Central Star - The Sun and Inner Planets

Study Notes

Central Star - The Sun

The Sun is the brightest star in the Solar System and has existed for about 4.6 billion years, with an estimated 5 billion years remaining.
Emits various types of electromagnetic radiation, including ultraviolet waves, radio waves, gamma rays, X-rays, microwaves, and infrared rays.

Inner Planets

Mercury

Named after the Greek messenger god Hermes.
Orbital period: 88 Earth days; rotational period: 58 Earth days.
Surface temperature ranges from 427°C (day) to -173°C (night).
Known as the morning and evening star; it has no moons or atmosphere due to proximity to the Sun.

Venus

Named after the Greek goddess of beauty, Aphrodite.
Orbital period: 255 Earth days; rotational period: 243 Earth days (retrograde rotation).
Surface temperature reaches about 482°C.
Earth’s twin in mass and size, with a thick atmosphere rich in carbon dioxide and active volcanoes under cloud cover.

Earth

Named after the primordial deity Gaia.
Orbital period: 365 days; rotational period: 24 hours.
Average surface temperature: 15°C.
Known as the "Blue Planet" due to its water-covered surface and is the only known planet to support life, benefiting from a multilayered atmosphere with oxygen.

Mars

Named after the Greek god of war, Ares.
Orbital period: 687 days; rotational period: 24.6 hours.
Known as the "Red Planet" due to oxidized iron on its surface.
Features Olympus Mons (the largest volcano) and Valles Marineris (the largest canyon).
Has two moons: Deimos (farther away, predicted to escape Mars's gravity) and Phobos (predicted to crash into Mars).

Asteroid Belt

The boundary between the inner and outer planets, consisting of a collection of planetary debris.
Theories suggest it may consist of remnants from a destroyed planet or leftover materials from the Solar System's formation.
Asteroids become meteors upon atmospheric entry and meteorites upon disintegration.

Outer or Jovian Planets

Jupiter

The largest planet, named after the Greek god Zeus.
Its atmosphere is primarily hydrogen, containing a persistent storm system called the Great Red Spot, which measures 25,000 km in diameter.
Hosts 62 moons; notable ones include Ganymede (largest, comparable to a planet), Callisto (atmosphere of carbon dioxide and molecular oxygen), Io (geologically active), and Europa (features a frozen ocean).

Saturn

The second-largest planet, named after the titan Cronus (Kronos).
Famous for its extensive rings composed of ice and rock, divided into three groups, including the Cassini Division.
Its atmosphere includes hydrogen, helium, ammonia, methane, and water, with wind speeds reaching approximately 1770 km/h.
Hosts 24 moons; Titan is the largest, known for its dense atmosphere.

Description

Explore the fascinating world of our Solar System's brightest star, the Sun, and learn about the inner planets: Mercury, Venus, Earth, and Mars. This quiz covers the Sun's energy emission and fundamental facts about each inner planet's characteristics. Test your knowledge on solar and planetary science!