地球的生命可能已經(jīng)存在于其他行星上

科學家們認為，來自地球的生命可能已經(jīng)存在于其他行星上

There's a good chance life from Earth has already spread to other planets, scientists say - and it could have happened dozens of times.

科學家說，很有可能地球上的生命已經(jīng)擴散到了其他星球，而且這種情況可能已經(jīng)發(fā)生了幾十次。

But it wasn't humans going boldly where they haven't before - but microbes.

但并不是人類大膽地去了他們以前沒有去過的地方——而是微生物。

"Long-period comets and interstellar objects could export life from Earth by collecting microbes from the atmosphere and receiving a gravitational slingshot effect from the Earth," Harvard University astronomers Amir Siraj and Abraham Loeb write in a new paper.

哈佛大學天文學家阿米爾·西拉杰和亞伯拉罕·勒布在一篇新論文中寫道:“長周期彗星和星際物體可以通過從大氣中收集微生物，并從地球接收引力彈弓效應，從而從地球輸出生命。”

Alternatively, asteroids that hit with enough power could potentially eject matter into space, which could eventually get sucked in by another planet's gravity.

另外，如果小行星撞擊地球的能量足夠大，就有可能將物質(zhì)噴射到太空中，最終被另一顆行星的引力吸進去。

"Impacts on the surface of a planet can launch debris at above the escape speed of the planet, thereby allowing debris spread throughout the planetary system and constituting a plausible mechanism for exchanging life between planets orbiting the same star."

“對行星表面的撞擊能以高于行星逃逸速度的速度發(fā)射碎片，從而使碎片在整個行星系統(tǒng)中擴散，并構成圍繞同一恒星運行的行星之間交換生命的可能機制。”

More than 200 meteorites that have fallen to Earth have been confirmed as coming from Mars, for example. None carried life, but that's because there probably isn't any on Mars

例如，已經(jīng)有超過200顆落在地球上的隕石被證實來自火星。沒有攜帶生命，但那是因為火星上可能沒有生命。

There is on Earth however.

然而，地球上有。