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Unit 2 Part 2
Astronomy
Term | Deffinition |
---|---|
Chromosphere | - the first layor of the solar atmosphere found directly above the photosphere |
Corona | - the outer weak layer of the solar atmosphere |
Solar Wind | - steams of protons and electrons ejected at high speed from the solar system |
Sunspots | - a dark spot on the sun, which is cool by contrast to the surronding photosphere |
Prominence | - a concentration of gases above the solar surface tha tappears as a bright archlike structures |
Solar Flare | - a sudden and tremendous eruption in the solar chromosphere |
Aurora | - a bright display of ever-changing light caused by solar radiation interacting with the upper atmosphere in the region of the poles |
Nuclear fusion | - the way in which the sun produces energy |
Constellation | - an apparent group of stars originally named for mythical characters |
Binary Star | - one of two stars revolving around a common center of mass under their mutual gravitaional attraction |
Light years | - the distance light travels in a year |
Apparent magnitude | - the brightness of a star when viewed from the Earth |
Absolute magnitude | - the apparent brightness of a star if it were viewed from a distance of 32.6 light-years |
Main sequence star | - a star that falls into the main sequence catergorary on the H-R diagram |
Red Giant | - a large cool star of high luminosity |
Supergiant | - a very large very bright red star |
Cepheid Variable | - a star whose brightness varies periodically because it expands and contracts |
Nova | - a star that explosivly increases in brightness |
Nebulae | - a cloud of gas and/or dust in space |
Hertzsprung-Russell Diagram | - HR diagram |
Protostar | - a collapsing cloud of gas and dust destinded to become a star |
Supernova | - an exploding star that increases in brightness in brightness many times thousands of times |
Whaite dwarf | - a star that has exhausted most or all of its nuclear fuel and has collapased to a very small size |
Neutrin star | - a star of extremly high density composed entirely of neutrons |
Pulsar | - a variable radio source of small size that emits radio pulse in very regular periods |
Black Hole | - a massive star that has collapsed to such a small volume that its grvity prevents the escape of everything including light |
Galaxy | - a group of stars, dust, and gases held together by gravity |
Hubbles law | - a law that states that the galaxies are retreating from the Milky Way at a speed that is proportional to their distance |
Bug BAng Theroy | -the theory that proposes that the unicerse originated as a single mass |
Photosphere | -the region of the sun that radiates energy to space |