Overcoming the Diffraction Limit

[astronut]

The diffraction limit of a telescope is limited by its aperture and the quality of its optics. Does anyone know how large observatories overcome this?

Does the fact that these large observatories are generally on mountain tops and hence have less atmospheric interference help in this situation?

Does the atmosphere impact on the diffraction limit?

[CanisMajorTom]

I'm not really sure I understand the question. Though I think large telescopes would handle this the same as small telescopes. Larger telecopes would have a better difffraction limit.

Welcome to the site mate.

[RSW]

Larger telescopes have a better diffraction limit. Meaning they cope much better with this issue. So the large the aperture, the better.

[AstroTasmania]

Telescope optics that are diffraction limited are optically perfect to resolve at the Dawes limit. Atmosphere is the limiting factor, it does effect larger aperture scopes to a greater extent in poor seeing.

This optical perfection is restricted or 'limited' by the atmospheric seeing conditions. This is one of the main reasons that big observatories are on mountain tops, so that they are looking through the least thickness of atmosphere, especially the lower man made polluted part.

If the scope was used in a vacuum, it would have perfect images all the time and work to its full potential, providing its optics performed to the Dawes limit.

Oh for Clear skies...

[Radar]

I think the moon will become a prime spot of a large telescope one day because of those reasons.

[CanisMajorTom]

Atmosphere is the limiting factor, it does effect larger aperture scopes to a greater extent in poor seeing.


Who has heard of adaptive optics? Under the mirrors of the large telescopes these days, there are literally thousands of actuators propping the mirror up in certain places to overcome atmospheric turbulance. The results are amazing.