UNIT 8-ASTRONOMY

Lisää tämän kaltaisia

Energy Conservation

luonut Nadiehsda Anderson

Adaptations of Aquatic Plants

luonut Alister Aroza

Energy System

luonut arif shafie

E.M. Spectrum

luonut Peter Clark

UNIT 8-ASTRONOMY

Red Shift - Observed shift in light wavelengths occurring when a light source is moving away from an observer.

Black Holes - A star in which matter is condensed and its gravity field is so strong that light cannot escape.

Irregular Galaxy - Galaxy that contains clouds of gas and dust and stars that are in the early stages of their life cycles.

Spectroscopes - An instrument that separates visible light into its various wavelengths.

Radio Telescopes - An instrument consisting of a reflector, a receiver, and an antenna used to collect radio waves from space.

Constellations - Group or pattern of stars.

Light-Year - A measure of the distance light travels in one year, which equals to 9.5 X 10 (to the 12th power) km.

Spiral Galaxy - A disk-shaped galaxy with arms that rotates round a dense center.

Refracting Telescope - An instrument that uses an objective lens to bend light toward the focal plane where the image is formed.

Expanding Universe - Theory that states the universe is currently expanding and shall continue to do so.

Nebula - A low density cloud of gas and dust in which a star is born.

Fusion - The process of two low mass nuclei being joined to form one nucleus; the source of a star's light and thermal energy.

Absolute Magnitude - A measure of a star's actual brightness.

Reflecting Telescope - An instrument in which light is collected, reflected, and focused by a concave mirror and the image formed is magnified in the eyepiece.

Big Bang - A theory stating that the universe originated from the explosion of a huge mass of matter, which cooled, collected into clouds, and formed galaxies.

Main Sequence Star - A star that lies along a diagonal from upper left to lower right on the Hertzsprung-Russell diagram; uses up its hydrogen fuel at a steady rate.

Elliptical Galaxy - A system of stars that contains little dust and gas and may be composed of millions to trillions of stars.