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schlaugh
2008-Aug-19, 08:23 AM
The Struggle to Measure Cosmic Expansion (http://www.nytimes.com/2008/08/19/science/space/19hubble.html)

Nice and relatively lengthy piece in The Times about ongoing work taking place to establish the Hubble constant with more precision:


Hoping to understand why the universe seems to be coming apart at its seams, a young astronomer and his colleagues have embarked on one of the oldest quests in cosmology, to measure how fast the universe is growing, how big it is and how old it is.

That information is encoded in the value of an elusive number known as the Hubble constant that has led astronomers on a merry chase for three-quarters of a century. “It is the most fundamental number in cosmology,” said Adam Riess, 38, an astronomer at the Space Telescope Science Institute and Johns Hopkins University (http://topics.nytimes.com/top/reference/timestopics/organizations/j/johns_hopkins_university/index.html?inline=nyt-org), and one of the discoverers 10 years ago that some kind of “dark energy” is speeding up the expansion of the universe.


This spring, in what he called “a triumph of metrology,” Dr. Riess announced that he and his comrade, Lucas Macri of the University of Texas (http://topics.nytimes.com/top/reference/timestopics/organizations/u/university_of_texas/index.html?inline=nyt-org), had used the Hubble Space Telescope (http://topics.nytimes.com/top/news/science/topics/hubble_space_telescope/index.html?inline=nyt-classifier) to make the newest and most precise measurement yet of this parameter.

GOURDHEAD
2008-Aug-19, 01:20 PM
Isn't it about time to rename it: "the coefficient of cosmological expansion"? The mainstream seems to think of it as a variable .

Celestial Mechanic
2008-Aug-19, 03:02 PM
Isn't it about time to rename it: "the coefficient of cosmological expansion"? The mainstream seems to think of it as a variable .Agreed. I try to always refer to it as the Hubble parameter.