Thanks for finding those images! I threw together a page that lets you compare them via a slider. You should be able to zoom in on mobile!

https://blog.wolfd.me/hubble-jwst/

The .gif comparison was a bit... upsetting since the color palettes are so limited and the resolution is so low, so it really didn't put JWST _or_ Hubble in a good light.

This is incredibly useful. Thank you!

would it make sense to balance the two images in terms of brightness? the hubble one just seems dimmer.

There is some extra "pinpoint" clarity in the Webb image, but it doesn't show (for instance) a bunch of new stuff, I was surprised at that.

There is definitely new stuff there – if you look closely.

The new stuff is of course faint and small. Otherwise Hubble would have seen it!

It looks like restoration of an old painting where the aged, yellowed varnish is stripped away to reveal the (much brighter and more detailed) original painting below.

Couldn’t you just do basic photo touch ups to get the Hubble to look about the same???

No. Webb looks deeper into the infrared and can see galaxies that Hubble can't see. There're some red galaxies in Webb (upper-right especially) that aren't in Hubble's at all.

amazing progress

All the very red galaxies in the JWST image are mostly or completely invisible in the Hubble image. That’s because they’re so redshifted that they’re out of the spectrum Hubble can see. Those are the galaxies that are really far away.

Here's a variant of that GIF that separates out the blue, blue+green, and blue+green+red channels, to (hopefully) highlight which differences are due to the longer wavelengths (and which look more like exposure time difference). Webb's color mapping roughly aligns with the RGB channels, so I think this is meaningful [0].

https://i.ibb.co/D8dW6v5/jwst.webp

[0] https://webbtelescope.org/contents/media/images/2022/038/01G...

("...the assigned colors are: Red: F444W Orange: F356W Green: F200W + F277W Blue: F090W + F150W")

Steps to reproduce:

    convert 9uyhwijeo0b91.gif[1] -resize 4537x4630 aligned-hst.png
    cp STScI-01G7JJADTH90FR98AKKJFKSS0B.png jwst-rgb.png
    convert jwst-rgb.png -channel R -fx "u*0" jwst-gb.png
    convert jwst-gb.png -channel G -fx "u*0" jwst-b.png
    convert -delay 150 -loop 0 jwst-{b,gb,rgb}.png aligned-hst.png my.gif
    ffmpeg -i my.gif -loop 0 my.webp

Comparing both images, there is a perfectly round red dot that's just a few pixels wide, a little up from the most prominent star, which doesn't correspond to another object in Hubble's image. Is that an image artifact or some laser guide?

Could be an internal reflection. The optical path for many JWST instruments is, uh, compact: https://www.esa.int/ESA_Multimedia/Videos/2021/09/Webb_MIRI_... (Every kilo on telescope structure you save by folding the optical path is a kilo you can add in propellant, extending the working life of the spacecraft)

Instrument internals are painted black and heavily baffled, but nothing in optics is perfect. Dithering the direction the telescope is pointed in and image stacking should cancel out most optical artifacts, but internal reflections will be worse for bright objects like stars, which JWST probably isn't usually going to be observing with the imaging instruments.

It is a bit suspicious looking, but there's a lot of very red objects that the Hubble image doesn't catch. Presuming that the red colors in the images are the deeper infrared wavelengths (and thus the most heavily-redshifted objects) I would guess that Hubble just didn't have the detectors to see those.

Aren't the red ones moving really fast away from us and the white ones more "stationary" from our point in the universe?

Yes, that's generally true. Galaxies that are redshifted are moving very fast relative to us. But the only reason for them to be moving so fast is due to the expansion of the universe, and these galaxies being sufficiently far away.

The large white elliptical galaxies in the center of the image are in the "foreground", while the orange-ish galaxies are much farther away in the background. This is why the light from the more distant galaxies is curved and distorted by the foreground objects, creating the lensing effect that we see.

Hubbles law says that astronomical objects that are further away also move away from us more quickly with the constant of proportionality being the Hubble constant

Same comparison zoomed into my favorite part without motion: https://twitter.com/sprigland/status/1546633629236748294

Incredible. If each of those galaxies has on average a few hundred billion stars (our is estimated to have between 100b-400b), and each of those little dots is an entire galaxy, well, that's a lot of stars in this image.

