Science · 6 pages · 12 min

How a telescope gathers light rather than magnifying only

A telescope first collects light, and magnification only spends what was collected.

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From the opening

A telescope makes faint things visible mainly by gathering more light than a pupil can, using a large mirror or lens as a bucket for photons. Magnification then spreads that collected light over a larger angle so an eye or a camera can examine it. The opening covers why aperture sets the light, what magnification does afterward, and how the air limits sharpness.

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Inside

Why aperture sets the light
What magnification does afterward
How the air limits sharpness
Why a camera changes the bargain
Where the idea stops applying
A distinction worth keeping

Sources

Aperture as a telescope's light-collecting area
The separation of magnification from resolution

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How a telescope gathers light rather than magnifying only

From the opening

Inside

Sources

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