James Webb

[HappySkeptic]

I'm most interested in observations of extra-solar planets.  However, even Webb isn't going to be able to see earth-like planets or measure their atmosphere.  That will likely require LUVOIR or a set of space-based telescopes doing interferometry.

depends on what you mean by “see”.   dozens of exoplanets have already been directly imaged from the ground.

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There are also several additional Hubble scale optical snd near optical space telescopes in the works, scheduled to be launched in the next 5 years.   They either cover different wave length from hubble, or capable of scanning the sky much more quickly than hubble so as to be able to provide full coverage of the sky at bear hubble resolutions.    These are Less flashy than JWST, but perhaps promise work of comparable importance.

habitable exoplanets can only be "seen" through occultation of their star.  This drastically limits the number we will find, and the signal is nowhere nearly large enough for us to measure atmospheres.

Sure, we can directly see some gas giants, especially when around dim stars, but they aren't habitable.  We are able to measure some large-planet atmospheres as well. Perhaps Webb will be able to measure some Titan-like atmospheres, because it is so thick.

To really get to see habitable planets directly, and do atmospheric measurements, we would need something more than what has been proposed.  I saw an idea for an occulting disk, thousands of kilometers from a hubble-size telescope.  That should provide the ability to cut out the starlight and see and measure planets.  I've also seen ideas for multi-telescope interferometry - though I'm not sure those will get the signal-to-noise with only internal star occultation.