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Looking at images for the planets of the solar system in all different wavelengths, I was wondering whether we can deduce any information about the planet itself without using anything other than an image.

An image of a planet is like the one for Jupiter on the Wikipedia page. Any info would be appreciated.

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    $\begingroup$ Do you mean one image or all images through all wavelength combined? Do spectral images count? How narrow may filters be? $\endgroup$
    – planetmaker
    Aug 19, 2022 at 23:38
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    $\begingroup$ Well - (kind of obviously) you get information about what the planet looks like. You can tell from looking at Mercury that it has no atmosphere and an ancient cratered surface so no plate tectonics. You can tell that Jupiter is a gas planet. You can tell that Saturn is surrounded by a huge ring system. Thats all information. But I suspect you are asking something else. $\endgroup$
    – James K
    Aug 19, 2022 at 23:42
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    $\begingroup$ @planetmaker Well, I'd like to know about every aspect. So, if you have any info regarding images of planets with one wavelength or all wavelengths combined, please share them. The same goes for spectral images and filters. $\endgroup$
    – Belal Bahaa
    Aug 20, 2022 at 0:25
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    $\begingroup$ @BelalBahaa This is a great question! I think that the best answers will draw in part from history; for example before spacecraft visited the planets all we had was images from telescopes on Earth, taken through the atmosphere. So a good Astronomy book from the early 1970's will be very helpful. Of course they had radio telescopes then so the magnetic fields of some planets were known as well. $\endgroup$
    – uhoh
    Aug 20, 2022 at 12:19
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    $\begingroup$ Per en.wikipedia.org/wiki/Black-body_radiation you might be able to get some idea of temperature, although this stretches the definition of "image" since it includes frequencies outside the human visual range $\endgroup$
    – Barry Carter
    Aug 20, 2022 at 15:18

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Since you specified "an image", I'd rule out any spectral information from this attempted answer. An image in the following context refers to a grayscale image taken at a narrow band filter/wide band filter/ a single wavelength 2-D image with some decent spatial resolution. However for the following to make sense, I'd make myself the luxury of having more than a single image, ideally a sequence of images of the same object/ planet acquired during a short period of time (hourly/ daily).

History tells us that early scientists were able to decipher the rotational period of objects, ex. Mars by looking at them through telescope. Basically, you follow a surface feature (why I said decent spatial resolution above) that is sticking out and observe when it returns to its original position and the time elapsed will be the orbital period of the object observed. Since you did mention "an image", this calculation could be made more precisely using a computer. If you check out this wikipedia link, you'll notice some surface features on Mars, referred to as albedo features due to their differences in brightness, similar to the red spot on Jupiter, that you can also follow as it rotates. In the case of Mars, this led to the detection of its polar caps which fuelled a lot of debate and development of science on Mars over the years.

One could also potentially determine the tilt of the rotation axis of the object using this same method. So you look at the path traced out by the surface feature of interest during its rotation.

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