Term
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Definition
these galaxies are moving away from us and that the farther away they are,
the faster they are moving. |
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Term
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Definition
longest wavelengths
low energy |
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Term
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Definition
shortest wavelengths
highest energy |
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Term
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Definition
| depending upon whether the light source is standing still or moving |
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Term
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Definition
| the wavelengths of the ripples in front of the boat shorten, while the wavelengths of the ripples behind the boat become longer |
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Term
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Definition
if all you could see were the ripples in the water, you
could tell whether the moving object is moving toward you or away from
you. |
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Term
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Definition
| diffracts light; that is, it splits and spreads out light into a spectrum. |
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Term
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Definition
contain
10 000 slits per centimetre are common and allow the precise measurements
of wavelengths of light.
The greater the number of slits in a
grating, the sharper the image. |
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Term
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Definition
| a movement of the spectral lines into the longer wavelengths of the red end of the visible spectrum |
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Term
| beginning point, or time zero |
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Definition
currently accepted as being 13.7 billion years ago;
all the matter and energy in the universe were packed together into one
immeasurably dense, hot mass |
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Term
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Definition
From this point of origin, an enormous fireball
hurled everything outward in a “big bang |
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Term
| Cosmic Background Explorer (COBE) |
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Definition
satellite found very
slight differences in the temperature of the cosmic microwave background
radiation |
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Term
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Definition
| regions of different densities, representing the distribution of matter and energy in the early universe before the stars and galaxies condensed out of the Big Bang. |
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Term
| Wilkinson Microwave Anisotropy Probe (WMAP) |
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Definition
| confirmed the age of the universe to be 13.7 billion years ±200 million years. |
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Term
|
Definition
| helped scientists pinpoint when the first stars formed and have provided clues about the first trillionth of a second of the universe. |
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