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ApertureBuy the right telescope, not the biggest one

How much aperture does it take?

Seeing Venus through a telescope

A brilliant white crescent, like a tiny moon. No surface detail — the cloud deck is featureless in visible light — but the phase is unmistakable in almost anything.

Through three telescopes, under a suburban sky

Each circle is the true field of a 10 mm eyepiece. Same target, same sky; only the aperture changes.

70 mm · 49×

Detailed

130 mm · 91×

Detailed

250 mm · 175×

Detailed

The aperture it takes, by sky

Venus does not care about light pollution: it is bright, and the air, not the sky glow, sets the limit.

LevelMilky Way blazingMilky Way, barelyNo Milky Way
Detectable10 mm10 mm10 mm
Recognisable40 mm40 mm40 mm
Detailed60 mm60 mm60 mm

When to look

Visible for months at a time as a morning or evening star.