Earthlike Planets: Venus and Mars

These flashcards cover essential vocabulary related to Venus and Mars as outlined in the lecture notes.

Venus

A planet that is similar in size, mass, and density to Earth, known for its thick carbon dioxide atmosphere.

Retrograde rotation

A backwards rotation of a planet with respect to its revolution; Venus rotates backwards relative to its orbit around the Sun.

Greenhouse effect

A phenomenon causing trapped infrared radiation by CO2 in the atmosphere, leading to extreme surface temperatures on Venus.

Atmosphere of Venus

Primarily composed of 96% CO2, with very little oxygen and water vapor.

Venera missions

Russian missions that sent probes to Venus to study its surface in the 1970s and 1980s.

Magellan

NASA spacecraft that mapped the surface of Venus using RADAR.

Mars

The fourth planet from the Sun, known for its thin atmosphere, seasonal weather changes, and polar ice caps.

Opposition (in astronomy)

When Mars is opposite the Sun in the sky, making it closest to Earth.

Seasons on Mars

Experienced due to the axial tilt; seasonal changes influenced by the thin CO2 atmosphere.

Viking missions

NASA missions in the 1970s that landed on Mars to study its surface and weather.

Phobos and Deimos

The two small moons of Mars, believed to be captured asteroids.

Roche limit

The distance from a planet within which a moon cannot remain intact due to tidal forces.

Aurora

Natural light display in the sky, often seen in high-latitude regions, produced by the interaction of solar wind and a planet's magnetic field.

Cassini mission

A NASA mission that focused on Saturn and its moons, providing insights into their geology and atmospheres.

Titan

Saturn's largest moon, notable for its thick atmosphere and surface lakes of methane.

Albedo

A measure of how much light reflects off a surface; Venus has a high albedo due to its reflective cloud cover.

Mean surface temperature of Venus

Approximately 480°C due to the greenhouse effect.

Pioneer mission

NASA spacecraft that studied Venus and contributed to our understanding of its environment.