very large telescopes

 

resolution limitation and breakthrough

Improvement in angular resolution at optical wavelengths. The development of adaptive optics has permitted diffraction-limited observations from ground-based observatories since 1990, largely eliminating the effects of the atmosphere. 

The dashed line shows the theoretical diffraction-limited resolution for the telescope. The solid line shows the seeing limit imposed by the atmosphere. Improvements were obtained by going to very good seeing sites. The resolution of the Hubble Space Telescope is shown,

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