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23 Cards in this Set
- Front
- Back
Interstellar Medium |
Made up of two components: gas and dust, which is intermixed throughout all space. |
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Regions of space where (blank), blocks the light from stars beyond. Composed of hydrogen and helium. |
Interstellar Medium |
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consisting of clumps of atoms and molecules in the interstellar medium
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Interstellar Dust |
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Dust Grains |
typical interstellar dust particle |
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True or False: dusty regions of interstellar space are transparent to long wavelength radio and infrared radiation. |
True |
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Extinction |
overall dimming of starlight by interstellar medium |
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True or False: Interstellar medium is more opaque to short-wavelengths radiation than to radiation of longer wavelengths, often causing what? |
True: results in light from distant stars to being robbed of its higher frequency, blue. This leads to the reddening effect. |
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an effect where stars tend to appear redder than what they really are
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Reddening |
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What makes interstellar space a relatively dirty place? |
Dust Particles |
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using a beam of light can absorb or scatter only the particles that have a diameter comparable to or larger than the wavelength of radiation involved |
Using the effects of starlight to measure amount and size of interstellar dust. |
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Is the density of the interstellar medium high or low? |
Extremely Low. |
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Composition of interstellar gas
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Silicates, graphite and iron |
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Composition of interstellar dust |
90% of the gas is a atomic or molecular hydrogen. 9% is helium 1% consists of heavier elements. Abundances of heavy elements include carbon, oxygen, silicon, magnesium and iron. |
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What evidence best supports that interstellar dust forms out of interstellar gas? |
Composition of interstellar gas which shows elements are under-abundant in the gas |
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Dirty Ice |
frozen mixture of ordinary water contaminated with ammonia, methane, and other chemical compounds. Dirty ice is usually found in the interstellar dust. |
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Starlight provides a mean of studying particles based on the fact that light emitted by stars is dimmed partially (answer) |
Polarization |
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Nebula |
term that refers to any fuzzy patch (bright or dark) on the sky. Any region of space that was clearly distinguishable. Many (blank) are clouds of interstellar dust and gas. |
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Emission Nebulae |
glowing clouds of hot interstellar matter. |
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Dust Lanes |
Often crossed by Nebulae, part of the larger cloud which they formed.
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Caused by starlight scatted from dust particles in interstellar clouds, they appear blue for much the same blue light more easily scattered by interstellar matter. |
Reflection Nebula |
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Dark Dust Clouds |
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Dark Molecular Clouds |
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Molecular Cloud Complex |
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