The opposite day I ran throughout this photograph of Saturn’s moon Titan taken by the James Webb Area Telescope (JWST).
If JWST can see Titan with this type of decision, how properly may it see Pluto or different planets? On this submit I’ll do some back-of-the-envelope calculations, solely contemplating the obvious dimension of objects, ignoring different elements resembling how vivid an object is.
The obvious dimension of an object of radius r at a distance d is proportional to (r/d)². For extra particulars, see the submit Solid angle of a star.
After all the JWST isn’t situated on Earth, however JWST is near Earth relative to the space to Titan.
Titan is about 1.4 × 1012 meters from right here, and has a radius of about 2.6 × 106 m. Pluto is about 6 × 1012 m away, and has a radius of 1.2 × 106 m. So the obvious dimension of Pluto could be round 90 occasions smaller than the obvious dimension of Titan. Based mostly on solely the elements thought of right here, JWST may take an honest photograph of Pluto, however it might be decrease decision than the photograph of Titan above, and much decrease decision than the images taken by New Horizons.
May JWST {photograph} an exoplanet? There are two confirmed exoplanets are orbiting Proxima Centauri 4 × 1016 m away. The bigger of those has a mass barely bigger than Earth, and presumably has a radius about equal to that of Earth, 6 × 106 m. Its obvious dimension could be 150 million occasions smaller than Titan.
So no, it might not be doable for JWST to {photograph} an expolanet.