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What is Webb observing now?

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Re: What is Webb observing now?

#51

Post by asdff »

basil-rash wrote: post #46
ianburrell wrote: post #45

Earlier quoted context omitted.

Webb won't ever provide a recent view since the images belong to the research group and are only made public when the results are released. Also, Webb can't provide a video feed since it is taking long exposures, and probably only sends results back to Earth when image is finished. The images are in the infrared and only look good when processed.

> only look good when processed Ehh. I personally can’t stand all the post processing folks love to make their results look “magazine ready”. I think the most minimal transformation possible to map the data into 0xRRGGBB would look the best, ideally with a simple standardized algorithm that doesn’t allow for any “artistic license”.

It would be nice if they stopped with the false color, and just scaled it to whatever color an astrounaut might see from that point of view.

Re: What is Webb observing now?

#52

Post by BurningFrog »

basil-rash wrote: post #46
ianburrell wrote: post #45

Earlier quoted context omitted.

Webb won't ever provide a recent view since the images belong to the research group and are only made public when the results are released. Also, Webb can't provide a video feed since it is taking long exposures, and probably only sends results back to Earth when image is finished. The images are in the infrared and only look good when processed.

> only look good when processed Ehh. I personally can’t stand all the post processing folks love to make their results look “magazine ready”. I think the most minimal transformation possible to map the data into 0xRRGGBB would look the best, ideally with a simple standardized algorithm that doesn’t allow for any “artistic license”.

Everything Webb sees is infrared light, which is invisible to humans, so you have to do some processing to make them look good.

Re: What is Webb observing now?

#53

Post by anamexis »

asdff wrote: post #51
basil-rash wrote: post #46

Earlier quoted context omitted.

> only look good when processed Ehh. I personally can’t stand all the post processing folks love to make their results look “magazine ready”. I think the most minimal transformation possible to map the data into 0xRRGGBB would look the best, ideally with a simple standardized algorithm that doesn’t allow for any “artistic license”.

It would be nice if they stopped with the false color, and just scaled it to whatever color an astrounaut might see from that point of view.

Given that these images are infrared, that wouldn't be much.

Re: What is Webb observing now?

#54

Post by asdff »

Cthulhu_ wrote: post #17
jazzsouff wrote: post #14

Earlier quoted context omitted.

The post WW2 cold war is what pushed our understanding of space. So actually modern politics helped with that.

But once the space race to the moon was won - and all major powers had proven they are capable of producing ICBMs - it feels like the energy and financing just went out of it. There's no more political or military gain to be had from space exploration so governments only put in a token amount, and there's only limited commercial gain from e.g. telecom, mapping and navigation, but that's all focused on earth itself. T…

It didn't end just at the ICBM of course or even the nuclear submarine. Satellite warfare became and is still a huge focus. Of course the public was pitched the maintenance bay of the space shuttle was to repair a peaceful satellite only. However, you can imagine how supremely useful it would be for a modern military to have the capability of deploying sappers and a workshop on any object in earth's orbit as well, which is what the space shuttle system also allowed for.

Re: What is Webb observing now?

#55

Post by bobbob1921 »

RajT88 wrote: post #36
syadegari wrote: post #12

+1!! This may sound weird, but I can use this as a mood booster when life gets tough. Side note: I might be biased because I also find it useful to think about the vastness space to trick my brain falling asleep (I watch a lot of video astronomy videos).

“Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.” Per wikipedia: The observable universe contains as many as an estimated 2 trillion galaxies and, overall, as many as an estimated 10^24 stars – more stars (and earth-like planets) than all the grains of beach sand on planet Earth.…

I have always found the analogy all the grains of sand on the beaches of earth to be something that helps accurately convey large numbers to myself and others. Somethings I’ve always wondered about this analogy:

1 – at what depth are they referring to, i.e. if you’re at a beach and dig down two feet you’re still Coming in contact with sand (and grains of sand). Do these count also?

