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I'm equally or kore as impressed with the background with soo many galaxies peaking out. Any time the jwt points to space the galaxies are everywhere.
Same here. It just boggles the mind
I wish we could see an overlay of distances like how many au is that wisp of gas and dust
Around a half of a light year, based on the zoom out of the segment they imaged in the article. The head is like 3LY across.
Edit: 0.79LY across - see my calcs in my later comment!
I hope someone can do the math… how many mi/km is each pixel?
I calculated 1.12 billion miles per pixel, very close to what the other user got (but I believe they assumed my 0.5 LY guesstimate and 1987 pixels, see below for a more complete calculation)
This is based on the image having an angular footprint of 2.1 arcminutes. I converted that to radians, used tangent to find the width of the image in light years assuming the 1300LY distance to the nebula. The actual width of the image is around 0.79 light years after calculating that.
Dividing that by 4159 (number of pixels wide in the TIF) and converting to miles, you get 1.12B mi. Which is essentially the NIRCam imager’s resolvability at this distance.
Double it if you’re assuming the .png used in the article.
For this photo (the full res version of the photo the article is linked to, 1987px wide), it'd be about 1.5 billion miles/2.4 billion km per pixel.
Edit: See u/RedLotusVenom's comment for a more accurate breakdown.
For those seeking something more relatable than billions of miles:
1.5b miles per pixel = ~16 au.
An astronomical unit is equal to the average distance between the earth and the sun.
So one pixel in this image is approximately the distance between Uranus (19au) and the Sun.
Another fun way to think about this is it would take light approximately 130 minutes to pass the equivalent distance of a pixel in this image. Is that bigger or smaller than you expected?
Probably longer than expected? Though I’m not super sure because I wasn’t sure what to expect. Space is unfathomably large, so I don’t think I would have known where to start guessing
(Disclaimer, I came to the comments to ask this question just out of sheer curiosity before seeing the other, more negative thread. But I’m gonna ask it anyway because I don’t see any decent answers in there)
So knowing that JWST doesn’t capture the visible spectrum and all of these are processed, how close are these images to what human eyes might actually see if they were theoretically close enough to have this field of view?
It's hard to say...the length of exposure times make even the darkest parts of the night sky look insanely bright, as they are being "falsely" lit. If you were in space, close enough that the above photos were basically your field of view, the colors would be similar, and you would possibly be able to see, but it would be soooo much tamer. A good example of this effect is to look at the milky way with your eyes, then see someone's long exposure. It's not doing anything to change the light/colors, but there's no way your eyes would ever be able to see that by themselves. The horsehead nebula, from what I can gather, is very much this. You would largely see very little without knowing what to look for, but it's still accurate coloring.
The point being that just because our very limited human eyes don't see it doesn't mean that it isn't there.
Agreed, everything is there as photographed, just some of the photos are enhanced to display the detail or taken in spectrums that our eyes would be unable to pick up on.
What’s crazy. Seeing the Milky Way with your own eyes is so much more impressive than the pictures people take of it, even with the relative lack of detail.
I guess it's about how you look at it. I consider them both equally awe inspiring, but to each their own
ahhhh that 100% makes sense, thanks
Well as a start the horsehead nebula is very red because of the Hydrogen alpha emission line (not the head itself, which is a dark nebula and is just black), many amateurs capture images of this target with a stock DSLR/mirrorless camera.
But even if you were right next to this thing, you wouldn’t see anything. It is simply very dim, you can see a part of it without really any color with a big enough telescope from a dark site but you would need long exposure photography to see it in its full color and detail. Deep sky objects don’t appear that small from here on earth, the problem isn’t magnification but rather brightness.
Generally when you look at nebula in a telescope with your eyes, you can only just see the brightest parts as very very faint smudges. The colors are going to be very subtle, like how the stars just have a hint of blue or red color to them. You can see the Orion nebula without a telescope, even in a city. It's just a slightly blurry star though.
Forget the nebula, look at all those galaxies... Insane. There's also bound to be some kind of life in most of those.
Insane is exactly what I was thinking. Can we even truly comprehend the scale?
Nope. Its vastness is part of the appeal. And then you could multiply the vastness by an unfathomable amount if you factor in the possibility of multiple universes .........
The quantity of galaxies in this incomprehensibly tiny speck of the sky is staggering. There's nothing that could appropriately convey the sheer sense of scale at play here, and it's charmingly frightening
What causes some objects viewed by JWST to have the hexa-pattern? I know that particular pattern is due to the shape and configuration of the JWST mirrors, but what determines whether a viewed object shows it or not?
