Being the closest planet to Earth, Venus has always been a desirable target for amateur astronomers for their first interplanetary exploration. That said, this planet was once the focal point of all space exploration in the late 1960s and 1970s.
Since the mid 20th century, many important and fascinating things have been uncovered regarding the planet, for example its toxic and unbearable atmosphere, cyclones near the south pole, and surprisingly low magnetic field and much more. While life is not possible on this planet, not now, not ever, it can still help us understand important planetary physics. Here are some of the fascinating facts about Venus.
Mass: 4.86×1024 kg
Density: 5.243 g/cm3
Surface Temperature: 462 °C
Surface Gravity: 8.87 m/s2
Diameter: 12,104 km
First Recorded Discoverers: Babylonian astronomers
20. The fact that Venus orbits the Sun (not the Earth) was first discovered by Galileo Galilei in the 17th century. Then in 1761, Russian genius Mikhail Lomonosov discovered the Venusian atmosphere, which was later studied by the German astronomer named Johann Schröter.
19. Venus’ atmosphere is mostly comprised of Carbon dioxide and nitrogen, though sulfur dioxide, argon, and water vapor are also found in trace amounts. Carbon dioxide accounts for 96.5% of the atmosphere, nitrogen 3.5%, and sulfur dioxide for about 0.015%. Carbonyl sulfide and other hydrogen compounds are found in trace amounts.
18. The planet’s magnetic field is much weaker than that of the Earth. When researchers first discovered this fact in 1960s, they were surprised as they were expecting some sort of magnetic field due to its resemblance to the Earth’s size. One possibility is that Venus doesn’t have a solid core which is responsible for the dynamo effect.
17. Though not much is known about the internal composition of Venus, its similar mass and size suggest that it has more or less the same structure i.e. a core, followed by a mantle and the crust. Its metallic core is approx. 6,000 km wide, the mantle is about 3,000 km thick and the crust may be about 10-20 km thick.
Size comparison of Venus and Earth
16. From earth, it is the second brightest object in the night sky. With an apparent magnitude of -4.6, only the moon outshone Venus in a clear night sky. Most of the times it is bright enough to be scantly visible to be seen by naked eye in the daytime.
15. On Venus, a day lasts longer than a year. Not sure how this is possible? A day on any planet is defined by its complete rotation around its axis, while a full revolution around the Sun defines a year on the planet. Venus takes about 224.7 Earth days to complete one orbit around the Sun, however, one revolution around its axis takes 243 Earth days (sidereal day).
14. In the next 4-5 billion years or so, the Sun will engulf planet Venus before reaching its apogee of red giant phase. Although researchers are still not sure the Sun will entirely cover the Earth or not, by the time it reaches near Venus, Sun’s flare would definitely destroy life on this planet.
13. Due to its similarity in mass and size, Venus is often called as Earth’s sister planet. The calculated diameter of the planet is about 12,103.6 km, which is just 634.4 km less than that of the Earth, while it has about 81% of the total Earth’s mass. However, the Venusian climate is extremely different than the Earth’s.
12. Researches over the years indicate that Venusian surface is much drier. During the early stages of its formation, extreme radiation from the Sun evaporated water from the planet’s surface quickly. The existence of liquid water on Venus is almost impossible due to its extremely hot atmosphere. Today, almost the entire planet is engulfed by active volcanoes.
Computer generated ‘Crater Farm’ on Venus
11. Venus’ extreme brightness has often lead to be misidentified as a UFO. At its best, the planet outshine Sirius, the brightest star from Earth’s point of view. Its successive appearances and a very unique position, relative to the Sun is what causes this mishap over and over again.
10. The planet has no proper natural satellite. However, it does have a temporary quasi-satellite and few trojan moons. The quasi-satellite, designated as 2002 VE68, was the first of such satellite to be discovered around a planet in the Solar System. From the Earth’s point of view the satellite appears to be revolving around Venus, but in reality it orbits around the Sun.
Diagram of quasi-satellite orbit
Venus also has two other trojans moons named 2001 CK32 and 2012 XE133, both of whom were once potentially hazardous asteroids to Earth. Sometime in the 17th century, Giovanni Cassini claimed that he detected a moon orbiting around the planet Venus, which he named Neith. Over the course of 2 centuries, Neith was reported by various observers, however, it was later identified as some sort of stellar activity on its immediate background.
9. First empirical studies were conducted on Venus after the initial success of the Venera mission in the 1960s. It was then followed by NASA’s Mariner 2, which became the first major interplanetary mission after gathering several important data from the planet.
8. Before the 1960s, many believed that Venus could possibly harbor life due to its similarity in shape and size to our planet. However, after the success of Russian and American missions to Venus in the later half of the 20th century, this speculation started to fade away after researchers began examining the Venusian atmosphere more closely.
With a scorching temperature of about 462 °C and atmospheric pressure up to 90% of that the Earth’s, Venus is surely not a place for life to take harbor.
7. According to ancient astronomical manuscripts, Venus was known to several historical civilizations mostly as the “evening star” and the “morning star.” Based on this, it can be assumed that they understood this planet as not one but two separate objects. One such civilization was the Greeks, who believed that it was two separate stars named Phosphorus and Hesperus.
6. After Soviet’s Venera missions and NASA’s Mariner 2, more than two dozen flybys and space probes have been successfully sent to Venus. One of the most important space probes sent to Venus was Magellan, which mapped almost the entire planet with Synthetic Aperture Radar technology and it also obtained important data such as topography, slope, radiometry, etc. over the period of 5 years.
Artist’s impression of Mariner 2
5. European Space Agency’s most recent space probe to Venus named the Venus Express, which was deorbited in 2015, revealed a fascinating evidence of lightning on the planet’s atmosphere. The observed lightning was extremely different from anything on the Earth or even other planets as it was not associated with water, instead was caused by clouds made composed of sulfuric acid.
4. A phenomenon known as supperrotation exist almost exclusively on the planet’s atmosphere. It first came into our knowledge in 1960s, when it was discovered that winds in the upper atmosphere of the planet blow almost 60 times faster than its surface.
A full rotation of the planet on its axis takes about 243 Earth days, but with a speed of 200 m/s, its atmosphere completes that in just four Earth days. Apart from Venus, supperrotation is also evident on Saturn’s moon Titan.
3. According to NASA, atmospheric pressure on Venus is around 80-100 times that of the Earth’s. To put this into context, the amount of pressure felt by a human body on the Venusian surface would be almost equal to what is experienced deep below the oceans on the Earth.
2. It is one of the two planets in our solar system that rotates in a retrograde motion i.e. rotating in the opposite direction of Sun’s own rotation around its axis. One possible explanation might be a hellacious collision between the planet and other body sometime during the planet’s history, which might have forced the planet to change its rotation. Apart from Venus, Uranus also rotates in a retrograde motion along its axis.
1. Venus is perhaps the hottest planet in our solar system. Well, some of you might be asking how this is possible? What about planet Mercury? We know that Mercury is the closest planet to Sun, and it receives solar radiation way more than any planet in our solar system. But due to its extremely small size, Mercury’s gravitation is so weak that it cannot hold a considerable amount of atmosphere around it.
View of Venus from Synthetic Aperture Radar from Magellan
The lack of atmosphere means that Mercury is unable to trap heat and radiation inside, just like the Earth. Venus, on the other hand, has a thick and rather a toxic atmosphere composed of carbon dioxide and nitrogen, which traps the maximum amount of heat inside in a one-way mechanism. The average surface temperature is 462 °C. No wonder why scientists call this a hellish planet.