Moons notes

Satellite

Natural or artificial bodies that revolve around planets.

Lunar Rocks

Rocks brought back by the Apollo mission, estimated to be 4.6 billion years old, originating from the moon.

What has no atmosphere?

The surface of the moon has no atmosphere.

What are the four possible explanations for the moon's formation?

1. The moon was a separate body captured by Earth's gravity. 2. Formed at the same time from the same materials as Earth. 3. Newly formed Earth was spinning so fast that a piece flew off and became the moon. 4. A large Mars-sized object collided with Earth while it was still forming.

Phases of the Moon

New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, Waning Crescent.

Waxing

When the moon is waxing, the sunlit fraction visible from Earth is getting larger.

Waning

When the moon is waning, the sunlit fraction visible from Earth is getting smaller.

Solar Eclipse

Occurs when the moon comes between the Earth and the sun.

Lunar Eclipse

Occurs when the Earth comes between the sun and the moon, casting a shadow on the moon.

Annular Eclipse

Occurs when the edge of the sun remains visible as a bright ring around the moon.

Total Solar Eclipse

Occurs when the new moon comes between the sun and the Earth, casting the darkest part of the shadow.

Which two planets don't have moons?

Mercury and Venus.

Moons of Mars

Mars has two moons, Phobos and Deimos, which are dark, rocky, and asteroid-like.

Moons of Jupiter

Jupiter has 80 moons; the 4 largest are Europa, Ganymede, Callisto, and Io, known as Galilean Satellites.

Moons of Saturn

Saturn has 83 moons, with Titan being the largest.

Moons of Uranus

Uranus has 27 moons, several made of ice and rock; Miranda has the most unusual terrain.

Moons of Neptune

Neptune has 14 moons, including Triton, which is retrograde and geologically active with ice volcanoes and geysers.

Moons of Pluto

Pluto has 5 moons: Charon, Nix, Hydra, Styx, and Kerberos; Charon is so large that Pluto and Charon orbit each other like a double planet.

Comets

Small bodies of ice, rock, and cosmic dust loosely packed together, forming 'dirty snowballs'.

Comet Tails

Results from comets passing close to the sun, causing ice to melt and releasing gas/dust.

Ion Tails

A type of comet tail made of ions originating from the solid nucleus of the comet.

Asteroids

Small, rocky bodies that revolve around the sun.

Meteorite

A meteoroid that enters Earth's atmosphere and strikes the ground.

What is the difference between neap and spring tides?

Spring tides occur when the sun, moon, and Earth are aligned; neap tides happen when they are at a right angle.

Torino Scale

A system that rates the hazard level of an object moving towards Earth.

Meteor

A bright streak of light caused by a meteoroid or comet dust burning up in the atmosphere.

Meteor Shower

An event where several meteors pass by Earth.

Why are most craters on Earth no longer visible?

Because of weathering, erosion, and tectonic activity.