時(shí)差N小時(shí):平流層細(xì)菌

Don: Nice telescope, Yael, what are you looking at?

唐：不錯(cuò)的望遠(yuǎn)鏡，雅艾爾，你在看什么?

Yale: Bacteria.

雅艾爾：細(xì)菌。

Don: In space?

唐：在太空嗎?

Yale: Not that far out, Don. Scientists recentlycollected three brand new species of bacteria fromthe Stratosphere. When I heard about it, I couldn'tbelieve it. Researchers have been using balloonlifted cryosamplers to collect bacteria and fungifrom the stratosphere for years.

雅艾爾：沒(méi)那么遠(yuǎn)，唐。最近科學(xué)家們從平流層收集到三種新的細(xì)菌品種。當(dāng)我聽(tīng)說(shuō)時(shí)，我不太相信。多年來(lái)，研究人員一直在利用氣球舉起低溫采樣器來(lái)收集大氣中的細(xì)菌和真菌。

Don: I didn't think that anything can live that high in the amosphere.

唐：我不認(rèn)為在那么高的大氣中會(huì)有生命存在。

Yale: Neither did I. The stratosphere extends from ten to thirty miles above the surface.That's above the clouds where temperatures can get as cold as minus 76 degrees Fahrenheit,and there's lots of ultra violet radiation.

雅艾爾：我以前也是。平流層位于距地表10英里至30英里的高度。那里在云端之上，溫度可低至零下76攝氏度，并且有大量的紫外線輻射。

Don: So How do they think bacteria got up there?

唐：那他們認(rèn)為細(xì)菌是如何到達(dá)那里的?

Yale: Some scientists think they ride up on particles ejected from volcanoes. Others thinkbacteria might be sucked through updrafts caused by a special kind of lightning that travelsupwards from cloud tops. Forest fires can also cause thunderstorms that toss immense plumesof smoke into the stratosphere. Bacteria could ride on the soot.

雅艾爾：有些科學(xué)家認(rèn)為細(xì)菌是由火山噴射出的粒子帶上去的。還有人則認(rèn)為，細(xì)菌也許是卷入了一種自云層頂端向上運(yùn)行的特殊閃電造成的上升氣流。森林火災(zāi)會(huì)引起雷暴，將大量濃煙擲入平流層。細(xì)菌可能會(huì)駕塵而上。

Don: And they are the same kind Of bacteria that live here on the surface?

唐：那么它們與生活在地表的細(xì)菌是同一種類嗎?

Yale: Some are known species. They have found rod-shaped Bacillus that are very commonhere as well as Staphylococcus species related to disease causing bacteria. Others arecompletely new, including two new Bacillus species. There's also a third group of bacteriafound in clumps that can't be cultured in normal bacterial nutrients. So far, they are a puzzle.

雅艾爾：有些種類是一樣的。已經(jīng)找到的有非常普遍的桿狀桿菌，還有致病細(xì)菌——葡萄球菌。 其他的則是完全未知的，包括兩個(gè)新的桿菌品種。還有第三種細(xì)菌，它們成群生長(zhǎng)，不能在平常的細(xì)菌培養(yǎng)液中培養(yǎng)。到目前為止它仍是個(gè)謎。

Don: That's really out of this world, Yael. But you really are trying to see bacteria with yourtelescope, are you?

唐：那真是不可思議，雅艾爾。但你真的在用望眼鏡觀察細(xì)菌，是嗎?

Yale: No, Don. They are away too small. I'm just out enjoying the stars.

雅艾爾：不，唐。它們太遠(yuǎn)，并且太小。我只是在觀賞星星。