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Venus completes one orbit around the Sun in 225 Earth days, traveling an average of 108 million km (67 million mi) along a nearly circular path. Unlike most planets, Venus rotates on its axis in a retrograde direction—clockwise from Earth’s perspective. Its rotation is so sluggish that one Venusian day lasts 243 Earth days.
Because of its proximity to Earth, Venus shines almost as bright as the Moon. It alternates between being the “evening star” and the “morning star” every 584 days, depending on whether it has caught up with or passed Earth in its orbit. At its closest approach—about 42 million km (26 million mi)—its thick cloud cover makes it exceptionally luminous.
A transit occurs when Venus passes directly between the Sun and Earth. Transits come in pairs separated by eight years, a pattern first recorded with the advent of the telescope in 1631 and 1639. The most recent pair happened in 2004 and 2012, with the next expected in 2117.
Venus’s atmosphere is a dense envelope of water vapor and sulfuric acid clouds, producing crushing surface pressure and a greenhouse effect that keeps temperatures around 470 °C (880 °F). The planet’s surface is marked by craters, extinct volcanoes, and large shield‑like formations that would resemble continents if oceans were present. Day‑night temperature variations are minimal due to the insulating cloud layer.
Learn more at NASA – Venus Overview.
