Question how was JWST able to point towards Jupiter

Aug 25, 2022
i was wondering how JWST could take pictures of Jupiter if it is in the L2 point orbiting in a direction protected from the sun and facing "up" and "down" instead of facing radially outward
JWST can point to anything that is at least 85° away from the Sun
Wow, that's a wide swath it must avoid. The HST is about 50 deg., IIRC. But it does make sense given the larger mirror and IR sensitivity, not to mention the far improved sensors.

...but no more than 135°. Over the course of a year then entire sky is covered.
I don't understand this limit. I assume the Moon is an issue as well. Is that part of your figure? Can it view the dark side of the Earth, or is slewing there too risky?
Yes, Hubble is not sensitive to IR and has a tube it resides in.
JWST cannot allow sunlight to touch anything this side of the Sun shield or it would get hot and then send IR onto the mirrors, warming them.

JWST can basically look 90° sideways from the Sun. From there it can only tilt 5° toward the Sun but can tilt 45° away from the Sun. The difference is due to the particular shape of the Sun shield.

And, no, it cannot look at Earth, Earth is too close to the Sun. They are always in a straight line, Sun, Earth, JWST. Even the Moon, as it orbits the Earth is too close to the Sun.
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WST can do this because it's equipped with spectrographs that spread white light into infrared rainbows of color.
Yes. What the HST does with visible light, the JWST does with IR. [The visible spectrum gives us colors; the IR spectrum is in bands, since color is a human visible light experience.]

There is some overlap between visible and IR with both telescopes.
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