Word: virgo
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Dates: during 1990-1999
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That won't be easy. The newly discovered planets are much bigger than Earth, yet it is almost impossible to learn very much about them. The stars they orbit--70 Virginis in the constellation Virgo and 47 Ursae Majoris in the Great Bear--are each about 35 light-years away. The speediest space probe would take millions of years to reach them; even a radio signal, the fastest known thing in the universe, would need 35 years to get there, and it would take another 35 for any aliens, should they exist, to answer. The planets are so dim that...
...conclusion that rather than expanding outward in a stately fashion like the rest of the universe, a collection of many thousands of galaxies, including our own and spanning a billion light-years or so, may be speeding en masse toward a point somewhere in the direction of the constellation Virgo...
That still isn't far enough out to give a direct measure of the Hubble-the cosmic rate of expansion. But M100 is part of a huge group of galaxies known as the Virgo cluster. The M100 calculation gave the astronomers the distance to Virgo, and they used that number in turn to estimate the distance to the Coma cluster of galaxies, about five times as far away. Coma, finally, is far enough out that it's a reliable indicator of the Hubble Constant. Based on Freedman's analysis, the Constant comes in at 80, indicating a universe between...
Freedman is the first to admit her team's age figures could be off 20% in either direction. The reason: no one knows whether M100 lies inside the Virgo cluster or whether it is more in the foreground or background. Astronomers have to check out other galaxies in the area before they are sure that M100 fairly measures the distance of the cluster as a whole. They're also checking galaxies outside Virgo, and while Freedman won't say what they have found so far, she told TIME that the results are "consistent" with the preliminary figures...
Several mitigating factors could prevent such a conceptual catastrophe. For one thing, the space-telescope astronomers acknowledge a significant margin of error in their calculations. It's not certain, for example, whether M100 lies right at Virgo's center or somewhere on the near or far edge. The Hubble numbers do broadly agree, however, with results announced last month by two other groups working with ground-based telescopes...