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The Universe Y10-SS
Chapter 7 Pearson Places
Term | Definition |
---|---|
Accretion | The process in which particles of dust and rock slowly come together due to gravity to form a larger object. |
Binary star system | Two stars that orbit a common centre of mass. |
Black hole | Also known as a singularity, a collapsed star so massive that not even light can escape from its gravitational field. |
Galaxy | A large group of stars attracted to one another by gravity. |
Gravitational lensing | The bending of light rays due to the distortion of space caused by a massive object such as a black hole. |
Gravity | The force that causes all matter to collect together. |
Light-year (l.y.) | The distance light travels in a year. Approximately 9 500 000 000 000 |
Milky Way | The galaxy in which the solar system is located. |
Nebula | A cloud of gas found in the empty space between stars; the birthplace of new stars. |
Nuclear fusion | The process in which hydrogen is converted into helium to produce light and heat. |
Parallax | A technique used to measure the distance to other stars. |
Parsec | An astronomical unit of length equal to 3.26 l.y. |
Protoplanetary disk | Disk of gas surrounding a protostar that will form into planets. |
Protostar | A collapsing cloud of gas that will become a star. |
Radiation pressure | The force produced by radiation from pressure caused by heat |
Stellar parallax | The apparent change in position of a star throughout the year due to the Earth's motion around the Sun. |
Supermassive black hole | A black hole millions or billions of times the mass of our sun found at the centre of a galaxy. |