Lecture Notes on Planets

Flashcards covering the key terms and definitions related to planets, including inner planets, outer planets, and individual planets.

Inner Planets

Mercury, Venus, Earth, and Mars; characterized by rocky crusts, dense mantles, and very dense cores.

Outer Planets

Jupiter, Saturn, Uranus, and Neptune; also known as Jovian planets or gas giants, composed mostly of hydrogen and helium, and they all have rings.

Asteroid Belt

The region separating the inner and outer planets, located between Mars and Jupiter.

Period (of a planet)

The time it takes a planet to revolve around the sun (its year).

Astronomical Unit (AU)

The average distance from Earth to the sun, approximately 93,000,000 miles.

Terrestrial Planets

Earth-like planets with rocky crusts, dense mantles, and very dense cores (Inner Planets).

Mercury

The smallest planet, closest to the sun at 0.4 AU, with a period of 88 days and extreme temperature variations; it has almost no atmosphere and is covered with impact craters.

Venus

0.7 AU from the sun, with a period of 225 days and a temperature of 475 degrees Celsius; similar to Earth in diameter, mass, and gravity but with a runaway greenhouse effect and a very thick atmosphere.

Earth

One AU from the sun; the largest terrestrial planet.

Mars

1.5 AU from the sun, with a period of 687 days and a temperature range of 27 to -333 degrees Celsius; about half the size of Earth with a thin atmosphere and frozen polar ice caps.

Olympus Mons

The largest known volcano in the solar system, located on Mars.

Valles Marineris

A vast canyon system on Mars, as long as the USA is wide.

Jovian Planets

Also known as gas giants, composed mostly of hydrogen and helium; Jupiter, Saturn, Uranus, and Neptune.

Jupiter

5.2 AU from the sun, with a period of 12 Earth years; the fastest rotating and largest planet, with a strong magnetic field and a great red spot (a giant storm).

Saturn

9.5 AU from the sun, with a period of 30 Earth years; characterized by colored bands of gas and the most elaborate ring system; it has the lowest density of any planet.

Uranus

19.2 AU from the sun, with a period of 84 Earth years; the slowest rotating Jovian planet, rotating on its side with an extreme axis tilt.

Neptune

30 AU from the sun, with a period of 165 Earth years; the most distant, coldest, and smallest Jovian planet, with great dark spots and the fastest winds in the solar system.