Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

James Webb first images – complete set of high resolution shots now live

webbtelescope.org

Post reply on HN
Print view View original

231–240 of 410 posts

Re: James Webb first images – complete set of high resolution shots now live

#231

Post by deanCommie »

historynops wrote: post #10

A lot of the pictures have some bright stars with 6 long lens flare like points coming out of them in a consistent pattern. Is that because of the hexagonal shape of JWT's lenses/mirrors?

From the other comments, I understand why it's there, but i wish they would photoshop them out.

The images take on a more synthetic and fake quality when the technical physical man-made constraints of our telescope get projected out onto the natural very much NON-man-made universe.

Look at https://stsci-opo.org/STScI-01G7ETPF7DVBJAC42JR5N6EQRH.png and observe the incredible entropy in the nebula itself. The consistent, perfect, straight lines, of each star are jarring in the image.

Re: James Webb first images – complete set of high resolution shots now live

#232

Post by AnonMO »

moffkalast wrote: post #204
AnonMO wrote: post #187

Earlier quoted context omitted.

It took like 5 months to cool web to operational temperatures rolling the telescope would create so much heat all new images would be useless until it cools down again.

That makes no sense, they have to rotate it every time they take a picture otherwise they'd be looking at the same spot all the time. Motors don't emit that much heat and neither do torque wheels. Though I suppose now that I think of it, it's possible the main mirror assembly actually has no built in roll control but only pitch, since the yaw part could be done by moving the entire telescope while remaining shaded. I…

LUVIOR is not web. Web doesn't have articulation like LUVIOR its fixed only the mirror segements move. also they don't rorate everytime they take a picture there's limitations beacuse its an infered telescope. https://jwst-docs.stsci.edu/jwst-observatory-characteristics.... Web also has a field of view 15x hubble

Re: James Webb first images – complete set of high resolution shots now live

#233

Post by turdnagel »

This kind of stuff is really awe-inspiring. I have a couple of questions for anyone who is knowledgeable on the subject:

1. Looking at the light from the tiny red-shifted galaxies that are ~13 billion years old... would the Milky Way appear the same to an observer ~13 billion ly from us?

2. What is the cause of the star pointed artifacts (specifically, having 6 major "points") for particularly bright objects? If you zoom in closely on any one of the points, you can almost make out a hex grid, as if the shape of the telescope's mirrors is the cause. Is that correct?

Re: James Webb first images – complete set of high resolution shots now live

#234

Post by j0e1 »

chaps wrote: post #64

Direct links -- Stephan's Quintet (NIRCam and MIRI Composite Image): https://stsci-opo.org/STScI-01G7DB1FHPMJCCY59CQGZC1YJQ.png Southern Ring Nebula (NIRCam and MIRI Images Side by Side): https://stsci-opo.org/STScI-01G79R28V7S4AXDN8NG5QCPGE3.png “Cosmic Cliffs” in the Carina Nebula (NIRCam Image): https://stsci-opo.org/STScI-01G7ETPF7DVBJAC42JR5N6EQRH.png Webb's First Deep Field (NIRCam Image): https://stsci-opo.org…

> “Cosmic Cliffs” in the Carina Nebula (NIRCam Image):

> https://stsci-opo.org/STScI-01G7ETPF7DVBJAC42JR5N6EQRH.png

Is this for real?! It looks like it came right out of a Sci-Fi movie/book. Could anyone explain how much of this is post-editing magic?

Re: James Webb first images – complete set of high resolution shots now live

#235

Post by yvoschaap »

oAlbe wrote: post #229
racingmars wrote: post #221

Earlier quoted context omitted.

The image details do have the dimensions listed in a standard measure down under the "Fast Facts" section; I assume this will be included for every image release. The deep field image says it's about 2.4 arcmin across[1], Stephan's Quintet image is about 7.4 arcmin across[2], etc. [1] https://webbtelescope.org/contents/media/images/2022/035/01G... [2] https://webbtelescope.org/contents/media/images/2022/034/01G...

Is there a way to rapport an arcmin to a measurement that would be more easily understandable? Not necessarily as a multiple of grains of rice.

7.3 arcminutes = 16 light-years

Re: James Webb first images – complete set of high resolution shots now live

#236

Post by pkaye »

whiteboardr wrote: post #137
jacquesm wrote: post #99

Earlier quoted context omitted.

The difference between 'actual science' and 'some touched up version of objects in our universe' is smaller than you might think: no matter how good your eyes, if there was no frequency shift involved you would not be able to perceive the image, other than as an array of numbers. To facilitate your consumption of the data it has to be frequency shifted and the easiest way to do this is to map the IR intensity to a ra…

Thanks, but how is the sausage made then? Guess, that’s my main question. I get that the aquired data needs to be transformed in a way so we get an image that depicts a reality we can visually process. I honestly thought there’s some tools in Nasa’s imaging group that, based on scientific rules, pumps out an image that is correct - seeing Photoshop in use left me wonder… I get that the investment needs to be “sold” t…

They do have some custom tools that are publicly available. I saw some videos in the past showing how they use those tools along with Photoshop to process images.

Re: James Webb first images – complete set of high resolution shots now live

#237

Post by mwint »

yvoschaap wrote: post #235
oAlbe wrote: post #229

Earlier quoted context omitted.

Is there a way to rapport an arcmin to a measurement that would be more easily understandable? Not necessarily as a multiple of grains of rice.

7.3 arcminutes = 16 light-years

Wait, but it’s a ~cone, right? So it must be 16ly across at some specific distance from us?

Re: James Webb first images – complete set of high resolution shots now live

#238

Post by nacogo »

bdefore wrote: post #151
quaintdev wrote: post #48

Earlier quoted context omitted.

A GIF comparing both Hubble and JWST https://i.redd.it/9uyhwijeo0b91.gif

The additional detail of the red spiral galaxy around 12:30 is stark by comparison to others. Any ideas on why?

The reddest objects in the JWST are frequently not even present in the Hubble image, as they were redshifted into a band of light Hubble couldn't even detect. That's my favorite part about this image - those galaxies we can now see which were previously redshifted beyond our capacity to detect. They're the oldest, and receding from us the fastest.

Re: James Webb first images – complete set of high resolution shots now live

#239

Post by DrBazza »

jcims wrote: post #205
pwned1 wrote: post #168

Earlier quoted context omitted.

My god, look at the background of the first image at full scale.

I really wish astronomers would come up (or use) a standard mechanism for indicating the field of view of an image. The scale of this one in the night sky is much larger than the deep field one.

Grain of sand at arms length for yesterday’s deep field.

Re: James Webb first images – complete set of high resolution shots now live

#240

Post by WhompingWindows »

silentsea90 wrote: post #31

Way to brighten my day with awe and wonder, way to ruin my day with existential dread about our place in the universe.

Why existential dread? We're extremely lucky to be alive. That one sperm hit that one egg and we survived to now. That is extremely unlucky, each of us is one sperm out of hundreds of millions, so savor this existence!!
Post reply on HN