Stars and nebula are really big. If you can for example see a mountain that is 30 miles away with a telescope that doesn't mean that you can count the eyelashes of a person only a mile away. The mountain is so much bigger than the eyelashes that even at that distance it is much easier to see.

For example the Carina Nebula is 230 light years across, while a planet like Jupiter is 139,820 kilometers in diameter. So that is 139,820 kilometers across vs. 2,176,000,000,000,000 kilometers across. Even if the Carina Nebula is much more distant it can be easier to see than Jupiter.

Because planets are too small. James Webb is looking at crazy huge things. It's like trying to look at a grain of sand 50 miles away with binoculars.

Planets outside our solar system are way, way, way, way, way, way, way too small and dim to be seen in any detail by any space telescope.

Stars shine with the light of nuclear fusion; planets can only reflect the light of their parent star, and the teeny tiny fraction of the light that they reflect is almost always drowned out by the star's light.

Nebulae can be dozens of light-years wide; the famous "Pillars of Creation" 7,000 light-years away are about four light-years in length, or almost forty trillion kilometers. The largest planets are only about 150,000 km in diameter, or 250 million times smaller than the Pillars of Creation.

We have viewed some planets. So far this is the best image we've been able to obtain. It's not great, this planet is about the size of Jupiter. https://mediaproxy.salon.com/width/600/https://media.salon.com/2022/09/hip-65426-inline-01.jpg (Note these images are all different spectrums of the same planet)

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James web have looked at exoplanets. But it will at best see them as a few pixels what can be done is to analyze the spectrum of the atmosphere. That way we can detect what gases are there and we live free oxygen is an indicator of life. https://www.sciencenews.org/wp-content/uploads/2022/09/090122_lg_jwst_feat-1030x580.jpg is a exoplanbet it observe. It is a gas gignat 20x the mass of Jupiter. This is the resolution it can get of a expolnaet

Planets are tiny and very far away. Here can you see Pluto from Hubble and New Horizons The max resolution of an optical system depends on the diameter of the aperture. For Hubble, it is 2.4 meters, and James Webb has 6.5 meters let's call that 3x the diameter. So Jamers Webb could only manage 3x the resolution of Pluto and compared to any exoplanet Pluto is large in the sky. This is ignoring any effect of the longer wavelength light that James Webb observe that reduces the increase relative to Hubble. New Horizons was very close to the Plut so it can have a lot higher resolution

The image from Jamew Webb and another telescope you see in the sky are surprisingly large. An extreme example is https://apod.nasa.gov/apod/image/0612/m31abtpmoon.jpg the moon and the Andromeda galaxy to scale. It might be 2.4 million lightyears from us but is a galaxy of billions of stars. It is the second largest thing in the sky after out own galactic core, the milky way. The sun are the same size of the moon in the sky. You can see the center of it with your naked eye as a white fuzzy area. It is hard to see because it is dim not because it is small.

IF you look at a image https://www.nasa.gov/image-feature/goddard/2022/nasa-s-webb-reveals-cosmic-cliffs-glittering-landscape-of-star-birth it is not the size of planets is is a gas cloud man

>Called the Cosmic Cliffs, Webb’s seemingly three-dimensional picture looks like craggy mountains on a moonlit evening. In reality, it is the edge of the giant, gaseous cavity within NGC 3324, and the tallest “peaks” in this image are about 7 light-years high.

The closes star to earth, except for our sun, is 4.3 light years. Pluto is 0.00055041 light years from us. Our solar system would be in around 1 pixel in that image. The image width is enough to include another star system

The Cosmic Cliffs is a part of https://en.wikipedia.org/wiki/NGC_3324 that is 11 arcmin in size 1 degree = 60 arcminute so 11 arcmins =11/60 =0.18 degrees wide The moon is 0.5 degrees.

If it was bright enough you would see it as more than a dot with your naked eye, you would see some structure. The angular resolution of a human eye is around 1 arcminute = 0.02 degree. It is not too small to see with a nake eye in the sky, it is just too dim for your naked eye

Pluto is 0.06 to 0.11 arcseconds. 1 arcminut = 60 arcsecond so when closed to earth it is 0.11/60/60 = 0.00003 degrees

This mean NGC_3324 is =0.18/0.00003=6000 times larger in the sky the Pluto

Humans have resolved a few stars to more than a single do look at https://en.wikipedia.org/wiki/List_of_stars_with_resolved_images where 1 mas =0.001 arcsecond. Pluto is 110 mas in size when larges resolved star except for out sun is 50 mas.

So James Webb has and will observer more exoplanets. The are at best a few pixels in size. The stuff you see it the image that fills the frame is surprisingly large in the sky, we talk about lighyear across. it is just dim and the telescope is very good at collecting light

Wow, Thank you so much for the detailed answer and the links will definitely check them out and give it a read. Really interesting.

I'd like to note that you can also see 13.6 billion light years away with your eyes. There's no limit to distance other than whether or not there's anything to see. Telescopes collect light; they don't somehow probe out to a certain point and stop there.

The functional limit is determined by two things: resolution and wavelength. For complicated reasons involving the expansion of space-time, anything really far away is going to show up as longer wavelengths than if you were close by it. The longer the wavelength, the bigger a detector you need to gain good resolution. JWST looks at part of the infra-red range, so it's calibrated generally for further objects than (for instance) Hubble was, and consequently the collection area (the mirrors) had to be a lot bigger. That imposes a limit of how detailed an image we can resolve.

Resolution itself is a bit more straightforward: sure, you can see far away, but how much detail can you see? Not much! Telescopes like this can see with many times the resolution of a human eye, but they're also looking at things that would be unimaginably tiny in the sky. Remember, if something is twice as far away, it will appear half as wide. And now we're talking about things many of orders of magnitude further away than anything you can make out in detail with your eye. That's the limit that's important here, not strictly how far away it is.

If you look at the moon with your eyes, you can see a decent amount of detail. You can see some different kinds of terrain. You probably can't see the small craters that cover its surface. They just don't take up enough angular size in your vision.

The sun, coincidently, is about the same width in our sky. Yet it is 400 times wider than the moon. It's also about 400 times further away.

Alpha Centauri, the sun's nearby star system, is about 100 million times further away from us than the moon is. To see one of the stars there in the same detail we can see from the nearby moon, we'd need a telescope with 100 million times the resolving power of our eyes. And we just don't have one. Not even Webb comes close. Webb has an angular resolution of about 0.1 arc seconds. The human eye can do about 60 arc seconds, so Webb's acuity is about 600 times greater than the human eye. That's great, but a very far shot from 100 million. And we're talking about something the size of a star, and one of the very nearest ones. Looking at a planet much further away...it's simply way out of our capability.

The cool thing though is that there are tricks we can use to add different observations together into higher quality ones, so we aren't as far away from the goal as it looks. But it's still very complicated and takes a lot of combined observing time, and you still need to target to be bright enough to detect well, which distant planets aren't.

*230 lightyears in radius

Other than the size of distant planets being much smaller than stars or galaxies. The other very important difference is that compared to stars and galaxies planets do not give off its own light. They only reflect the light from nearby source.

The difference is like seeing a candle over a mile away compared to finding a ball in a dark room. It's much easier for us to see the candle than the ball.

The way we find planets currently is by measuring if and by how much a star dims when the planet passes in front of the star. The more the star dims, the bigger the planet.

Space is huge. Even with the power of the JWST, planets and stars are still just tiny specks. Also, stars are very bright and will drown out nearby details, including planets.

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