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Edwin powell hubble8/9/2023 Some offices heldĪstronomical Society of the Pacific, President, 1933. Royal Astronomical Society, Gold medal, 1940, presented by H.C. Other awardsįranklin Institute, Benjamin Franklin Medal, 1939. Presentation of Bruce medalīabcock, H.D., PASP 50, 87-96 (1938). Slipher’s measurements of their redshifts, and in 1929 Hubble published the velocity-distance relation which, taken as evidence of an expanding Universe, is the basis of modern observational cosmology. (He had earlier classified galactic nebulae.) Hubble measured distances to galaxies and with Milton L. His investigation of these and similar objects, which he called extragalactic nebulae and which astronomers today call galaxies, led to his now-standard classification system of elliptical, spiral, and irregular galaxies, and to proof that they are distributed uniformly out to great distances. In 1923 - 25 he identified Cepheid variables in “nebulae” NGC 6822, M31, and M33 and proved conclusively that they are outside the Galaxy, thus demonstrating that our Galaxy is not the Universe. Wilson and Palomar Observatories in 1948. After obtaining his doctorate he spent his career, aside from army service in both world wars, at Mt. He taught high school for a year in Indiana and then returned to Chicago’s Yerkes Observatory and astronomy. The Hubble Space Telescope is continuing the work begun by Hubble himself to map our Universe, and producing the most remarkable images of distant galaxies ever seen, many of which are available via the World Wide Web.A native of Missouri, Edwin Hubble earned his bachelor’s degree at the University of Chicago, won a Rhodes scholarship, and earned a law degree at the University of Oxford. Today his name carried by the best telescope we have, not on Earth, but a satellite observatory orbiting our planet. Hubble made his great discoveries on the best telescope in the world at that time - the 100-inch telescope on Mount Wilson in southern California. And so the modern science of cosmology was born. Within General Relativity, the theory of gravity proposed by Albert Einstein in 1915, the inescapable conclusion was that all the galaxies, and the whole Universe, had originated in a Big Bang, thousands of millions of years in the past. Galaxies are receding from us, and one another, as the Universe expands. Since then much improved data has shown the conclusion to be a sound one. The observational data available to Hubble by 1929 was sketchy, but whether guided by inspired instinct or outrageous good fortune, he correctly divined a straight line fit between the data points showing the redshift was proportional to the distance. Though our ears can hear the change of pitch of the racing car engine our eyes cannot detect the tiny red-shift of the light, but with a sensitive spectrograph Hubble could determine the redshift of light from distant galaxies. Just as a sound of a racing car becomes lower as it speeds away from us, so the light from a galaxy becomes redder. The speed with which a galaxy was moving toward or away from us was relatively easy to measure due to the Doppler shift of their light. Hubble was able to measure the distances to only a handful of other galaxies, but he realised that as a rough guide he could take their apparent brightness as an indication of their distance. It had to be a separate galaxy, comparable in size our own Milky Way but much further away. In 1924 Hubble measured the distance to the Andromeda nebula, a faint patch of light with about the same apparent diameter as the moon, and showed it was about a hundred thousand times as far away as the nearest stars. It was known that some spiral nebulae (fuzzy clouds of light on the night sky ) contained individual stars, but there was no consensus as to whether these were relatively small collections of stars within our own galaxy, the ' Milky Way' that stretches right across the sky, or whether these could be separate galaxies, or 'island universes', as big as our own galaxy but much further away. In the early 1920s Hubble played a key role in establishing just what galaxies are. It was only some time after he returned to the US that he decided his future lay in astronomy. He won a Rhodes scholarship to Oxford where he studied law. At university too he was an accomplished sportsman playing for the University of Chicago basketball team. He was more remarkable for his athletic ability, breaking the Illinois State high jump record. His family moved to Chicago in 1898, where at High School he was a promising, though not exceptional, pupil. The explanation is simple, but revolutionary: the Universe is expanding. In 1929 he showed that galaxies are moving away from us with a speed proportional to their distance. Biography Edwin Hubble was a man who changed our view of the Universe.
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