Venus is the second planet from the Sun and also the hottest planet in the solar system. Planet Venus rotates opposite to most other planets. It is the brightest planet and can be seen even in daylight if you know where to look.
When Venus is west of the Sun, it rises before the Sun therefore known as the Morning star and when it is east of the Sun it shines in the evening just after the Sunset and is called Evening star.
Planet Venus has a very dense atmosphere and doesn’t have any moons.
One day on Venus is 243 Earth days which is longest of any planet.
A little History
Venus is one of the five planets that are visible with a naked eye: Mercury, Venus, Jupiter, Mars and Saturn. Out of this five Venus is the brightest. So, it’s safe to say that the planet has been visible to humans since the beginning of humanity.
Ancient astronomers didn’t really know what Venus was, some thought of it as a star.
Copernicus was the first person to recognise Venus as a planet in his solar system model.
Galileo was the first person to observe the planet through a telescope. He observed the transit of Venus around the Sun which confirmed that Venus was a planet and was orbiting the Sun and not the Earth.
What is the planet Venus named after?
Out of all the five planets that were visible to ancient Roman’s, Venus was the brightest and the most beautiful planet. That is why they named it after their goddess of love and beauty. Venus is also the only planet named after a female.
Visibility from Earth
Venus is visible from Earth at a very decent majority of times either before sunrise or after sunset.
Venus is always brighter than all the planets and stars (except the Sun) when seen from Earth.
Distance from the Sun
Venus is 67,237,910 miles or 108,208,930 km from the Sun. Venuses closest approach to the Sun is 66,782,000 miles or 107,476,000 km and the farthest approach is 67,693,000 miles or 108,942,000 km.
It takes sunlight 6 minutes to the planet.
Venus has the most circular orbit of all the planets in the solar system.
Venus is also the closest planet to Earth with the closest point occurring at 38 million km.
Size of Venus
Venus is the six biggest planet in the solar system and about 1.8 times larger than Mars.
Venus is called Earths sister because they are very similar in size and structure. Earth is slightly bigger than Venus. The Diameter of Venus is 12,103.6 km only 638 km less than Earth and mass is 81% of Earth.
Because of their similar sizes, it was thought that Venus was Earth-like with water and life but Venus is actually the most inhospitable planet in the solar system.
How hot is Venus?
Very hot, Venus is the hottest planet in the solar system hotter than the closest planet to the Sun, Mercury. The mean temperature on Venus is 465 degree Celsius.
Venus has a very dense atmosphere which prevents the Sun’s heat from escaping back to space causing an extreme greenhouse effect. We discussed that Mercury is very strange when it comes to temperature variations but the temperature on Venus barely changes.
The temperature on Venus is hot enough to melt lead.
There is no water on the surface of Venus because of the extreme heat. The astronomers believe that Venus was previously an Earth-like planet covered with oceans but the water evaporated because it is too close to the Sun turning it into barren volcanic land.
How long is the day on Venus?
Venus is a very slow planet. It takes Venus 243 Earth days to make one full rotation on its axis and 225 Earth days to make one full orbit around the Sun.
Wait!! Does that mean that a day on Venus is longer than the year? Yes, it is…
Venus has the longest day of all the planets.
On Venus, one day-night cycle takes 117 Earth days because Venus rotates in the direction opposite of its orbital revolution around the Sun.
All planets rotate clockwise but Venus rotates anticlockwise, it means that on Venus the Sun rises in the west and sets in the east.
Venus orbit around the Sun is almost circular, unlike other planets who have an elliptical or oval-shaped orbit.
Transit of Venus
A transit of Venus occurs when it passes directly between Earth and the Sun, which appears as a tiny disk.
It occurs in cycles of 243 years with the most recent pair of transits separated by 8 years. The most recent transit occurred in 2004 and 2012.
The next pair of transits will appear in the December 2117 and December 2125.
English astronomer Jeremiah Horrocks was the first person to successfully record the transit of Venus in 1639 and also the first to discover the pattern.
Atmosphere and climate
Venus has a very dense atmosphere composed of 96% carbon dioxide (CO2), nitrogen (N2), sulphur dioxide (SO2) and other gases. The pressure at the surface is 92 times that of the Earth, that is equivalent to the pressure at depth of 1 km under Earths ocean.
Since most of the Venus atmosphere is made of carbon dioxide it produces the strongest greenhouse effect in the solar system with the surface temperature reaching 465 degree Celsius or 735 kelvins making it hotter than Mercury.
Astronomers think that the Venus was similar to Earth with water but all the water was evaporated creating an immense greenhouse effect.
There is speculation that life may exist in upper cloud layers of Venus about 50 km from the surface.
Surface of Venus
To human eyes, Venus will appear yellowish white from space. The surface is more reddish brown.
Most of the Venus is made of Volcanic Plains.
Venus has the highest number of volcanos in the solar system and many of them are still active. Highest mountain range on Venus is Maxwell which is about 540 miles (870 km) long and 7 miles (11.3 km) high.
Venus has two big continents, Ishtar Terra lies to the north, covering an area approximately the size of Australia, while the Africa-sized Aphrodite Terra lies just south of the equator.
Venus doesn’t have many small craters like Mercury since most small meteoroids burn up in the atmosphere.
Both Venus and Earth have a very similar internal structure.
