This artist's conception shows a young, hypothetical planet around a cool star. A soupy mix of potentially life-forming chemicals can be seen pooling around the base of the jagged rocks. Observations from NASA's Spitzer Space Telescope hint that planets around cool stars—the so-called M-dwarfs and brown dwarfs that are widespread throughout our galaxy—might possess a different mix of life-forming, or prebiotic, chemicals than our young Earth.
Life on our planet is thought to have arisen out of a pond-scum-like mix of chemicals. Some of these chemicals are thought to have come from a planet-forming disk of gas and dust that swirled around our young sun. Meteorites carrying the chemicals might have crash-landed on Earth.
Astronomers don't know if these same life-generating processes are taking place around stars that are cooler than our sun, but the Spitzer observations show their disk chemistry is different. Spitzer detected a prebiotic molecule, called hydrogen cyanide, in the disks around yellow stars like our sun, but found none around cooler, less massive, reddish stars. Hydrogen cyanide is a carbon-containing, or organic compound. Five hydrogen cyanide molecules can join up to make adenine—a chemical element of the DNA molecule found in all living organisms on Earth.
Warangler Sahara.. again.. :p, Kamsack SK Oct 29 2012
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오늘 월요일.. 우리 호텔의 레스토랑이 쉬는 날이다.
호텔의 바(술집)는 연중무휴로 열지만 레스토랑은 월요일 날 쉰다.
바는 우리 직원들인 바텐더들이 있기 때문에, 난 거의 신경을 안쓴다. 주류 재고와 돈만 챙긴다.. ㅎ
좌간, 내가 지금 주력하고 있는 레스토랑에 별일이 ...
12 years ago
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