Meteor Showers bring August Fireballs
August is usually regarded as "meteor month" in the Northern Hemisphere, as one of the best shooting star displays of the year reaches its peak near midmonth. The annual Perseid meteor shower is beloved by everyone from meteor enthusiasts to summer campers. The Perseids are predicted to peak overnight on Aug. 12-13, when Earth travels through the middle of a belt of debris laid down in space by comet Swift-Tuttle. But a major obstacle, the Moon, will work against attempts to spot the fiery space dust this year. The Moon will turn full on Aug. 12, severely hampering observations just at the wrong time. Bright moonlight will flood the sky all through that entire night. three "windows" of dark skies will be available between moonset and the first light of dawn on the mornings of Aug. 8, 9 and 10 (conveniently on the weekend)."
Two University of Toronto astronomers and a U.S. colleague have made the first-ever measurements of the size and shape of massive dark matter halos that surround galaxies. "Our findings give us the clearest picture yet of a very mysterious part of our universe," says principal investigator Henk Hoekstra, a post-doctoral fellow at U of T's Canadian Institute for Theoretical Astrophysics. "Using relatively simple physics, we can get our first direct glimpse of the size and shape of these halos which are more than fifty times more massive than the light-producing part of galaxies that we can see." He and his team presented their findings July 25 at the 25th general assembly of the International Astronomical Union in Sydney, Australia."
"The search for life on other planets could soon extend to solar systems that are very different from our own, according to a new study by an Ohio State University astronomer and his colleagues. In fact, finding a terrestrial planet in such a solar system would offer unique scientific opportunities to test evolution, said Andrew Gould, professor of astronomy here. In a recent issue of Astrophysical Journal Letters, he and his coauthors calculated that NASA's upcoming Space Interferometry Mission (SIM) would be able to detect habitable planets near stars significantly more massive than the sun. Scientists have typically thought that the search for life should focus on finding planets like Earth that orbit stars like the sun, but this new finding shows that "the field is wide open," Gould said."
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