Venus Flashcards
Venus: Basic Facts
Venus is the second planet from the Sun, often called Earth’s ‘twin’ due to its similar size and composition.
Venus: Size and Structure
Diameter: 12,104 km (95% of Earth’s); Mass: 0.82 times Earth’s; Surface gravity: 0.91 times Earth’s.
Venus: Atmosphere Composition
Thick atmosphere mostly composed of CO₂ (96.5%) and nitrogen (3.5%) with traces of sulfur dioxide, creating a runaway greenhouse effect.
Venus: Surface Temperature
The hottest planet in the solar system, with average surface temperatures around 467°C (872°F), hot enough to melt lead.
Venus: Greenhouse Effect
Extreme heat is due to a runaway greenhouse effect caused by thick CO₂ clouds trapping heat and preventing it from escaping.
Venus: Surface Features
Covered with vast plains, highland regions, and volcanoes; lacks plate tectonics but shows signs of past volcanic activity.
Venus: Volcanic Activity
Features massive shield volcanoes like Maxwell Montes and possibly active volcanoes today, based on recent data from orbiters.
Venus: Rotation
Rotates very slowly and in the opposite direction (retrograde rotation) compared to most planets; one Venusian day is longer than its year.
Venus: Length of Day and Year
One Venusian day = 243 Earth days; One Venusian year = 225 Earth days, making a day longer than a year!
Venus: Magnetic Field
Lacks a strong intrinsic magnetic field due to its slow rotation and lack of a convection-driven dynamo in its core.
Venus: Winds and Weather
Super-fast winds in the upper atmosphere (~360 km/h) create a thick, constant cloud cover, but surface winds are slow.
Venus: Cloud Composition
Clouds are made of sulfuric acid droplets, making Venus highly reflective and extremely hostile to spacecraft.
Venus: Air Pressure
Surface pressure is about 92 times Earth’s (like being 900m underwater), making landers highly susceptible to crushing.
Venus: Exploration
Studied by various missions, including Soviet Venera landers, NASA’s Magellan (radar mapping), and upcoming ESA/NASA missions.
Venus: Venera Missions
The Soviet Venera probes (1960s-1980s) were the only landers to survive Venus’ harsh conditions briefly, sending back surface images.
Venus: Magellan Mission
NASA’s Magellan orbiter (1990-1994) mapped 98% of Venus’ surface using radar, revealing volcanic plains and impact craters.
Venus: Akatsuki Mission
Japan’s Akatsuki spacecraft (since 2015) studies Venus’ atmosphere, cloud patterns, and weather dynamics.
Venus: Future Missions
Upcoming missions include NASA’s DAVINCI+ (studying the atmosphere) and VERITAS (mapping the surface).
Venus vs. Earth
Similar in size and composition, but Venus has extreme greenhouse conditions, lacks liquid water, and rotates in the opposite direction.
Venus’ Visibility
Brightest natural object in Earth’s night sky after the Moon, often called the ‘Morning Star’ or ‘Evening Star.’
