How far back in cosmic history has the JWST pushed the observation of quenched galaxies?

Answer

To when the universe was barely a few hundred million years old.

Discoveries by the James Webb Space Telescope have identified galaxies that had already died when the universe was only a few hundred million years old.

How far back in cosmic history has the JWST pushed the observation of quenched galaxies?

#Videos

NASA finds dead spiral galaxy - YouTube

JWST Finds a Bizarre Galaxy In Early Universe That Appears Dead

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