50 Fun Facts About Venus

Where does Venus rank in distance from the Sun?

It orbits between Mercury and Earth and comes closer to Earth than any other planet.

Which planet is the hottest in the Solar System?

Its runaway greenhouse effect keeps the surface at about 464 °C, hotter than Mercury despite being twice as far from the Sun.

Roughly what is the surface temperature of Venus?

That is hot enough to melt lead, and it barely varies between the equator and the poles.

The atmospheric pressure at the surface of Venus is roughly how many times Earth's at sea level?

That is like being nearly a kilometre under the ocean; the lowest air layer behaves as a supercritical fluid.

Venus's atmosphere is made almost entirely of which gas?

About 96.5% CO2 and 3.5% nitrogen, with clouds of sulphuric acid on top.

The clouds that cover Venus are made of what?

They reflect so much sunlight that Venus is the brightest natural point of light in our sky.

Venus rotates in the opposite direction to most planets. What is this called?

Seen from its surface, if you could see through the clouds, the Sun would rise in the west.

On Venus, which is longer: its day or its year?

A sidereal day of 243 Earth days beats a year of 224.7 Earth days.

Which direction would the Sun appear to rise from the surface of Venus?

The retrograde spin flips sunrise, though the opaque clouds mean nobody on the surface could watch it.

Venus is often called Earth's 'twin' or 'sister' because of what?

Its diameter is only about 640 km less than Earth's and its mass is 81.5% of Earth's.

How many natural moons does Venus have?

Cassini claimed to see a moon called Neith in the 17th century, but it was never real.

What name was given to the nonexistent moon of Venus that Cassini reported in the 17th century?

Sightings continued for two centuries; most were stars in the background.

What is it called when Venus's cloud-top winds circle the planet in four days, far faster than it spins?

The winds reach 300 km/h, about 60 times the speed of the surface below.

What is the name of the highest mountain range on Venus?

It rises about 11 km, higher than Everest, on the northern highland Ishtar Terra.

Venus's highest mountains, a rare feature not named for a woman, honour which physicist?

Alpha, Beta and Ovda Regio are the other exceptions, all named before the IAU rules were set.

Most surface features on Venus are named after what?

Craters carry names like Cleopatra and Sacajawea; the two continents are Ishtar and Aphrodite.

The northern highland 'continent' of Venus, about the size of Australia, is named after which goddess?

The southern continent, Aphrodite Terra, is larger, roughly the size of South America.

How many volcanoes larger than 100 km across does Venus have?

Earth has just one volcanic complex that big, the Big Island of Hawaii.

Why does Venus have no impact craters smaller than about 3 km across?

Anything under about 50 m across fragments and burns before reaching the ground.

How old is the surface of Venus estimated to be?

Its few craters suggest the whole surface was resurfaced by volcanism relatively recently.

What is Venus's maximum apparent magnitude, making it brighter than any star or planet?

It is bright enough to see in daylight, and it is the most commonly misreported 'UFO'.

How often does Venus 'overtake' Earth, switching between Evening Star and Morning Star?

That is its synodic period, about 1.6 years.

What did the ancient Greeks call Venus as morning star and evening star, thinking them two objects?

Pliny credited Pythagoras with realising they were the same body.

The Romans called the morning aspect of Venus by what name, literally 'Light-Bringer'?

The evening aspect was Vesper; both are direct translations of the Greek names.

Whose 1610 discovery that Venus shows phases helped demolish the Earth-centred model?

A full set of phases is impossible if Venus circles the Earth rather than the Sun.

Who observed the first known transit of Venus in 1639, having predicted it himself?

He used it to estimate the size of the astronomical unit, the whole point of watching transits.

Captain Cook sailed to Tahiti in 1768 to record a transit of Venus. What did the voyage lead to?

Only seven Venus transits have ever been observed.

When is the next transit of Venus?

The last pair were in 2004 and 2012; they come in pairs eight years apart, then a gap of over a century.

Who discovered that Venus has an atmosphere, in 1761?

He noticed a glowing ring around the planet during a transit.

Which was the first successful interplanetary mission, flying past Venus in December 1962?

The Soviet Venera 1 had tried a year earlier but lost contact on the way.

Which spacecraft made the first soft landing on another planet, on Venus in December 1970?

It transmitted from the surface for about 20 minutes and measured a temperature of roughly 475 °C.

For roughly how long did the first Venus lander transmit data from the surface?

It probably bounced onto its side, leaving its antenna pointed away from Earth, and the faint signals were only found on tape weeks later.

Which nation's landers sent the first pictures from the surface of Venus, in 1975?

The images were black and white; Venera 13 and 14 sent colour-filter pictures in 1982.

Which NASA spacecraft mapped the surface of Venus with radar between 1990 and 1994?

Its maps still underpin most of what we know about the planet's geology.

The Soviet Vega missions of 1985 achieved what first at Venus?

The inflatable aerobots were the first extraterrestrial aircraft of any kind.

Which country's Akatsuki probe orbited Venus from 2015 to 2024?

It spotted a huge stationary bow-shaped wave in the atmosphere in 2015.

Which gas, tentatively detected in 2020, sparked speculation about life in Venus's clouds?

Later analyses blamed sulphur dioxide or found no absorption line at all.

What kinds of craft are VERITAS and DAVINCI, the Venus missions NASA selected in 2021?

India's ISRO has also planned a Venus orbiter, Shukrayaan, targeted for 2028.

At what altitude above Venus are pressure and temperature similar to Earth's?

Carl Sagan first suggested in 1967 that microbes might survive in the cooler cloud layers.

Venus is named after the Roman goddess of what?

She descends from Greek Aphrodite and, before her, Sumerian Inanna, all linked to the planet.

Which day of the week is associated with Venus and its goddesses?

English Friday comes from the Germanic goddess Frigg, equated with Venus; French vendredi keeps the Roman name.

What did the Old Babylonians call Venus, a name meaning 'divine lady, illumination of heaven'?

It was later called Dilbat, and the goddess Inanna's movements in myth may track the planet's.

The Maya called Venus 'the Great Star'. Which national flag is said to depict Venus as a lone star?

The Maya tracked its cycles in the Dresden Codex.

The astronomical symbol for Venus, a circle over a small cross, is now widely used to mean what?

Alchemists used it for copper; biology borrowed it as the female gender symbol.

Which metal did Western alchemists represent with the Venus symbol?

Polished copper made ancient mirrors, so the symbol is sometimes read as a hand mirror.

What poetic Old English name, meaning 'ray of light', was given to Venus?

Tolkien borrowed the word for his mariner Eärendil, who carries a star across the sky.

Venus's axial tilt is less than 3 degrees. What effect does this have?

Combined with the thick atmosphere it makes the whole surface nearly the same temperature everywhere.

What is the name of Venus's quasi-satellite, an asteroid that shares its orbit?

Venus has no true moons, though 524522 Zoozve and two temporary trojans accompany it around the Sun.

Which 1974 probe used Venus for the first interplanetary gravity assist, bending its path to Mercury?

Its ultraviolet photos of the clouds revealed the extraordinarily high wind speeds in the Venusian atmosphere.

Pliny the Elder credited which thinker with realising the morning and evening 'stars' were one object?

The Greeks had called them Phosphorus and Hesperus; Ptolemy later placed Venus between the Sun and Earth in the Almagest.