Word: solarity
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...turns out that our solar system is moving nearly 100,000 m.p.h. faster than previously thought - revolving around the center of the Milky Way at 568,000 m.p.h., announced Mark Reid of the Harvard-Smithsonian Center for Astrophysics on Monday at the American Astronomical Society's conference in Long Beach, Calif. Since velocity is related to mass, the 15% increase in solar-system speed translates into a near doubling of mass of the Milky Way, according to Reid's group - and all of that newfound bulk is composed of dark matter...
Original estimates of the solar system's speed were based on what Reid calls "one-dimensional velocity" obtained solely from Doppler shifts. "Now," he says, "we have three-dimensional velocity and more exact measurements" - a huge advancement in the field. The findings debunk the notion that the Milky Way is a little-sister galaxy to her neighbor Andromeda. "They're more like fraternal twins," Reid says. And the fact that they are of equal size increases the likelihood that the two will someday collide. (See the Top 50 space moments since Sputnik...
...rovers were launched atop separate boosters. Spirit left Earth on June 10, 2003, and Opportunity followed on July 7, taking advantage of the biannual close approach Mars and Earth make as they orbit the sun. On solar system scales, a close approach is still a goodly distance - 35 million miles in 2003 - which means that the rovers needed seven months to get where they were going. Spirit landed first, bouncing down in a swaddle of air bags in Mars' Gusev Crater. Opportunity followed three weeks later, landing on the other side of the planet in what is now known...
...time Opportunity arrives, Spirit may be gone. The caprice of the Martian winds has done a better job of clearing Opportunity's solar panels than Spirit's, and project manager John Callas says that although both rovers survived the past Martian winter, in Spirit's case, it was a "squeaker." The winter that will come later in 2009 could easily be its last. Of course, the same was true of the winters that came and went from 2004 to 2008. Both machines clearly inherited long life from their Sojourner granddaddy, and both seem equally determined to make the most...
Without the unerring measurement provided by atomic clocks, we couldn't have landed a rover on Mars, the Internet wouldn't be able to process data superfast and GPS navigation would be a fantasy. These clocks are so precise that they literally redefined time: Once tied to the mean solar day, the official measure of a second was changed in 1967 to refer to the duration of more than nine billion periods of radiation between two levels of the cesium 133 atom...