People use the term mind-blowing loosely but it really fits here. That’s an utterly astounding, incomprehensible number of stars.

And this image is “roughly the size of a grain of sand held at arms length” of the night sky.

> And this image is “roughly the size of a grain of sand held at arms length” of the night sky.

For a more specific measurement: NASA says 2.4 arcminutes across[0].

[0]: https://webbtelescope.org/contents/media/images/2022/038/01G...

a brief peek into infinity

Not really - there is a fairly definite ending about 13.4b light years into the image.

I think you're referring to the age of the universe here? But due to inflation, although the universe is 13 billion years old, the observable universe is quite a bit bigger than that (i.e. we can see stars much further than 13 billion light years away).

I was thinking of the age - good point.

Lots of planets, too. Some, with life.

Since we're looking at objects billions of light years away, we're looking billions of years into the past. In the context of extragalactic life, it's a bit sad to me that even if we somehow spotted it at those insane distances, in the early versions of those galaxies we see, odds are that it'll be gone by now, and we'll likely be gone by the time any lucky photons born in our solar system can reach those places, too. Even so, it's cool to think that the odds of life being out there somewhere in a universe so vast are really quite good, inaccessible as it may be.

Bro everything other then the alive is out there and all the aliens are on earth your just not capable of seeing them

Or maybe not. If you consider how improbable is the origin of life on the earth then maybe it's not even enough planets in the observable universe to start a life. But the universe is much greater than its observable part.

What is the probability of life originating on earth?

We know it is anywhere from 0 (originated elsewhere and found its way here) to 1 (originated here and is guaranteed to originate given the conditions). I don't think we have enough data points to determine improbability yet.

What is the probability of life originating in the universe? We know it is definitely greater than 0..

you may like to read about the "rare earth" hypothesis and the "fine tuned universe" theory.

Do you have some books or articles you could suggest?

Call me gen Z but I prefer my knowledge in video form. Can highly recommend PBS Spacetime's coverage of the topics: https://www.youtube.com/channel/UC7_gcs09iThXybpVgjHZ_7g

Humanity has found aminoacids in asteroids. Given enough time and energy, it seems likely to me that structures would form and then evolve in complexity.

Agreed. I realized recently that planets not only need a goldilocks configuration but likely also need to have a liquid metal core to create a protective magnetic field.

It would still occur quite a bit, and some planets with a protective field likely still produce simple life forms.

Everything without life is out there the ones with life are all on earth yo NASA spends all its money on how to lie

If I knew JavaScript I would make a bookmarklet that makes it slowly pan over the full-res version, stopping periodically.

Since I don't, I made a poster of crops: https://twitter.com/KyeFox/status/1546629778349907968

Some that I found quite interesting:

https://ibb.co/zPvxrFT

https://ibb.co/NYsp9Jw

https://ibb.co/wJDQ7XM

https://ibb.co/yf8RTM2

https://ibb.co/d72g9Jx

https://ibb.co/BBPvFZf

https://ibb.co/567Z9RC

https://ibb.co/Hpm43Xr

https://ibb.co/JBhmCxL

https://ibb.co/PMYqnXb

Some of those shapes are just incredible, like the 4th that looks like a glimpse of what will happen shortly after the Milky Way and the Andromeda Galaxy will collide in a few billion years.

There's a great animation of it here: https://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way_co...

Can you elaborate why you found those interesting?

Mainly because most of the pictures I usually see of the galaxies in space, they appear as practically identical dots. Never before I've seen this level of detail and the variety of shapes. Each of these galaxies have billions of stars and planets and they are billions of such galaxies. I know we have read these numbers before but just seeing them "up-close" like this in such a small section just makes it that much more real.

Just imagine how much more vivid they would appear once the technology progresses ever further.

> Mainly because most of the pictures I usually see of the galaxies in space, they appear as practically identical dots. Never before I've seen this level of detail and the variety of shapes.

Do you mean these specific galaxies? If not, you can see many galaxies in amazing detail with very modest equipment. If you know what you're looking for you can faintly see Andromeda with the naked eye.

Terrible light pollution where I stay - hopefully one day I'll be able to retire to a place more conducive to stargazing.

Same where I am. If you have a dSLR even a 15 second exposure will show you Andromeda with light pollution. Time consuming hobby though :)

Haven't seen the Deep Hubble Field?

