| Measuring
stellar distances |
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| Derived
from parallax |
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| - apparent angular shift of a nearby star relative to |
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| more distant stars as observer’s point of
view changes |
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| = Earth orbits Sun (need very large separation of views) |
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| Parallactic angle = parallax = ˝ x apparent shift |
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| (1 parsec = distance at which parallax
= 1 arcsec) |
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| • | proper motion -- nearby stars appear to
move faster |