Copy of Physics- Space Unit Test

Frames of Reference

A set of axes used to describe the positions or motions of things, such as the equator and prime meridian used to describe locations on Earth.

Constellations

Unchanging patterns made by stars in the sky that resemble objects.

Polaris/North Star

A star near which the other stars appear to revolve, used for finding direction at night.

Azimuth

An angle measured clockwise from the north, used to measure the direction of a celestial body.

Altitude

The angle above the horizon in degrees, used to measure the height of a celestial body.

Astrolabe

A device used to measure the altitude of an object, invented by the Greeks.

Compass

A tool used to measure the azimuth of an object, improving navigation.

Geocentric Model

A debunked theory that the Earth is the center of the universe, with the sun and planets revolving around it.

Heliocentric Model

A model proposed by Nicholas Copernicus, placing the Sun in the center with a rotating Earth revolving around it.

Solstice

The longest or shortest period of daylight in the year.

Equinox

Days of equal length, marking the transition between seasons.

Universal Gravitation

The law explaining the elliptical orbits of planets, stating that there is a gravitational force between all objects.

Spectroscope

A device that produces a focused spectrum by passing light through a narrow slit and prism.

Spectroscopy

The science of color, using spectral lines to identify elements.

Diffraction Gratings

Devices made of closely spaced slits used to split light into spectra.

Absorption

The dark gaps observed in a continuous spectrum when white light passes through a cooler substance.

Spectral Analysis

The method used by astronomers to learn about distant stars by analyzing their spectra.

Doppler Effect

The change in pitch of a sound or light wave due to the motion of the source relative to the observer.

Optical Telescopes

Telescopes that gather information based on visible light.

Radio Telescopes

Telescopes that detect electromagnetic energy in the form of radio waves, providing advantages over optical telescopes.

Wavelengths and Frequency

The inverse relationship between wavelength and frequency.

Radio Interferometry

The arrangement of multiple small radio telescopes to achieve greater resolving power.

Triangulation

A technique used to measure the distance to a star by creating a baseline and measuring angles.

Parallax

The apparent change in position of stars due to the Earth's orbit, used to determine distances to nearby stars.

Light-year

A unit of distance used to measure vast distances in the universe, equal to the distance light travels in one year.

AU

Astronomical Unit, the average distance from Earth to the Sun, approximately 150 million kilometers.