Stars/Composition of Stars
The two most abundant elements in stars are...
Hydrogen and Helium.
Size, temperature, and the distance from us all depend on what?
the brightness of a star
The universe is...
finite and expanding
Light emitted from a star or galaxy ca be separated into a banf of colors, called...
a spectrum
How is the Doppler effect used in cosmology?
The Doppler effect is used to measure the speed at which stars and galaxies are approaching or receding from us, in a mechanism named red shift or blue shift.
When two atoms band together to make one heavier atom. The process releases large amounts of energy.
Nuclear Fusion.
Apparent Magnitude is...
how bright is a star when viewed from Earth. A vary large, hot star could look dim just because it is so far away. (how bright we see it)
All matter, energy, and space...
was once squeezed into a very small volume.
How is a redshift similar to a police car driving by?
The farther away the police car gets the longer the sound waves. The farther away a galaxy gets the longer the light waves.
If sound waves are closer together...
it has a high frequency sound
Scientists determine the composition of stars by...
studying the visible spectrum of light that comes from a star.
Absolute Magnitude is...
the amount of light that is actually given off by a star. (how bright it actually is)
How old is the Universe?
13.7 billion years ago.
Think of it in sound terms, red colors are low notes and blue colors are...
high notes
If sound waves are farther apart...
it has a low frequency sound
What is a spectroscope
a spectroscope breaks light apart and shows the wavelength of the light.
Light Year is...
the distance that light can travel in one year. 5,865,696,000,000 miles.
Edwin Hubble discovered an electromagnetic property called Red Shift in 1929. What is redshift?
When the wavelength of the light is stretched, so the light is seen as 'shifted' towards the red part of the visible spectrum.
Space is actually expanding causing the...
galaxies to move with it.
Redshift supports...
the Big Bang Theory because it provides evidence that the universe is expanding
Order the colors hottest to coldest.
blue, white, yellow, orange, and red.
Astronomical Unit is...
the distance between the sun and the earth (93 million miles)
What percent makes up the heavier elements?
1%
What lead Hubble to conclude that the galaxies are moving apart from each other?
the shift is the absorption lines of galaxies
What is the Doppler Effect?
the change in frequency of a wave in relation to an observer who is moving relative to the wave source