They both have a core (3,200 km in radius), mantle and a crust. Although Venus core is thought to be a lot stronger than previously imagined.
Despite having similar size and internal structure, the Venusian magnetic field is much weaker than Earths. This might be because of the slow spin of Venus and the core may not spin fast enough to create a magnetic field.
Sorry! No moons. Jupiter has got 79 moons, maybe you should check those out.
Venus is one of the most explored planet in the solar system with over 40 attempts already made to explore the planet.
First attempt to reach the planet was made by the Soviet’s Venera programme which started in 1961.
Venera 1, launched in 1961 was the first spacecraft to fly past Venus. However, no data was returned from the spacecraft because of radio failure.
Nasa’s Mariner 2 was the first successful mission to Venus and Venera 7 was the first spacecraft to land on Venus.
Here is the list of all the successful missions to Venus:
- Mariner 2
Mariner 2 was the first spacecraft to make a fly-by of planet Venus. The spacecraft discovered ground temperatures as high as 460 degrees Celsius. Existence of dense clouds was also one of the discoveries.
- Venera 4
Successfully entered the planet’s atmosphere. Discovered that the planet’s atmosphere is mostly made of Carbon dioxide and was lot a denser than expected. It also detected a weak magnetic field.
- Mariner 5
The spacecraft was originally designed as a backup for Mariner 4 mission to Mars. But after Mariner 4 success it was modified for Venus mission.
Data from the mission helped understand the temperature and atmosphere of the planet better than is predecessor Mariner 2.
- Venera 5
Venera 5 was very similar to Venera 4 but was a little stronger. It entered the Venusian atmosphere on May 16, 1969, and lasted for 53 minutes.
It confirmed the discoveries made by Venera 2.
- Venera 6
Again, very similar to Venera 5, it arrived just a day after Venera 5 and lasted for 51 minutes.
- Venera 7
When it landed on the Venusian surface on 15 December 1970, it became the first spacecraft to land on another planet.
The probe sent the data for 20 minutes from the surface. It reported surface temperatures of 475 degree Celsius and atmospheric pressure 90 times greater than Earth’s.
- Venera 8
Second lander mission after Venera 7, it landed on the Venusian surface on July 22, 1972. It had an internal refrigerator to protect the internal components from extreme the environment.
It sent data for 50 minutes. It confirmed that the Venusian atmosphere was relatively clean from the surface.
- Venera 9
Venera 9 consisted of an orbiter and a lander. The orbiter was the first spacecraft to orbit Venus and the lander was the first spacecraft to send an image from another planet.
Information from the lander was first sent to the orbiter and then to Earth.
- Venera 10
Sister of Venera 9 consisted of an orbiter and a lander. It also sent black and white images from the surface.
- Venera 11
Another lander which is considered partially successful because most of the instruments like colour cameras failed.
But it did detect the evidence of lightning and thunder.
- Venera 12
Again, a partially successful mission had a colour camera which failed to return any images.
- Pioneer Venus 1
Pioneer 1 was launched by NASA in May 1978. It carried out 17 experiments in total, one of which was a radar mapper which mapped the whole planet.
It’s mission ended in 1992.
- Pioneer Venus 2
Pioneer 2 consisted of four probes, one large and three small. Two of the three lander probes survived the impact and returned data for 67 minutes.
- Venera 13
Venera 13 was the first spacecraft to return colour images from the surface of the Venus.
It also had a driller to examine the soil sample to determine the planet’s composition.
The probe lasted for 127 minutes on the surface.
- Venera 14
Sent just five days after Venera 13, it also sent back colour images and determined the soil composition.
The probe functioned for 57 minutes.
- Venera 15
Venera 15 and 16 were orbiter missions designed to obtain images of the surface using radar system.
Both the spacecraft’s mapped approximately one- fourth the planet’s surface.
- Venera 16
Identical to Venera 15.
- Vega 1
The Vega mission had 3 major goals: to place landers on the surface of the Venus, to deploy balloons in the atmosphere and to observe the Comet Halley.
The lander measured the atmospheric pressure and lasted for 56 minutes.
The balloon travelled 11,600 km before losing communication.
In total both Vega 1 and Vega 2 took 1500 images of comet Halley. The images found that the comet had a rotation period of 53 hours.
- Vega 2
Identical to Vega 1
Magellan mapped over 98% of the planet’s surface using Synthetic Aperture Radar (SAR). It created the best radar mapping of planet Venus than any other probe.
It found few impact craters suggesting that the surface is geologically new.
- Venus Express
Venus Express was the first Venus exploration mission by the European Space Agency (ESA) launched in 2005.
It is the longest lasting Venus mission ever which lasted till 2014.
Japanese probe Akatsuki is the only probe currently studying planet Venus.
Launched in 2010, it failed to enter the orbit initially but re-entered in 2015.
Images from Akatsuki revealed something similar to a jet stream in the Venusian atmosphere ranging from 45 to 60 km in altitude.
Dense clouds and global warming has made this planet super hot.
Considering how global warming is affecting planet Earth, do you think Earth will turn into Venus one day?
Prajyot KumbharjuvekarCo-founder of Astronomiac
Prajyot is a writer and co-founder of Astronomiac. Writer at day and reader at night, he writes everything about astronomy.