Friday, 8 March 2013

Universe Measured More Accurately Than Ever Before

New Results Pin Down Distance to Galaxy Next Door


This artist's impression shows an eclipsing binary star system. As the two stars orbit each other they pass in front of one another and their combined brightness, seen from a distance, decreases. By studying how the light changes, and other properties of the system, astronomers can measure the distances to eclipsing binaries very accurately. A long series of observations of very rare cool eclipsing binaries has now led to the most accurate determination so far of the distance to the Large Magellanic Cloud, a neighboring galaxy to the Milky Way and crucial step in the determination of distances across the Universe. (Credit: ESO/L. Cal├žada)
Mar. 4, 2013 — After nearly a decade of careful observations an international team of astronomers has measured the distance to our neighbouring galaxy, the Large Magellanic Cloud, more accurately than ever before. This new measurement also improves our knowledge of the rate of expansion of the Universe -- the Hubble Constant -- and is a crucial step towards understanding the nature of the mysterious dark energy that is causing the expansion to accelerate. The team used telescopes at ESO's La Silla Observatory in Chile as well as others around the globe. These results appear in the 7 March 2013 issue of the journal Nature.

Astronomers survey the scale of the Universe by first measuring the distances to close-by objects and then using them as standard candles [1] to pin down distances further and further out into the cosmos. But this chain is only as accurate as its weakest link. Up to now finding an accurate distance to the Large Magellanic Cloud (LMC), one of the nearest galaxies to the Milky Way, has proved elusive. As stars in this galaxy are used to fix the distance scale for more remote galaxies, it is crucially important.
More - Link http://www.sciencedaily.com/releases/2013/03/130306134016.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fspace_time+%28ScienceDaily%3A+Space+%26+Time+News%29&utm_content=Yahoo!+Mail

Sources: European Southern Observatory (ESO), ScienceDaily.com .

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