Universal expansion recalibrated

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brian livesey
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Joined: Mon Jan 09, 2006 11:05 am
Location: Lancashire

Universal expansion recalibrated

Post by brian livesey »

We'd better hold on to our hats! A research team, led by Professor Adam Riess at Johns Hopkins University, has discovered that the Universe is expanding at some nine per cent faster than was thought. The new measurement could force astrophysicists to revise their theories of universal expansion.
To obtain the new measurement, the team analysed light from 70 Cepheid variables in the biggest of the Milky Way's satellite galaxies, the Large Magellanic Cloud. A new method of observation allowed them to obtain rapid images of the Cepheids, saving the team observation time.
The conventional method for measuring star distances with the Hubble Space Telescope is time-consuming, as the instrument can only observe one star per 90-minute orbit around the Earth, A new "drift and shift" method of observation uses Hubble as a "point and shoot" camera to observe whole groups of Cepheids. These variable stars vary in brightness at regular intervals, which allows for measuring intergalactic distances.
The new data is published in "The Astrophysical Journal Letters".
Last edited by brian livesey on Mon Jun 03, 2019 10:18 am, edited 1 time in total.
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Re: Universal expansion recalibrated

Post by Cliff »

I'm not sure what the score ie now but I assume with all the problems using modern computers eg rising cost of "improving" railways, I recall that UK drivers used to be allowed to go up to 10% faster than the official speed limit. Now from what I see drivers go a lot faster than that. So I think a 9% error related to the speed of expansion of the Universe is not bad at all. In fact the Universe is so big I suspect there are quite a few differences to what theorists calculate here and there.
Best of luck from Cliff
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