I believe it’s mostly just closeness. The stars we see with that pattern are in the Milky Way galaxy. (I could be wrong).
It has to do with how much light is concentrated in a certain size of small area, relative to the exposure time and sensitivity and such.
Basically, every single "pixel" (it's not actually tied to pixels since it occurs in the optics before the CCD but it is related to its maximum resolution so it's easier to explain in that way) has that pattern attached to it, called diffraction spikes. The brighter the "pixel", the brighter the spikes, and the brightness fades out along the length.
You see this most on stars in our galaxy because they concentrate a lot of light into a single "pixel" (further stars would appear dimmer), so the spikes are super bright as well and are bright enough to see down a lot of their length. But when the object is, say, a nebula, those spikes come from every point and blur together, and since the image is exposed for the nebula (that's what it's trying to image after all), the fact the spikes are a lot dimmer makes even the blurring together much less visible.
So in short, you primarily see the diffraction spikes on things that are overexposed (they're also related to lens flares in more typical cameras)
Does it work in a similar way for all telescopes that have diffraction spikes?
Basically, everything shows it to some extent, but it only becomes noticeable on objects that are overexposed, particularly point-like ones, which foreground stars pretty much always are. You can see my other reply to the other commenter for more detail
When I read my first astronomy books, back in the sixties, they told me that we would never see stars other than as mere points because they were too far.
Never trust science books, they are full of lies 😈
At the time that book was written, 60-70 years ago, that might not have been a lie. They might have simply been unable to imagine the power of technology in the future.
That's not a lie. That is a lack of vision on the editors' part. There is a difference between being wrong, which is acceptable/expected in science, and lying. The CEO of IBM once said that 6 or 7 supercomputers would provide more computing than the world could ever need. Computers would create paperless offices. Are these lies or lack of vision?
Can't you spot a joke? Do you think a "sceptic" would hang out here?
In a world where science takes a back seat to talk show doctors and a Playboy model, I'm going to error on the side of missing the joke. If people had taken Jenny McCarthy as a serious threat to public health from day 1 instead of laughing her off as a joke, we might have avoided much of the the Covid vaccine fiasco and we could have avoided multiple measles outbreaks in colleges that were due to refusal to vaccinate.
Because the CDC didn't jump to conclusions in the first days of the pandemic, their hesitancy and seeming changes of position were seen as lies, not changes due to learning more. Lies are a serious accusation and tear away the integrity of the one lying.
When I see somebody making a blanket statement that science books and scientists lie, I take that seriously. That is the attitude of too many people in this country-that learning science is optional and believing it isn't useful. This opinion in the country at large is why I found myself trying to explain the how/why of the last eclipse happened to 20 year old people (the moon orbits the earth which orbits the sun level of explaining). I'm not saying text books can't be forced to print non-science (Texas needs watching), or some scientist won't manipulate their results (the big thrust of the vaccine scare was a based a lie to sell his particular vaccine), but I don't see the joke on a blanket statement.
/s and there would be no problem, lol. I'll admit I could interpret the devil emoji as making it a joke. But, since I see this sign weekly, , I slide all devil stuff into the "that's religion for you" pile.
Looking at that photo makes me really think how impossible it is that we are alone in the universe. So many galaxies and so much spaaaace for more stuff out there! amazing
I have a hard time understanding how all of this works. JWT didn’t just “snap a pic”, right? This is something generated based on the data the telescope collects?
Can anyone else other than myself imagine all these galaxies going around, orbiting a center? For example, the observable Universe goes out 14 billion light years. Go out another 100 billion and you reach the center of this Universe's black hole. I tend to offend so many with this theory. "HA, SHOW ME THE PROOF", some say.
I imagine a universe which extends inward as much as outward. Atoms look fairly similar to solar systems. What is inside of an atom? And inside that? And inside that? You could keep going infinitely
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They really messed up with stars being too bright with that Starburst pattern. I know its an artifact from the mirror and lenses but... it just takes away too much from the images for me.
This is the dumbest take I've read all week. Congrats
Diffraction spikes are a major issue and the James webb is worse than most. Dont take it so personally.
There's nothing personal about it. Your take is devoid of sense. Just another dimwit commenting on something they clearly know nothing about.
I look at the picture for Horseheads nebula and all I see is a giant Starburst and a grainy image that looks worse than hubble. You don't need to know anything to be able to compare two images.
I'm sure it can help scientists learn about our universe but that doesn't change the fact it takes crappy pictures