A | B |
Constellation (def.) | a group of stars that appear to form a pattern in the sky. |
Best known constellation | Big Dipper |
Circumpolar constellations | Ursa Major Ursa Minor Cassiopeia |
Number or stars seen as circumpolar depends on | observers latitude |
Circumpolarisation is caused by | earth rotating its axis |
Earth turns | west to east |
What direction does the sky appear to turn | east to west |
Big Dipper is where in the sky in the fall | northern horizon |
Big Dipper is where in the sky in the spring | high over head |
The changes in position of constellations is caused by | the changing positions of earth's orbit around the sun |
Stars that make up the Summer Triangle | Vega-in Lyra the Harp, Altair-in Aquila the Eagle, and Deneb- top of Northern Cross, part of Cygnus the swan |
Most famous winter constellation | Orion the Hunter |
3 stars in the belt of Orion can find what 2 constellations | Canis major and Taurus the Bull and the Pleiades Star Cluster |
Closest star to earth | sun |
Average distance | 150 million km |
150 million Km equals how many au | 1 Au |
Light Year (def) | distance light travels in a year |
The bright red super giant star found forming Orion's right shoulder | Betelgeuse |
7th brightest star in the night sky | Rigel |
How many minutes does it take for light to reach Earth | 8 minutes |
Put star colors in order from hottest to coldest. | Blue, Yellow, Red |
Luminosity(def) | how bright a star is, depends on size and temperature |
The brightest star in our sky | Sun |
Red Giant (def and example) | large red star at least 10x diameter of the sun. Ex: Aldebaron |
Super Giant (def ) | largest of all stars; 100x more luminous |
Dwarf Stars (3 traits) | less luminous, very dense, remains of a red giant that ran out of fuel; color are red/orange/yellow |
Neutron stars (def) | distant heavenly object that emits rapid pulses of light and radio waves |
Why do twinkling stars occur? | They're due to Earth's atmosphere |
Nebulae(def) | space gas seen as faint glowing clouds |
Example of a nebulea | Sword of Orion |
Diffuse Nebulea(def) | gases glow from stars within them |
Dark Nebulea(def) | nebula not near a bright star |
Why do nebulae still hinder star gazing? | They absorb light which passes through them |
Protostar(def) | shrinking gas balls, caused by a swirl of gas forming dense areas. The gravity of the dense swirl in turn attracts near by gases so a ball forms |
A new star is born in our galaxy every | 18 days |
Stable State Star(def) | star that releases energy in enough force to counter balance gravity, star stops contracting |
Life Cycle of an average star | nebula, protostar, new star/stable state star, red giant, planetary nebula, white dwarf, black dwarf |
Life Cycle of a Massive Star | nebula, protostar, new star/stable state star, super giant, super nova, neutron star/pulsar,or black hole |
Super Nova(def) | explosion from a massive Super Giant; outer layer blasts away at end of Life Cycle; emits light, heat, X-rays, & neutrinos |
Black Hole (def) | denser than a neutron stars; light can NOT escape; located by X-rays detection |
Example of a black hole | Cygnus X1 in Cygnus the Swan |
galaxies (def) | systems containing millions or billions of stars, gas, & dust held together by gravity |
Example of a galaxy | milky way |
Spiral (def) | pinwheel shaped; our sun is on a spiral arm of the Milky Way; most common |
Quasar (def) | quasi stellar radio source, very far away, but the most luminous objects in the universe, thought to be galaxies with huge black holes in the center |
Diagram that compares star brightness (absolute magnitude) to a star temperature | Hertzsprung-Russel Diagram |
color with the shortest wavelength | violet |
color that is most difficult to deflect | red |
color with the lowest frequency | red |
Why is the ocean blue? | blue scatters more light; water absorbs other wavelengths;other colors are not scattered as much |
What color would the sky be without an atmosphere? | black |
What 2 forces need to be balanced to keep a satellite in orbit? | gravity and velocity |
What types of radiant energy are produced by stars? | visible light, radio waves, x-rays, ultraviolet, and infrared |
What does a spectroscope reveal about a star? | the chemical make up of a star |
ROY G BIV | red orange yellow green blue indigo violet |
twice the amplitude | wave height |
# of crests passing by a spot in a set amount of time | frequency |
launched in 1990 by the Shuttle Discovery | Hubble Space telescope |
speed of all electromagnetic waves | 300,000 km/sec |
Sources of dark-line spectra | Stars & the atmosphere of planets |
Sources of Continuous Spectra | Visible light from the sun, regular Tungsten light bulbs |
Sources of Bright-line Spectra | Neon signs, LED |
3 types of spectra | Bright-line, Dark-line, Continuous |
Synonym for Bright-line Spectra | Emission Spectra |
Synonym for Dark-line Spectra | Absorption Spectra |
Crest (Def) | Highest part of a wave |
Trough (Def) | Lowest part of a wave |
Wavelength (Def) | Distance from one crest to the next or one trough to the next |
Amplitude is a measure of the amount of ________ a wave has. | Energy |
Types of Electromagnetic Energy in order from the largest wavelength to the shortest | Radio waves, Microwaves, Infrared waves, Visible light (Red, Orange, Yellow, Green, Blue, Indigo, Violet) Ultraviolet, X-rays, Gamma rays |
Type of electromagnetic energy that has the shortest wave length | Gamma rays |
Type of electromagnetic energy that has the longest wave length | Radio waves |
Type of electromagnetic energy that has the highest frequency | Gamma rays |
Type of electromagnetic energy that has the lowest frequency | Radio waves |
Type of wave light is. | Transverse |
Doppler Effect (def) | Concept in which a wave is compressed as the object comes closer & the wave expands as the object moves away from the observer. |
Red Shift | If a star is moving away from the observer, the stars spectrum (fingerprint) shifts towards the red end of the spectrum |
Blue Shift | If a star is moving toward the observer, the stars spectrum (fingerprint) shifts towards the blue end of the spectrum |