Venus: Quick Facts
Planetary Properties of Venus
Orbital Semimajor Axis: 0.72 Astronomical Units (108.2 Million Kilometers)
Orbital Eccentricity: 0.007
Perihelion: Approximately 0.72 Astronomical Units (107.5 Million Kilometers)
Aphelion: 0.73 Astronomical Units (108.9 Million Kilometers)
Mean/Average Orbital Speed: 35 Kilometers Per Second
Sidereal Orbital Period: 224.7 Days (0.615 Tropical Years)
Synodic Orbital Period: 583.9 Days (Solar)
Orbital Inclination to the Ecliptic: 3.39 Degrees
Greatest Angular Diameter (As Viewed From Earth): 64”
Overall Mass: 4.87 x 1024 Kilograms (0.82 of Earth’s Overall Mass)
Equatorial Radius: 6,052 Kilometers (0.95 of Earth’s Equatorial Radius)
Mean/Average Density: 5,240 Kilograms Per Meters Cubed (0.95 of Earth’s Mean Density)
Surface Gravity: 8.87 Meters Per Second Squared (0.91 of Earth’s Surface Gravity)
Escape Speed/Velocity: 10.4 Kilometers Per Second
Sidereal Rotation Period: -243 Days (Solar) [Retrograde Rotation]
Axial Tilt: 177.4 Degrees
Surface Magnetic Field: <0.001 of Earth’s Surface Magnetic Field
Magnetic Axis Tilt (Relative to Rotation Axis): N/A
Overall Mean/Average Surface Temperature: 730 Kelvins (854.33 Degrees Fahrenheit)
Number of Moons/Satellites: 0
Fact #1: The planet Venus is the second planet from the Sun and is one of the brightest objects in the sky (following the Sun and the Moon, respectively). Scientists often refer to the planet as Earth’s “sister planet” due to the fact that both are similar in mass (and size). Venus is also the closet planet to Earth, and can been seen during the twilight hours of sunrise and sunset. For this reason, Venus is often referred to as the “morning” or “evening” star.
Fact #2: Venus has an exceptionally slow rotation rate. In fact, it takes nearly 243 days (Earth days) for the planet to complete one rotation. However, one year on Venus (the time it takes to orbit the Sun) is significantly shorter than Earth, at only 225 days.
Fact #3: Unlike most planets that spin counterclockwise as they orbit the Sun, the planet Venus spins clockwise (similar to Uranus). This unique feature is known as retrograde rotation. Scientists remain unsure as to what caused Venus to spin in this manner. However, many astronomers have speculated that its retrograde rotation may have been caused by the impact of a large asteroid or comet in years prior. This would explain not only its retrograde rotation, but also the slow pace of its rotation.
Fact #4: Venus is the hottest planet in the solar system, and maintains an average temperature of nearly 863 degrees Fahrenheit. This extreme heat is a result of the planet’s proximity to the Sun, as well as its dense atmosphere which is nearly 96.5 percent carbon dioxide. This, in effect, helps to trap heat, causing a “greenhouse effect” across the planet. The planet’s temperature remains relatively stable due to the slow movement of solar wind across its surface.
Fact #5: Scientists believe that Venus maintains an atmospheric pressure that is 92 times the strength of Earth. The pressure is comparable to the bottom of Earth’s oceans.
Fun Facts about Venus
Fun Fact #1: Unlike other planets, Venus possesses no natural satellites (i.e. moons).
Fun Fact #2: Scientists believe that Venus once possessed vast oceans of water across its surface. However, as the planet’s temperature increased, these oceans rapidly evaporated.
Fun Fact #3: The Soviet Union launched the first space probe to visit Venus. The craft was launched in 1961, and was known as the Venera 1. The United States also sent two space probes to Venus in the early sixties (Mariner 1 and Mariner 2). However, the Soviet Union became the first country to successfully land a craft on the planet’s surface (Known as Venera 3). Venera 3 successfully landed on the surface in 1966, and managed to send only a handful of images back to scientists in the Soviet Union before the probe disintegrated in Venus’ harsh environment.
Fun Fact #4: In 2006, the European Space Agency launched the “Venus Express” spacecraft to investigate the planet Venus further. After numerous orbits of the planet, “Venus Express” observed more than one thousand volcanoes across the planet. The mission offered scientists an amazing perspective of the planet, as Venus maintains a dense atmosphere of sulphuric acid, which has made it difficult to study and observe from afar.
Fun Fact #5: It is believed by scholars that Venus was first discovered by the ancient Babylonians around 1600 BC. However, the famous mathematician, Pythagoras, is the first to discover that both the “evening” and “morning” star were the same object (Venus).