2 – if you wade out into the ocean and go underwater, there are also more grains of sand under the water (are these included?). (what about all the grains of sand on the various vast deserts around earth?)

For number two I would assume NO as the analogy says all the grains of sand on the earths beaches a beach.

Re: What is Webb observing now?

#56

Post by wang_li »

_trampeltier wrote: post #49
basil-rash wrote: post #46

Earlier quoted context omitted.

> only look good when processed Ehh. I personally can’t stand all the post processing folks love to make their results look “magazine ready”. I think the most minimal transformation possible to map the data into 0xRRGGBB would look the best, ideally with a simple standardized algorithm that doesn’t allow for any “artistic license”.

IR pictures would be not RGB, just black/white (or whatever palette you like). But yes, it would be possible. For ex. from Flir Thermal cameras, you also can output the image just as spreadsheet. You can even choose the values as temperature (which is calculated) or just as energy (what the sensor gets).

Light isn’t RGB. We just receptors that react to certain wavelengths. I suspect the sensors on the telescope have a range of wavelengths they are sensitive to. It would be a straightforward translation to shift it to map it to the visible spectrum without varying the relative intensities to accentuate certain aspects of the image.

Re: What is Webb observing now?

#58

Post by mr_mitm »

asdff wrote: post #51
basil-rash wrote: post #46

Earlier quoted context omitted.

> only look good when processed Ehh. I personally can’t stand all the post processing folks love to make their results look “magazine ready”. I think the most minimal transformation possible to map the data into 0xRRGGBB would look the best, ideally with a simple standardized algorithm that doesn’t allow for any “artistic license”.

It would be nice if they stopped with the false color, and just scaled it to whatever color an astrounaut might see from that point of view.

Besides the wavelength being outside of human perception, an astronaut wouldn't see anything due to the low photon flux. These pictures have a very high exposure time.

Re: What is Webb observing now?

#59

Post by __egb__ »

ianburrell wrote: post #45
skybrian wrote: post #39

I’m getting the impression that some people don’t know what they’re looking at. It says “Background: Two Micron All Sky Survey” which you can read about here [1]. This is not a live image. It’s just showing you where it’s pointing, which isn’t so meaningful for most of us. (It’s random-looking stars.) You can read interesting details about the current observation at the top, though. Currently: * A census of high-reds…

Webb won't ever provide a recent view since the images belong to the research group and are only made public when the results are released. Also, Webb can't provide a video feed since it is taking long exposures, and probably only sends results back to Earth when image is finished. The images are in the infrared and only look good when processed.

To expand on this, Webb uses the Deep Space Network (DSN) to communicate with us. It can’t stream data back 24/7. There are generally three contacts per day each lasting a few hours, but I believe this is dependent on the scheduling of contacts with other missions that also use the DSN.

Also, the science data that is sent back is a stream of packets from all the data that was taken since the last contact. The packets are arranged for efficient transmission. One of the first steps of the science data processing is to sort the packets into exposures. Often packets for an exposure are split among multiple SSR (which stands for solid-state recorder) files. Sometimes there are duplicate packets between SSRs (data sent at the end of a contact is repeated at the beginning of the next contact). Only when the processing code determines that all expected packets are present—by using clues from other subsystems—can the next step (creating the uncalibrated FITS) begin.

If anyone is interested more details, the packet stuff is based on standards from the Consultative Committee for Space Data Standards (https://public.ccsds.org/Publications/BlueBooks.aspx).

Re: What is Webb observing now?

#60

Post by olddustytrail »

system2 wrote: post #10
gigatexal wrote: post #2

This is so very, very cool. I did hear some horrible news. Seems the funding for the next-gen (or even current maintainence of) Chandra-X ray observatory (space based telescope) won't get approved which is a huge shame. Maybe politicians could be persuaded by sites like these and greater awareness campaigns to not lose such a worthwhile instrument for science. And if it does is there an international equivalent maybe…

Politics and religion slowed down our space exploration by many thousands of years.

Indeed, if they hadn't made the pyramids so heavy they could have been spaceships!
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