May 1, 2009 -- An innovative plan to retrieve comet particles from Earth's stratosphere has hit pay dirt, with the discovery that a large percentage of grains collected during a 2003 excursion predate the formation of the solar system. "It was the largest number ever found," Henner Busemann, with the University of Manchester's School of Earth, Atmospheric and Environmental Sciences, told Discovery News. The samples analyzed by Busemann and colleagues were collected by a high-altitude NASA research jet flying in April 2003 as Earth traveled through the dusty wake of Comet 26P/Grigg-Skjellerup. "This was the equivalent of sampling a meteor shower. Nobody had previously collected samples of a comet in that way," said University of Washington's Donald Brownlee, who heads a science team analyzing particles returned by the Stardust spacecraft, which flew by Comet Wild-2 in January 2004. Related Content:
Scientists believe our solar system was formed out of the exploded remains of an older star. Isotopic analysis of what are known as interplanetary dust particles, culled from meteorites and other sources, show some grains are older than the 4.5-billion-year-old solar system. Scientists don't know how long interstellar dust grains can survive space. They are made in stars and destroyed by shock waves, Brownlee said. Thousands of grains have been analyzed, but so far the richest haul of pre-solar particles appears to be from the sample collected on plastic plates covered in sticky silicon oil flown outside the NASA U2 aircraft. The Stardust team has been looking for similar particles among its samples, but so far has come up empty-handed. "All this is quite perplexing, actually," Brownlee told Discovery News. It's possible that the comets were made at different time and formed from a different variety of materials, Brownlee added, or that pre-solar grains from Wild-2 were destroyed as they were captured by the probe. "It's a mystery," said Brownlee, "but that's what makes science run." Busemann presented his findings the European Week of Astronomy and Space Science conference at the University of Hertfordshire last week. Related Links: Get More NewsSpiders, Scorpions Among World's Oldest CreaturesMany creepy crawlies have been on Earth much longer than previously believed.Blood-Sucking Vampire Bats Sing DuetsWhite-winged vampire bats "harmonize" with separated roost mates.Oldest Hebrew Writing Possibly FoundAncient inscriptions on a 3,000-year-old pottery shard could make history.Rare, Prehistoric-Age Reptile Found in N.Z.A tuatara has been spotted on the New Zealand mainland for the first time in 200 years.Iceman Has No Living RelativesOetzi, the 5,300 year-old frozen mummy, left no living genetic legacy.SLIDE SHOW: Landscapes of TerrorWhat makes a place feel scary? There are scientific explanations.It's Official: People Are Warming the PolesHumans are conclusively to blame for polar warming, say scientists.Eight-Armed Animal Preceded DinosaursWhat may be one of Earth's first animals was no bigger than a coaster and had eight arms.Phoenicians Live on in People's GenesOne in 17 Mediterranean men may be descended from ancient Phoenicians.Pesticides, Fertilizers Linked to Frog DeclineA pesticide is found to promote parasites among amphibians.Hubble Telescope Taking Photos AgainThe Hubble Space Telescope is once again snapping stunning photos of the universe.Andean Mummy Hairs Show Hallucinogen UseScientists find direct evidence of hallucinogenic drug use among ancient Andeans.Opals on Mars Reveal Planet's Long Wet PastOpals found on Mars suggest the planet has been wet for much longer. |
advertisement
|
-
our sites
-
video
mobile
-
shop
-
stay connected
-
corporate
