ASTRO-110 Lecture Notes - Lecture 15: Parsec, Elliptical Galaxy, Spiral Galaxy
18 Sep 2020
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Humason measured the shift to longer wavelengths of absorption lines in the. Using cepheid variables as a standard candles galaxy"s spectrum. The farther away a galaxy is, the faster it is moving away from us. H, the slope of the line, is called hubble"s constant (km/s per mpc) Hubble"s law does not apply to the nearest galaxies gravitational tugs from nearby galaxies cause velocities greater than the. Have the shortest range of applicability, so. We use them to calibrate the next-most accurate method, and so on until. We have built up a chain of methods for measuring the size of the. There is no center or edge of the universe. From any galaxy"s point of view, other galaxies are all moving away from it. H tells us the rate at which galaxies are moving apart from one another. So if we run the clock backward to when the galaxies were all at one point.
