The Planet Where a Day Lasts Longer Than a Year
“Hail Earendel, brightest of angels, over Middle-Earth, sent unto men.” This line was written about 1,200 years ago, by the English poet Cynewulf, in praise of the planet Venus. Cynewulf’s poem inspired J.R.R. Tolkien to create middle-earth and the hero Earendil (he’s in the Silmarillion, not the Lord of the Rings). “Earendel” means “wanderer” as does the Greek word “planet” because Venus, like other planets, appears to follow a wandering, drunken course through our skies over the year, rather than a straight path.
Cynewulf was inspired by Venus because it’s the brightest object in the night sky, aside from the moon, and it always appears low in the sky around sunrise and sunset because its orbit is relatively close to the Earth’s. All the ancient cultures who watched the sky singled Venus out for its beauty; go see for yourself as it’s the easiest “star” to see through urban light pollution.
Global radar view of Venus (without the clouds) from Magellan between 1990 and 1994.
The ancients thought the morning star and evening star were different stars—Vesper and Lucifer (“light-bearer”) to the Romans. To the Maya of Central America, it was Kukulkan, the feathered serpent-god, and they tracked its risings and settings with their elaborate astronomical calendar. Now we call this star Venus, the Roman goddess of love and beauty (and now you know why they’re called “venereal diseases”).
Venus is the second planet from our sun (Earth being the third); it takes sunlight six minutes to reach Venus and eight minutes to get to Earth. Both planets orbit in the sun’s “habitable zone” (not too close, not too far). Venus might have hosted life millions of years ago, but not now; the Greenhouse Effect, the same climate-changing process facing Earth, has rendered it drastically uninhabitable. Venus’ atmosphere is mostly carbon dioxide. The planet probably had water once, which boiled away. Now, Venus is the hottest world in our solar system, with surface temperatures hot enough to melt lead (and any probes we send down) and an atmosphere so thick that the pressure at the surface is 90 times higher than on Earth. It’s bone dry, with powerful winds, volcanoes, and sulfuric acid rain!
Size comparison of Venus and Earth.
Venus is Earth’s twin sister in size and composition with a molten iron core, a few thousand kilometers in diameter, and a rocky “mantle”. Unlike Earth, Venus has no global magnetic field, probably because it doesn’t spin fast enough. Venus rotates only once in 243 Earth days.
And, it rotates east to west, the opposite of Earth. So on Venus, the sun rises in the west and sets in the east. Its year is 225 Earth-days long which means that one day lasts longer than a year! But that wouldn’t make much difference to the Venusians because Venus has no seasons; it’s not tilted relative to the sun like Earth. And Venus has mainly one kind of weather; its cloud-level atmosphere rotates opposite the planet’s spin, ripping around Venus every four Earth days with hurricane-force winds.
Venus (yellow) completes one orbit of the Sun (center) for every 0.62 orbits of Earth (blue).
Almost the entire surface is solidified lava, 300-500 million years old, and dotted with 1,000s of volcanoes. It has two big highland areas much like continents: Ishtar Terra near the North Pole and Aphrodite Terra on the Equator. The highest mountain, Maxwell Montes, comparable to Everest, sits on the eastern edge of Ishtar Terra.
The first spaceship to Venus was Mariner 2 in 1962. More than 20 missions have visited since, including the Soviet probe Venera 7, the first human machine to land on another world, which sent us 23 minutes of data before melting. The European Space Agency’s Venus Express arrived at Venus in 2006 and is now studying the atmosphere.
Venus has always inspired wonder, awe, and fantasy in watchers. Early sci-fi pictured it replete with large-breasted barbarian women wielding swords. But, although we now know it’s unimaginable hell below those highly reflective clouds, it’s still a paragon of beauty in our skies. So, take a look and think of Cynewulf 1,200 years ago, calling it an angel.
“We are just an advanced breed of monkeys on a minor planet of a very average star. But we can understand the Universe. That makes us something very special.” – Stephen Hawking
“Maybe this world is another planet’s hell.” – Aldous Huxley
“Any planet is 'Earth' to those that live on it.” – Isaac Asimov
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