Fun Fact #6: Venus earned its name from the Romans, due to the fact that it was the brightest planet in Earth’s sky (after the Moon and Sun). “Venus” was the Roman goddess of love and beauty; terms that appear highly relevant due to the planet’s natural beauty from afar. As a result, the planet has often been associated with notions of love and romance across history.
Fun Fact #7: It is believed that Venus’ atmosphere can be divided into two categories: Upper and Lower. In the upper atmosphere (approximately 50 to 80 kilometers above the planet’s surface), Venus’ atmosphere is composed primarily of Sulphur dioxide and sulphuric acid. The density of the planet’s atmosphere is so intense that nearly sixty percent of the Sun’s sunlight is reflected by Venus’ clouds back into space.
Fun Fact #8: Scientists have been able to develop a detailed mapping of Venus and its surface with the help of radar imaging. Radar mapping has indicated startling finds for scientists and astronomers. On the surface of Venus lies massive plains that have been formed by ancient lava flows. Spacecraft (such as the 1990 Magellan) have also indicated the presence of more than 1,000 craters across the planetary surface.
“There are other planets besides the Earth and Mars. I’d like to remind you that studying Venus is vital to understanding life elsewhere.”— David Grinspoon
Quotes about Venus
Quote #1: “There is good evidence that Venus once had liquid water and a much thinner atmosphere, similar to Earth billions of years ago. But today the surface of Venus is dry as a bone, hot enough to melt lead, there are clouds of sulphuric acid that reach a hundred miles high and the air is so thick it’s like being 900 meters deep in the ocean.” -- Bill Nye
Quote #2: “Earth might one day soon resemble the planet Venus.” -- Stephen Hawking
Quote #3: “It’s one of the big mysteries about Venus: How did it get so different from Earth when it seems likely to have started so similarly? The question becomes richer when you consider astrobiology, the possibility that Venus and Earth were very similar during the time of the origin of life on Earth.” -- Davin Grinspoon
Quote #4: “There are other planets besides the Earth and Mars. I’d like to remind you that studying Venus is vital to understanding life elsewhere.” -- David Grinspoon
Quote #5: “The universe is hilarious! Like, Venus is 900 degrees. I could tell you it melts lead. But that’s not as fun as saying, ‘You can cook a pizza on the windowsill in nine seconds.’ And next time my fans eat pizza, they’re thinking of Venus!” -- Neil deGrasse Tyson
Quote #6: “Mars is much closer to the characteristics of Earth. It has a fall, winter, summer and spring. North Pole, South Pole, mountains and lots of ice. No one is going to live on Venus; no one is going to live on Jupiter.” -- Buzz Aldrin
Interior of Venus
Similar to Earth’s interior, Venus is composed of three layers that include a crust, mantle, and core. Scientists believe that the crust of Venus is approximately fifty kilometers thick, whereas its mantle is likely to be 3,000 kilometers thick, and core around 6,000 kilometers in diameter.
Scientists are unsure, however, about whether the planet’s core is liquid or solid. Recent evidence tends to suggest that Venus may possess a solid core, due to its lack of a strong magnetic field. Scientists argue that if Venus had a liquid core, the transfer of heat from its interior to the surface would allow for a strong magnetic field to develop. This does not appear to be the case, however.
Were you surprised by any of these facts about Venus?
In closing, the planet Venus continues to be one of the most fascinating objects in our solar system. With a volatile and hostile environment, intoxicating atmosphere, and tremendously high temperatures, it is unlikely that Venus will ever serve as a colony for Earth in the distant future. Nevertheless, the planet's natural beauty will continue to be admired by scientists and observers, alike, in the foreseeable future.
As more and more spacecraft and probes are launched by various countries, it will be interesting to see what new information can be gleaned about this fascinating planet and its place in the solar system and galaxy at large.
Suggestions for Further Reading:
Grinspoon, David Harry. A New Look Below the Clouds of our Mysterious Twin Planet. New York, New York: Perseus Publishing, 1997.
Marov, Mikhail Ya and David H. Grinspoon. The Planet Venus (The Planetary Exploration Series). New Haven, Connecticut: Yale University Press, 1998.
Taylor, Fredrick. The Scientific Exploration of Venus. New York, New York: Cambridge University Press, 2014.
Wikipedia contributors, "Venus," Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/w/index.php?title=Venus&oldid=876405656 (accessed January 7, 2019).
Questions & Answers
© 2019 Larry Slawson