Gravity, Space and the Solar System

These flashcards cover key concepts related to gravity, space, the solar system, and significant astronomical instruments.

Gravity

The force that keeps planets in orbit around the Sun and moons orbiting planets.

Axis

The imaginary line through Earth's center around which it spins, causing day and night.

Revolution

The movement of Earth traveling around the Sun, which causes the seasons; takes about 365 days.

Kuiper Belt

A region of icy objects beyond the orbit of Neptune.

Phases

The changing amounts of the lit side of the Moon that causes it to appear to change shape over time.

Seasons

The result of the changing positions of Earth and the Sun due to Earth's tilt and revolution.

Light-years

A unit of measurement for distances in space, representing the distance light travels in one year, nearly 6 trillion miles.

Hubble Space Telescope

The first major space telescope launched by NASA in 1990 that orbits Earth outside the atmosphere.

James Webb Space Telescope (JWST)

The most powerful and largest space telescope ever built, launched on December 25, 2021.

International Space Station (ISS)

A moving laboratory in space where astronauts can live and conduct research.

Asteroid Belt

The region between Mars and Jupiter that contains rocky objects.

Dwarf Planet

An object that orbits the Sun but is not large enough to be a full planet, e.g., Pluto.

Geocentric Model

The Earth-centered model of the universe, historically believed by scientists like Ptolemy and Aristotle.

Heliocentric Model

The Sun-centered model proposed by Copernicus, later supported by Galileo.

Rotation

The spinning of Earth on its axis, which causes day and night and takes 24 hours.

Tilt

The angle of Earth's axis, approximately 23.5°, which, combined with its revolution, causes seasons.

Inner Planets

Mercury, Venus, Earth, and Mars; made of rock and metal and smaller in size.

Outer Planets

Jupiter, Saturn, Uranus, and Neptune; mostly made of gas or ice.