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shangtsail
2008-Apr-27, 10:51 PM
What I can think of is that a small telescope does not collect enough light to produce a bright, magnified image. To raise sensitivity and thus observe faint objects in detail, a larger light-gathering area is necessary.

How do large telescopes help improve resolution?

Thank you.

Neverfly
2008-Apr-27, 11:02 PM
THis might be better off in Equipment and Observing forum...

But.. umm.. Didn't you just answer your own question?
:whistle:

Notice you're at three posts- Welcome to BAUT:)
In the About BAUT forum you will notice a fridge with Dr pepper in it.
Do not drink them.
They are mine.

parejkoj
2008-Apr-27, 11:10 PM
Welcome to BAUT!

Two things: the amount of light collected goes up with the area of the telescope, and thus the radius squared. So a 2 meter telescope collects four times as much light as a 1 meter telescope, and the Keck (10m) telescope collectes 100 times as much light as the 1 meter.

The other reason is that resolution is proportional to (observed wavelength)/(aperture diameter), so when observing in visible light, the 10 meter telescope can resolve objects 10 times smaller than the 1 meter.

Also, bigger telescopes are cooler.

shangtsail
2008-Apr-27, 11:11 PM
Thanks, parejkoj!!

Amber Robot
2008-Apr-28, 12:02 AM
The other reason is that resolution is proportional to (observed wavelength)/(aperture diameter), so when observing in visible light, the 10 meter telescope can resolve objects 10 times smaller than the 1 meter.


Although this is technically true, the atmosphere does limit your resolution. A larger telescope, unaided, will not improve resolution, although it does increase collecting area, as mentioned. Pretty much all large telescopes in the future will need to incorporate adaptive optics (AO) in order to achieve their diffraction limit. Many currently operating telescopes use AO as well.