As the brightest planet in the sky, Venus has been known to astronomers since ancient times. In this article, we’ll tell you more about this fascinating planet — from its discovery history to the color of its surface.
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- Planet type: terrestrial
- Radius: 6051.8 km (3760.4 miles)
- Mass: 4.867×10²⁴ kg
- Aphelion: 108.939 million km (67.691 million miles)
- Perihelion: 107.476 million km (66.782 million miles)
- Average distance from the Earth: 261 million km — 40 million km (149 million miles — 25 million miles)
- Surface temperature: 438 °C to 482 °C (820 °F — 900 °F)
- Solar day length: 116.75 Earth days
- Sidereal day length: 243.022 Earth days
- Year length: 224.701 Earth days
- Age: 4.503 billion years
- Named after: the Roman goddess of love and beauty
When was Venus discovered?
The exact date of Venus’ discovery is unknown; as this bright planet can be easily seen with the unaided eye, it was observed by ancient astronomers from different civilizations since the dawn of time. Thus, we don’t know for sure who discovered Venus; however, Nicolaus Copernicus and Galileo Galilei are credited with the classification of Venus as a planet. The latter carried out the first accurate observation of Venus in 1610: Galileo viewed the planet through a telescope and discovered its phases, which are similar to the lunar ones. This discovery proved the Copernican theory that planets orbited the Sun and not vice versa.
How big is Venus?
Is Venus bigger than the Earth?
With a diameter of 12,104 km (7,521 miles), this second closest planet to the Sun is slightly smaller than the Earth. Also, the mass of Venus is about 81% that of our planet.
Venus’ orbit and rotation
How long is a day on Venus?
The rotation of Venus is very slow: it takes about 243 Earth days to spin around just once.
How long is a year on Venus?
Ironically, one Venusian day is longer than one Venusian year as it takes Venus 225 Earth days to complete an orbit around the Sun.
How far away is Venus?
How far is Venus from the Sun?
Venus is the second planet from the Sun; its distance from our star is just over 70% the distance between Earth and the Sun. As Venus’ elliptical orbit is the least eccentric of any of the planets, there is no significant difference between its closest (107.4 million km) and farthest (108.9 million km) points from the Sun (66.7 million miles to 67.6 million miles). The average distance is 108.2 million km (67.2 million miles).
How far is Venus from the Earth?
Venus is the closest planet to the Earth, although the distance between the planets constantly varies as they move in their elliptical orbits around the Sun. At its closest approach to the Earth, which happens once every 584 days, the distance between Venus and our planet can be about 40 million km (25 million miles).
How long does it take to get to Venus?
It took NASA’s Mariner 2 sent to Venus in 1962, and Venera 7 of the Soviet Union launched in 1970 less than four months to reach the planet.
Missions to Venus
As thick clouds hide the Venusian surface, for a very long time people believed that Venus was similar to the Earth. This close planet has always been interesting for scientists and astronomers: over 40 spacecraft have explored Venus. Its proximity to our planet will always make Venus a target for future studies and journeys.
What is Venus made of?
Unfortunately, little information is available about the internal structure of Venus.
Formation of Venus
Venus formed together with the other Solar System planets. About 4.5 billion years ago, a giant cloud of interstellar gas and dust collapsed under its own gravity and flattened into a protoplanetary disk. Venus and the other rocky planets formed in the inner part of this disk, while the gas giants settled in the outer regions of the young Solar System.
Due to the similarity in size and mass between Venus and the Earth, scientists believe that the planets share a similar interior. Venus is likely to have a crust, a rocky mantle, and a liquid core. However, the core might also be solid or even might not exist at all.
The gaseous Venusian atmosphere was initially discovered in 1761 by the Russian polymath Mikhail Lomonosov. Observing the transit of Venus across the solar disk, Lomonosov spotted a light ring around the planet’s disk. He correctly assumed that this phenomenon might be caused by the refraction of the Sun’s rays in the thick Venusian atmosphere.
The atmosphere of Venus consists of 96.5% carbon dioxide, 3.5% nitrogen, and traces of other gases. Thick clouds composed of sulfuric acid and water vapor cover the planet’s surface and reflect about 70% of the sunlight that reaches Venus: that’s why this planet is so bright.
When can you see Venus?
As Venus is closer to the Sun than the Earth, the Sun’s glare outshines the planet most of the time. Nevertheless, it becomes visible for terrestrial observers at certain periods of time. The best time to see Venus is when the planet reaches its greatest elongation or, in other words, greatest separation from the Sun, as seen from the Earth.
The greatest elongations of Venus take place roughly every 9 months. The greatest western elongation is also called the morning one, as, during this period, Venus shines brightly in the predawn sky — hence the name “morning star”. And vice versa, the eastern elongation is referred to as the evening one as Venus appears in the sky after sundown.
October 28: Venus at dichotomy
On October 28, 2021, at 14:28 GMT (10:28 a.m. EDT), Venus will reach dichotomy or half phase, shining with an apparent magnitude of -4.4. Through a telescope, Venus’ planetary disk will look half-illuminated, just like the Moon during at first or last quarter. As theoretical and observed dichotomy can vary by several days, better start your observations in advance.
October 29: Venus at greatest elongation
On October 29, 2021, at 14:57 GMT (10:57 a.m. EDT), Venus will reach its greatest separation from the Sun in its 2021–2022 evening apparition, standing 47° from our star. Although the planet will stay low above the horizon, it still will be a decent target for observations, shining with a magnitude of -4.4. Just find an unobstructed horizon (a beach is a perfect option).
How many moons does Venus have?
Actually, Venus has no moons at all! Venus and Mercury are the only planets of the Solar System that don’t have any natural satellites orbiting them. Scientists suggest that Venus might once have had a moon formed as a result of a collision. Later, another collision destroyed this satellite.
How hot is Venus?
The thick Venusian atmosphere trapping heat causes surface temperatures higher than 470 °C (878 °F). That is the reason why Venus is hotter than Mercury, the closest planet to the Sun.
What color is Venus?
Venus appears white and yellow with some reddish and brown spots. The reason is that it’s covered with a thick carbon dioxide atmosphere and sulphuric acid clouds.
Is Venus the morning star?
It’s interesting that ancient skygazers took Venus for two separate sky objects: the Morning Star and the Evening Star (or Phosphorus and Hesperus to the Greeks and Lucifer and Vesper to the Romans).
We hope that you enjoyed reading this article and learned something new about Venus from it. Please share it with your friends on social media and let us know if you’d like to learn more about other sky objects! And watch our educational cartoon with fun facts about Venus.
We wish you clear skies and happy observations!