Next: Resolving Power of a Telescope
The larger the diameter of a telescope mirror, the more light it collects. Similarly, the larger the mirror, the less time it takes it to collect a given amount of light. This second relation can be expressed as:
For example, the diameter of the Hampden-Sydney telescope is 0.4 m. The diameter of the Keck Telescope is 10 m. Thus the ratio of the collection times for the Keck and the H-SC telescopes is:
Thus it would take 5.76 seconds for the Keck Telescope to collect the light that the Hampden-Sydney telescope collects in one hour. (5.76 seconds/1.0 hour) = 1.6 X 10-3.
Next: Resolving Power of a Telescope