by the CMB? – Sten Sep 25 '23 at 07:32
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    @Sten or something like a microwave radiometer with Horn antennas, like here. True, I don’t know if there is similar equipment at JWST. Or calculating microwave background parameters from other measured data using mathematical models. – dtn Sep 25 '23 at 08:10
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    Here you have all the data: https://archive.stsci.edu/missions-and-data/jwst – planetmaker Sep 25 '23 at 08:58
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    @planetmaker and all these cameras, instruments, spectrographs, are they some kind of unique instruments that were developed specifically for this telescope or are they some kind of “mass” instruments, from which we can simply choose the ones we like? – dtn Sep 25 '23 at 09:07
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    @dtn I don't understand your question or how it is related to the topic of this question. You can use all the data however you like, and the instrument design and calibration is also available so everyone can derive meaningful conclusions from them. How does the process of instrument design matter here? (hint: of course it has unique instruments - but not that unique that their principles are unique). – planetmaker Sep 25 '23 at 10:33
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    Can you be clearer about what effects the JWST might be sensitive to, or change your question so it is clearly asking IF (and how) there is anything that JWST can learn about the CMB? – ProfRob Sep 25 '23 at 10:40
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    @planetmaker My question is not directly related to the topicstarter question. He can help make clarification. My question was about: how the set of instruments of the telescope being created is determined. If, for example, a camera is needed, is it also created from scratch for a specific telescope or is it selected from existing models? Does the mission include the ability to measure previously unforeseen parameters (as in the case of the CMB)? – dtn Sep 25 '23 at 11:08
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    @dtn That's not really a discussion to have in the comments of somebody else's question, but if you want to post your own question, feel free. – Darth Pseudonym Sep 25 '23 at 13:03
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    @DarthPseudonym and where is it better to ask this question: Astronomy, Physics or Space Exploration Stack Exchange? – dtn Sep 25 '23 at 14:40
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    @dtn whatever fits - depends on your exact question; astronomy might be suitable. But as you might know, SE works strictly on a basis of one question, only answer way - and comments are only for clarifications regarding the question and not extended off-topic discussions. – planetmaker Sep 25 '23 at 15:05
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    @planetmaker https://astronomy.stackexchange.com/questions/54845/formation-of-spacecraft-instrumentation – dtn Sep 26 '23 at 09:23
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    @DarthPseudonym https://astronomy.stackexchange.com/questions/54845/formation-of-spacecraft-instrumentation – dtn Sep 26 '23 at 09:24

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The James Webb Space Telescope is very specifically built to look at infrared light, not microwaves, so it hasn't collected information about the Cosmic Microwave Background directly. However, you might have recently heard about JWST and CMB in the same discussion because JWST has been observing Cepheid variable stars, which are related to CMB in an indirect sort of way.

The ongoing so-called "crisis in cosmology" is that there are two ways to measure the expansion of the universe: one by examining the CMB, and the other by observation of supernovas, using Cepheid variables to determine distance calibrations. The "crisis" is that the two measurements' error bars have shrunk to the point that they no longer overlap: there is no value that could fit both measurements. We have two ways to measure expansion, and they fundamentally disagree on the answer.

JWST recently did some work to see if the Cepheid distance values were being biased by other nearby stars interfering with our brightness measurements (which was one theory of why we might be seeing this divergence), but the result was that no, we actually had done a good job of adjusting for that and our distance measurements seem to be working correctly -- so the "crisis" continues.

Footnote: I dislike the term "crisis" because it implies that there's an emergency, that our whole understanding of the universe and physics itself is in danger of collapse -- which is of course absurd. As it's said, scientific progress very rarely sounds like "Eureka! I have found it!"; instead it usually sounds like "Huh. That's weird..." The fact that we have two measurements that disagree is not a terrible thing (however frustrating it might be for the theorists), because it's a signpost that shows us that there's something we should study right over there.

Darth Pseudonym
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