Venus Pops a Slim Crescent, Revealing Its True Phase Geometry

Venus is slipping toward inferior conjunction (Oct. 24), its disk shrinking from about 36% to 32% illuminated while its apparent size grows. The planet peaks in brightness in mid‑September (around magnitude -4.8 on Sept. 18) as the thin crescent becomes most conspicuous in small telescopes. After that, it fades into the sunset glare, so observers—especially in mid‑northern latitudes—should look low in the west-southwest just after sunset, using a telescope or binoculars to glimpse the phase. This is a classic demonstration of solar system geometry, echoing Galileo’s early observations that confirmed the heliocentric model; meanwhile, the August 15 greatest elongation (~46 degrees) precedes October’s closer approach to the Sun.