Official Nonrev happy thoughts T shirt

Official Nonrev happy thoughts T shirt

One advantage of the numerous distance-measuring schemes in use, which overlap over a range of Official Nonrev happy thoughts T shirt from nearby to very distant, is that astronomers can calibrate and corroborate their measurements with multiple approaches. Such calibrations and corroborations thus lend an additional measure of reliability to these schemes. Indeed, by comparing results using different methods, weaknesses have been identified in certain schemes. In most cases, additional studies have demonstrated ways to guard against and correct for known difficulties. As a single example of these multiple approaches, prior to 2011 the distance to the Pinwheel Galaxy was determined, based on measurements of Cepheid variable stars in the galaxy, to be 20.9 million light-years, with an uncertainty of 1.8 million light-years. As of September 2011, measurements of the light output of the 2011 Type Ia supernova in the Pinwheel Galaxy are completely consistent with this distance figure…. In short, distances to astronomical objects can be and have been measured with substantial accuracy and reliability. For the most part, the calculations involved employ only basic mathematics taught in high school. Thus the overall conclusion of a universe consisting of billions of galaxies, most of them many millions of light-years away, is beyond reasonable doubt at the present time..

()

Official Nonrev happy thoughts T shirt, Hoodie, Sweater, Vneck, Unisex and T-shirt

Best Official Nonrev happy thoughts T shirt

The description from Richard Muller quoted in the question is a simplification of reality meant to help people better visualize how the Official Nonrev happy thoughts T shirt of spacetime works. In reality the galaxies are moving through spacetime in a complex fashion, based on the combination of all the forces acting on them, primarily the gravity of nearby galaxies and galaxy clusters. In the case of the Milky Way and Andromeda, these two galaxies are part of a gravitationally bound cluster of galaxies, called the Local Group. The dominant force that determines the movements of objects within the cluster is the combined gravitation of all the mass in the cluster, and not the expansion of spacetime. In other words, the gravitational attraction that the Milky Way and Andromeda have for one another that is drawing them together is stronger than the expansion of spacetime between them that would otherwise push them apart, and thus attraction wins and the two galaxies are on a collision course. In the same vein, the gravitational force that holds the earth in orbit around the sun is stronger than the expansion of spacetime between the earth and the sun (the expansion of spacetime at that distance being very small), and so the earth’s distance from the sun is not increasing for that reason. Likewise you are not flying apart because the molecular bonds holding the atoms in your body together are stronger than the minuscule expansion of spacetime between them in your body. The Local Group as a whole, however, is moving away from other galaxies and galaxy clusters to which it is not gravitationally bound, due to the expansion of spacetime.

()