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Solve : Your Speed is 73 km per second.? |
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Answer» Quote Astrophysicists Have Calculated the Speed at Which the Universe Expands theweek.com — The universe is expanding at 73.8 kilometers per second per 3.26 million light years, give or take 2.4 km, according to a study published in the Astrophysical Journal.Quote Your Speed is 73 km per second.In what reference frame?What kind of speed you are talking about?Human or vehicle?Please write details.I want to upgrade my speed. Quote So, according to this equation, a galaxy 3.26 million light years AWAY — or one megaparsec — is moving away from us at around 73.8 kilometers per second. A galaxy two megaparsecs away would be travelling twice as quickly, and so on.Your Speed is 73 km per second per megaparsec.*censored*.. so quick The title is very misleading. It isn't 73km per second, it's 74km per second per megaparsec. Additionally the value, also known as Hubble's Constant, has been highly DEBATED amongst astrophysicists due to the massive uncertainties that COME with measuring speed over such vast distances. Also that's not how fast the Earth is moving, it is how fast galaxies are moving away from Earth (using the formula V = H0 D where v is velocity, H0 is 73.8km-1mpc-1 and D is distance from Earth. I think I'm ready for my astrophysics test next month.....speed and velocity are meaningless without a reference frame. "speed per megaparsec" is more a measure of how fast you are going relative to a point some multiple of a megaparsec away. of course what the constant really measures is the difference between the velocity of observer (us) and something else a given distance away (such as a galaxy). Absolutely nothing in the entire universe is stationary, simply because there can be no definition for what is stationary except within a SMALLER reference frame. Yup. The H0 figure is the recessional speed of galaxies from Earth - i.e. relative to Earth. Incidentally, my Astro and Relativity exams are back to back. Fun stuff.That is a measure of how quickly the fabric of space itself is expanding. The galaxies are not "moving" away from each other. The universe is expanding around and between them. Galaxies do however move, just not at the rate of cosmological expansion. |
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