I think I did see one of them and it was pretty amazing but James Webb images are on a new level. Also, I did know Hubble but didn't know the name Hubble Deep Field - thanks for mentioning that because I searched for it and found this:

https://esahubble.org/images/?search=%22Deep+Field%22

There are images on that link that I haven't seen before and the level of detail is pretty amazing too.

I created a webp comparison: https://ibb.co/9ZjpLnV

James Webp?

Wow I love how things that were dots or haze with Hubble are brilliant spirals and galaxies in the JWST image. Absolutely amazing!

I always wonder if we had a sensitive enough instrument, would it get more difficult to pick out individual galaxies? Or, are there enough galaxies that an image taken by a very sensitive telescope would have no black areas?

Highly recommend the full-res image - brings out a great deal of character from a lot of the galaxies that is just not visible in the zoomed-out image.

How about 1.4 Gigapixel image of the galaxy? The new photos by @NASAWebb are stunning. Let's Enhance's AI made them super high res for you to enjoy the clearest view of the Universe.

Download: 80MP/140MB https://drive.google.com/file/d/150VhXVEfYXmr70LrrZxQ50pU0u5...

1.4GP/2.5GB (note: not every image viewer can handle a file this big) https://drive.google.com/file/d/14x__QDUmrIvLnlxoSOksu3mgpeX...

I've created a zoom & pan version of the full-resolution image - https://example.sirvtest.com/nasa/universe.html

What is the exposure difference between the Hubble and JWST images?

I couldn't find an exact exposure time for the Hubble image, the press release by the ESA has this quote though: "This deep field, taken by Webb’s Near-Infrared Camera (NIRCam), is a composite made from images at different wavelengths, totaling 12.5 hours – achieving depths at infrared wavelengths beyond the Hubble Space Telescope’s deepest fields, which took weeks." [1] There is also another comment further down this thread stating Hubble was 140 hours. [2]

[1] https://www.esa.int/ESA_Multimedia/Images/2022/07/Webb_s_fir... [2] https://news.ycombinator.com/item?id=32063214

Those exposure times (weeks / 140 hours) are for these images [0,1], Hubble's deep fields. Hubble's photo of this galaxy cluster, the one our root comment shows superimposed over JWST's, took 5 Hubble orbits [2]. I think that's around 2-3 hours of exposure time.

[0] https://en.wikipedia.org/wiki/Hubble_Deep_Field

[1] https://en.wikipedia.org/wiki/Hubble_Ultra-Deep_Field

[2] https://archive.stsci.edu/prepds/relics/ ("For each cluster, the team observed to 5-orbit depth with ACS and WFC3/IR")

(If you want to verify [2] is talking about the same photo, you can retrieve it from the "SMACS J0723.3-7327" row, from the "Color Images" column/field).

LEO should be >= 80 mins so 5 hubble orbits should be >= 400 mins / 6.6 hrs?

EDIT: nasa.gov says 95 mins, so ~8 hrs.

Yes, but Earth obstructs the field of view for about half that time. The way HST refers to an "orbit" for scheduling, only part of the elapsed time is usable observational time, for a single target.

https://hst-docs.stsci.edu/hsp/the-hubble-space-telescope-pr...

- "HST GO observing time is counted in terms of orbits. Each 96-minute orbit contains a certain amount of useful time when the target can be observed, called the orbital visibility period..."

Ah right, because it is basically in LEO so the Earth is enormous.

> This deep field, taken by Webb’s Near-Infrared Camera (NIRCam), is a composite made from images at different wavelengths, totaling 12.5 hours – achieving depths at infrared wavelengths beyond the Hubble Space Telescope’s deepest fields, which took weeks.

12.5 hours total exposure for the JWST image, "weeks" for the HST image

Is the actual comparison HST image being used here from the hubble deep field?

EDIT: Doesn't look like it is -- it is from a more recent 2019-published study of SMACS J0723.3-732 as part of the Reionization Lensing Cluster Survey (RELICS).

Some background info in this paper:

https://arxiv.org/pdf/2207.05007.pdf

Although that paper does mention that this image is the deepest image of the Universe to date, and that the Fine Guidance Sensor image may be the second deepest, both exceeding the Hubble Deep Field image.

I think it was around 20 days for the Hubble and around 12 hours for the JWT