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What is Webb observing now?

spacetelescopelive.org

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Re: What is Webb observing now?

#71

Post by 1123581321 »

basil-rash wrote: post #63
BurningFrog wrote: post #52

Earlier quoted context omitted.

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

Yes, that is what the map does. Convert values from one domain to another. That is the purpose of mapping. The point is to make it as simple and consistent as possible.

Are they not doing that? What is the origin of the idea that they sit on the images too long choosing a custom wavelength conversion formula? Is it just that their images look good?

Re: What is Webb observing now?

#72

Post by febed »

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.…

Forget the universe, just consider the size of the Milky Way. If the Milky Way was shrunk down to the size of United States, the Earth would be smaller than the gap between the ridges in a fingerprint.

Re: What is Webb observing now?

#73

Post by dotnet00 »

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…

The politicians aren't going to be persuaded by this, they're corrupt snakes who are very open with their lack of regard for actually useful programs.

Chandra et al are dying because Congress wants to pour more money into SLS (and thus into Boeing), but is unhappy that NASA isn't playing along (choosing SpaceX and a similar lander from Blue Origin, buying high risk, lower cost robotic landers from space startups). So they give NASA more money than they ask for when it comes to SLS, dont allocate enough to other Artemis goals and cut the overall budget.

Re: What is Webb observing now?

#75

Post by light_hue_1 »

wang_li wrote: post #56
_trampeltier wrote: post #49

Earlier quoted context omitted.

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.

That's not how vision works. You see an extremely post processed image that's extremely far away from the original light that hit your retinas. There's nothing at all privileged about shifting something into the visible spectrum directly and seeing junk. You're just making an image that your visual system isn't good at understanding. It's not pure, it's garbage. You would hallucinate things that aren't there, you would miss obvious things that are there, etc. For you to really comprehend something the transformation needs to be designed.

Re: What is Webb observing now?

#76

Post by alt227 »

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.

You have 2 choices for these images, false colour or black and white. Anything else is false.
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