Ahkshually, the “Pillars of Creation” is not a true-color picture.
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Yep, the various emission spectra are mapped to distinct colours that don’t line up to their real-life counterparts. But! the cloud is in the visible light spectrum.
Another example: Between November and February is “Orion nebula season”. It’s a gorgeous, awe-inspiring ghostly green when you’re just using an eyeball and a telescope, with sweeping tendrils of cloud light-years across. I find it mind-blowing. The images you see online with the oranges and reds and blues are all mappings of visible light, and they do mean something, but it’s definitely not how the eye sees it.
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That line. Lol. I watching this movie tripping hard, and I knew what he was talking about.
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How would you say it compares to the Jewel Box star cluster? 
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Okay. It’s out. What was the album?
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Well spotted!
And they’re mysteries, one and all. In a few million years, the Orion nebula might look very much like the Jewel Box cluster, once it gets past “star forming” and turns into an open cluster.
When you consider that the universe might carry on for hundreds of billions of years after the last stars have formed and gone out (there’s only so much hydrogen), it’s a mind-boggling time to be alive. We can look up and see stars being made.
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For all the spectacular imagery we got from Hubble, all of it was artificially processed. Hubble takes black and white photos and meticulous work is done to process all the data streams to create the final images. While they are intended to be true-to-life representations of what you would actually see, they aren’t really indicative of what Hubble actually photographs.
There’s no reason to assume Webb’s optics won’t result in similarly spectacular pictures once they are fully processed.
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I’m going to be the designated idiot: I don’t understand how this is the sharpest image of this star, and yet it has these huge… mirror flares or whatever they’re called.
Aren’t those spikes hiding the true shape at the surface of the star? Isn’t the added light obscuring other data? Doesn’t someone now need to go in and post-process this?
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This image shows a severely over-exposed star. The point of the overexposure is to see the six spikes, which are the result of the mirror segment edges diffracting the starlight.
This diffraction is entirely a function of the geometry of the mirror segments. It’s impossible to get a more clear image from this mirror due to the edges being straight lines.
This is an engineering test. A properly exposed image of the same star will not show these six spikes.
The random galaxies in the background are a bonus, and hint of the stunning images we’re due to see in a few months.
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Probably the most reliable source of disappointment in astronomy is photographs of nebulae. Those gorgeous colours are the result of a) hours of exposure, and b) lots of careful colour-mapping.
In real life, they’re so dim that looking at them through a telescope is like looking at a Van Gogh painting in a dark room. Compared to the photos, all you often see are weird smudgy swirls.
Example: the Horsehead nebula.
This amazing thing is about a quarter the size of the moon, and it was discovered almost three centuries after the invention of the telescope, in 1888 by Williamina Fleming. She wasn’t looking through a telescope - she was poring over astronomy photographs when she noticed something odd that seemed to be worth further investigation.
It wasn’t hidden behind anything. It’s just too dim to easily see with just eyes and a telescope.
Point is - astronomy photographs aren’t always meant to copy what your eye can see through the telescope. Often, they’re used to look deeper. You’re absolutely correct - anyone who says infrared won’t look as “wow” in photos isn’t familiar with how astrophotography works or what it’s for.
I’m really feeling quite impatient about this telescope. 
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The great nebula in Orion looks very disappointing through my 6" Schmidt-Newtonian. A patch of gray fuzziness with some bright stars in the center.
I also explained to my daughter that every depiction of nebulae on TV is a lie. They don’t get any brighter as you get closer, because as you get closer the nebula is also spreading out before you at an equal rate. Even if you were IN a nebula you’d hardly be able to tell.
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I’ve got a family holiday planned to a place with very dark skies in a few months; it’ll be my first time with a telescope. Looking forward to seeing the difference. And trying to temper my expectations.
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The Andromeda Galaxy is larger than the moon in the sky, and it’s in the northern hemisphere—we can’t see it with our naked eyes because it’s so dim
It makes sense galaxies are dim, really—after all, they’re almost entirely empty space
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There are still lots of places where the sky is dark enough that you can. It’s only magnitude 3½, in my experience only a little harder to see than the Milky Way in the sky. All that shows up is a fuzzy blob, of course, but it’s neat to know that’s the oldest light you can see without equipment.
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Technically, they’re diffraction spikes. They’re an artifact caused by the supports for the secondary mirror
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Huh. I’ve seen the spiky images in astrophotographic images, and I’ve seen pictures of telescopes with those cross-shaped supports, but I never put the two together…
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These six big diffraction spikes are the result of the segmented primary mirror edges. They’re the equivalent of the lens flare lines caused by the edges of the iris in a photographic camera lens. The two smaller horizontal ones are said to be from the vertical secondary support.
The impressive thing about the image of these spikes is that you can see fringes in them, meaning that the mirror segments are perfectly aligned with each other.
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By which you mean about a quarter of the diameter as viewed from Earth, right?
(It always annoys me when TV and movies show the Earth being huge in the sky from the Moon when really it is only about as big as the thumbnail on an outstretched hand. Not that you should take your spacesuit gloves off to check.)
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Earth looks 4x wider from the moon as the moon does from the earth, so a little larger than a large egg held at arm’s length. But yeah not massive by any measurement.
ETA: upon careful reading this is what you said. Derp.
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