Planet Profile: Venus
1. Basic Facts
Venus, the second planet from the Sun, is often called Earth’s twin due to its similar size, mass, and composition. However, beyond these similarities, Venus is an incredibly hostile world with scorching temperatures, crushing atmospheric pressure, and toxic clouds. It has a diameter of 12,104 km (7,521 miles), making it slightly smaller than Earth. Unlike Earth, Venus has a thick, dense atmosphere composed mostly of carbon dioxide, trapping heat and creating the hottest planetary surface in the Solar System. Venus has no moons or rings, and its surface is dominated by vast volcanic plains, mountains, and deep craters. Despite its extreme conditions, Venus has fascinated astronomers for centuries and remains an important target for future exploration.
2. Orbital & Rotational Characteristics
- A Year Shorter than a Day – Venus completes an orbit around the Sun in 225 Earth days, but it rotates on its axis extremely slowly, taking 243 Earth days to complete one full spin.
- Retrograde Rotation – Unlike most planets, Venus spins backward (retrograde motion), meaning the Sun rises in the west and sets in the east.
- Closest Planet to Earth – Venus comes closer to Earth than any other planet, making it one of the brightest objects in our night sky.
3. Extreme Climate & Atmosphere
- Hottest Planet in the Solar System – Venus experiences an extreme greenhouse effect, leading to surface temperatures of 900°F (475°C)—hot enough to melt lead.
- Thick Atmosphere – The carbon dioxide-rich atmosphere is 92 times denser than Earth’s, exerting pressure equivalent to being 3,000 feet underwater.
- Acidic Clouds – Venus has clouds made of sulfuric acid, creating a thick, reflective layer that makes the planet highly visible from Earth.
- Runaway Greenhouse Effect – Scientists believe Venus once had oceans, but due to extreme heating, all water evaporated, leading to its current hellish climate.
4. Surface & Geological Features
- Volcanic Landscape – Venus is covered in vast lava plains, massive volcanoes, and large impact craters.
- Mountains & Highlands – The tallest mountain, Maxwell Montes, is about 11 km (7 miles) high, taller than Mount Everest.
- Mysterious ‘Tesserae’ Terrain – Some regions show heavily deformed, layered terrain that suggests past tectonic activity.
- Few Impact Craters – Venus’s thick atmosphere burns up most meteors before they reach the surface, leaving relatively few craters.
5. Exploration & Discoveries
- First Planet Visited by a Spacecraft – Venus was the first planet explored by space probes, starting with NASA’s Mariner 2 in 1962.
- Soviet Venera Missions – The Venera landers (1970s-1980s) were the first (and only) spacecraft to successfully land on Venus and send images before being destroyed by the heat and pressure.
- Modern Missions – Future missions, including NASA’s VERITAS and ESA’s EnVision, aim to study Venus’s geology, atmosphere, and potential past habitability.
6. The Mystery of Venus’s Past & Future Exploration
Venus may have once been habitable, with liquid water and a more Earth-like climate billions of years ago. However, due to runaway greenhouse effects, it became an uninhabitable inferno. Scientists continue to explore whether Venus once supported life and how studying it can help us understand climate change on Earth. Despite its extreme environment, future missions aim to explore Venus’s atmosphere and surface, with ideas ranging from floating cities to robotic landers capable of withstanding the planet’s harsh conditions.