Venus, the second planet from the sun, is an oddity in many ways. Here are the top 10 weirdest things about this scorching hot planet that some believe might host microbial life in its impenetrable clouds.
There are more volcanoes on Venus than on any other planet in the solar system. Astronomers know of more than 1,600 volcanoes on its surface, but there are likely many more too small for us to see. Scientists think most of these are dormant, though a handful may still be active.
Where days outlast years
Of all the solar system's planets, Venus is the closest to a twin of Earth. The two bodies are nearly of equal size, and Venus' composition is largely the same as Earth's. The orbit of Venus is also the closest to Earth's of any solar system planet. Both worlds have relatively young surfaces, and both have thick atmospheres with clouds. However, it's worth nothing that Venus' clouds are mostly made of poisonous sulfuric acid. In spite of that, in 2020, astronomers detected a chemical called phosphine in Venus's clouds, which on Earth is usually produced by microbes. The widely publicized study seemed to suggest that the hot and hellish planet might host life in the end. Other scientists have since than disputed this theory and offered other explanations.
Venus is scorching hot
Because the bulk of its atmosphere is made of carbon dioxide, an extreme greenhouse effect is warming the surface of Venus. Temperatures there can reach a scorching 870 degrees Fahrenheit (470 degrees Celsius).
"The surface is hot enough to melt lead due to its runaway greenhouse atmosphere," Sue Smrekar, a scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., said in a statement.
The air pressure on the surface of Venus is extreme — about 90 times higher than the pressure at sea level here on Earth. In other words, the pressure on Venus is about the same as the water pressure on Earth about half a mile (1 km) under the ocean.
We see Venus cross the sun
Venus is rare among the planets in that we can see it cross in front of the sun. Only Venus and Mercury do this from the vantage point of Earth. Venus transits occur rarely, with pairs separated by eight years coming around less than once a century. The last pair took place in 2004 and 2012. But that's it for our generation. The next Venus transit will happen in 2117. There have only been eight Venus transits that humans could observe since the invention of the telescope in 1610.
Our brightest planet
While Venus is not nearly the largest planet of the solar system, its proximity to Earth makes it the brightest of the planets in the sky. It also qualifies as the second-brightest object in the nighttime sky, after only the moon.
In fact, Venus can appear so bright that a pilot aboard an Air Canada flight in January 2011 actually mistook the dazzling planet for an oncoming aircraft. The pilot sent his plane into an emergency dive to avoid a midair collision with what investigators later determined was Venus, which was still safely millions of miles away, according to Canadian air transportation officials.
Mystery of the ancients
Venus has been a target of observation for millennia.
The ancient Babylonians tracked its wanderings through the sky in records that date as far back as 1600 BC. The Greek mathematician Pythagoras was the first to discover that the brightest stars in the morning and evening sky were in fact the same object, Venus.
Whoosh! A windy planet
Winds swipe across Venus at super-fast speeds that can reach 450 miles an hour (724 kph) in its middle cloud layer. These Venusian winds are faster than the speediest tornado on Earth.
Venus has phases.
Because Venus orbits the sun within Earth's orbit, the planet appears to have phases like the moon. When Venus is on the opposite side of the sun, it is in full phase, while it appears in new phase when it is between the Earth and the sun.
The first person to witness these phases was Italian astronomer Galileo Galilei in 1610.
Learn more about Venus on this interactive NASA website.