Unit 9: Space

Mass

amount of matter in an object  

Microgravity

zone of weak gravity (e.g., orbiting in a spacecraft)

Weight

Force exerted on an object by gravity

Accommodations

the process of adapting or adjusting to someone or something.

Atmosphere

the envelope of gases surrounding the earth or another planet.

Gravity

force of attraction between two objects due to their masses

Manned space exploration

spaceflight with a crew or passengers aboard a spacecraft, often with the spacecraft being operated directly by the onboard human crew. Spacecraft can also be remotely operated from ground stations on Earth, or autonomously, without any direct human involvement.

Solar system

the collection of eight planets and their moons in orbit around the sun, together with smaller bodies in the form of asteroids, meteoroids, and comets. The planets of the solar system are (in order of distance from the sun) Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Solar radiation

electromagnetic radiation emitted by the sun.

Asteroid

a small, rocky body that orbits the Sun; a large asteroid belt lies between Mars and Jupiter

Comet

an object that orbits the Sun; made of frozen water and dust, and has a tail of gas and dust particles that points away from the Sun

Meteor

a small piece of matter from outer space that becomes a streak of light when it falls through the Earth’s atmosphere and burns up; also known as a falling or shooting star

Orbit

the path that one object in space follows as it revolves around another object in space

Revolve

one complete orbit made by a planet or satellite around another object

Rotate

the spinning of an object on its axis

Surface gravity

the force of gravity at the surface of the Earth or other celestial body

Astronomical Unit (AU)

a unit of measurement equal to 149.6 million kilometers, the mean distance from the center of the earth to the center of the sun.

Inner planet

a planet whose orbit lies within the asteroid belt, i.e. Mercury, Venus, Earth, or Mars.

Outer Planet

a planet whose orbit lies outside the asteroid belt, i.e. Jupiter, Saturn, Uranus, or Neptune.

Space probe

an unmanned exploratory spacecraft designed to transmit information about its environment.

Space Shuttle

a rocket-launched spacecraft, able to land like an unpowered aircraft, used to make repeated journeys between the earth and earth orbit.

Satellite

a rocket-launched spacecraft, able to land like an unpowered aircraft, used to make repeated journeys between the earth and earth orbit. OR a celestial body orbiting the earth or another planet.

International Space Station (ISS)

he International Space Station is a large space station assembled and maintained in low Earth orbit by a collaboration of five space agencies: NASA, Roscosmos, JAXA, ESA, CSA, and their contractors. ISS is the largest space station ever built.

Terrestrial Planets

A terrestrial planet, telluric planet, or rocky planet, is a planet that is composed primarily of silicate, rocks or metals. Within the Solar System, the terrestrial planets accepted by the IAU are the inner planets closest to the Sun: Mercury, Venus, Earth and Mars.

Gas Giants

a large planet of relatively low density consisting predominantly of hydrogen and helium, such as Jupiter, Saturn, Uranus, or Neptune.