an important discovery has been made concerning the possible
1 of
2 available to the early earth. scientists led by sandra pizzarello, a research professor in asu's department of chemistry and biochemistry, found that the sutter's mill
3（陨星）, which exploded in a blazing fireball over california last year, contains organic molecules not
4 found in any
5. these findings suggest a far greater availability of extraterrestrial organic molecules than previously thought possible, an inventory that could indeed have been important in
6 evolution and life itself. the work is being published in this week's
7 of the national academy of sciences. the paper is titled "processing of
8 organic materials as a possible
9 of early molecular evolution in planetary environments," and is co-authored by pizzarello,
10 lynda williams, nmr specialist gregory holland and graduate student stephen davidowski, all from asu.
coincidentally, sutter's mill is also the gold discovery site that led to the 1849 california gold rush. detection of the falling meteor by doppler weather
11 allowed for rapid recovery so that scientists could study for the first time a
12 meteorite with little exposure to the elements, providing the most
13（原始的） look yet at the surface of primitive
14.
"the analyses of meteorites never cease to surprise you ... and make you wonder," explains pizzarello. "this is a meteorite whose organics had been found altered by heat and of little appeal for bio- or prebiotic chemistry, yet the very solar system processes that lead to its
15 seem also to have brought about novel and complex molecules of definite
prebiotic（生命起源以前的） interest such as polyethers."
pizzarello and her team hydrothermally treated fragments of the meteorite and then detected the compounds released by gas chromatography-mass spectrometry. the hydrothermal conditions of the experiments, which also
16 early earth settings (a
17 to
18 activity and impact craters), released a complex mixture of oxygen-rich compounds, the probable result of oxidative processes that occurred in the parent body. they include a variety of long chain linear and branched polyethers, whose number is quite
bewildering（使人困惑的）.
this addition to the inventory of organic compounds produced in extraterrestrial environments furthers the
19 of whether their delivery to the early earth by comets and meteorites might have aided the molecular evolution that preceded the origins of life.
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