Word: huchra
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...People go up against Einstein's general theory almost every day in an effort to prove it right or wrong, but the number of really accurate tests is small," said John P. Huchra, professor of astronomy and associate director of the Harvard observatory...
...study is not the first to see dark voids and large conglomerations of galaxies, but it is by far the most comprehensive. The reason no one had done such a search earlier, says Huchra, is that galaxy mapping is extremely time consuming. Their survey of 4,000 galaxies took about 1,000 hours of telescope time...
...Huchra, who made the telescopic observations for the Harvard-Smithsonian team, used an instrument called a spectrograph to break down each galaxy's light into its constituent colors. Within the spectrum he could see lines representing various elements in and around the galaxy's stars. These lines appear to be shifted toward the red end of the spectrum, depending on how fast the galaxy is moving and thus how far away from earth it is. By carefully measuring the degree of red shift, Huchra and Geller calculated the relative positions of the galaxies...
...particular, some scientists speculate that cold dark matter caused galaxies to form into the kind of bubbles Geller and Huchra have found. The process supposedly got under way 10 billion to 20 billion years ago, when the universe began with the Big Bang and the energy from that explosion started to condense into matter. Since then, ordinary visible matter, by itself, has probably not had time to gather into enormous structures. But cold dark matter may have condensed first, and its gravitational force could have helped pull visible matter into bubbles and galaxies. In fact, recent computer simulations at Princeton...
CREDIT: M.J. GELLER, J.P. HUCHRA, E. FALCO, R.K. MCMAHAN...