研究:外星行星可能比地球更適合生命存在

Alien planets could be better suited for life than Earth: study

研究:外星行星可能比地球更適合生命存在

Earth’s oceans have made it the perfect environment for biodiversity, but a new study suggests that it may not have the best conditions in the galaxy.

地球上的海洋已經(jīng)使它成為生物多樣性的完美環(huán)境，但一項(xiàng)新的研究表明，它可能不是銀河系中條件最好的。

The study suggests that exoplanets that have “favorable ocean circulation patterns” could be better suited to support a wider range of life than Earth.

研究表明，具有“良好海洋環(huán)流模式”的系外行星，比地球更適合支持更廣泛的生命范圍。

“This is a surprising conclusion,” said lead researcher Stephanie Olson of the University of Chicago in a statement. “It shows us that conditions on some exoplanets with favorable ocean circulation patterns could be better suited to support life that is more abundant or more active than life on Earth.”

芝加哥大學(xué)的首席研究員斯蒂芬妮·奧爾森在一份聲明中說(shuō)：“這是一個(gè)令人驚訝的結(jié)論。”“這表明，在一些具有良好海洋環(huán)流模式的系外行星上，條件可能更適合比地球上更豐富或更活躍的生命。”

Olson, who presented the research at the Goldschmidt Conference in Barcelona, said that life on Earth is dependent upon the upward flow of the oceans, which brings back nutrients from the deepest part of the ocean to the top, where photosynthetic life is abundant.

奧爾森在巴塞羅那的戈德施密特會(huì)議上介紹了這項(xiàng)研究，他說(shuō)，地球上的生命依賴于海洋的向上流動(dòng)，這將營(yíng)養(yǎng)物質(zhì)從海洋的最深處帶回頂部，那里有豐富的光合作用。

“More upwelling means more nutrient resupply, which means more biological activity,” Olson added. “These are the conditions we need to look for on exoplanets.”

奧爾森補(bǔ)充說(shuō)：“更多的上升流意味著更多的營(yíng)養(yǎng)物質(zhì)的再供應(yīng)，這意味著更多的生物活動(dòng)。”“這是我們?cè)谙低庑行巧闲枰獙ふ业臈l件。”

Olson and the other researchers used a series of computer models to see which exoplanets could have the conditions for efficient ocean upswelling.

奧爾森和其他研究人員使用一系列的計(jì)算機(jī)模型，來(lái)觀察哪些系外行星有條件進(jìn)行有效的海洋上升流。

“We found that higher atmospheric density, slower rotation rates and the presence of continents all yield higher upwelling rates,” Olson said in the statement. “A further implication is that Earth might not be optimally habitable — and life elsewhere may enjoy a planet that is even more hospitable than our own.”

奧爾森在聲明中說(shuō)：“我們發(fā)現(xiàn)，較高的大氣密度、較低的自轉(zhuǎn)速率和大陸的存在，都會(huì)產(chǎn)生較高的上升流速率。”“另一個(gè)暗示是，地球可能不是最適宜居住的——而其他地方的生命，可能會(huì)享受一個(gè)比我們自己更宜居的星球。”

Georgia Institute of Technology assistant professor Chris Reinhard, who was not involved in the study, said that researchers expect oceans “to be important in regulating some of the most compelling remotely detectable signs of life on habitable worlds,” but added that the understanding of oceans beyond the solar system “is currently very rudimentary.”

佐治亞理工學(xué)院的助理教授克里斯·萊因哈德(Chris Reinhard)沒(méi)有參與這項(xiàng)研究。他說(shuō)，研究人員預(yù)計(jì)海洋“在調(diào)節(jié)可居住世界上一些最引人注目的、可遠(yuǎn)程探測(cè)到的生命跡象方面很重要”，但補(bǔ)充說(shuō)，對(duì)太陽(yáng)系之外的海洋的理解“目前非常初級(jí)”。

It’s highly likely that oceans are common throughout the Milky Way galaxy. NASA’s Kepler space telescope and other instruments have suggested that one in four stars hosts an Earth-like planet, but with current technology limitations, these exoplanets have to be studied from afar.

很可能整個(gè)銀河系都有海洋。美國(guó)國(guó)家航空航天局開普勒太空望遠(yuǎn)鏡和其他儀器表明，四分之一的恒星擁有類似地球的行星，但由于目前的技術(shù)限制，這些系外行星必須從遙遠(yuǎn)的地方進(jìn)行研究。

Despite these constraints, Olson’s hypothesis, which Reinhard called “a significant and exciting step forward,” is that it’s expected that life “is almost certainly more common than ‘detectable’ life.

盡管有這些限制，萊因哈德稱奧爾森的假設(shè)是“一個(gè)重要而令人興奮的進(jìn)步”，即人們預(yù)期生命“幾乎肯定比‘可檢測(cè)’的生命更普遍”。

“This means that in our search for life in the Universe, we should target the subset of habitable planets that will be most favorable to large, globally active biospheres because those are the planets where life will be easiest to detect–and where non-detections will be most meaningful,” Olson said.

“這意味著，在我們尋找宇宙生命的過(guò)程中，我們應(yīng)該瞄準(zhǔn)那些——對(duì)大型的全球活躍的生物圈——最有利的可居住行星的子集，因?yàn)檫@些行星是生命最容易被探測(cè)到的，而非探測(cè)最有意義的行星。”奧爾索說(shuō)。N說(shuō)。

Recently, data from NASA’s Spitzer Space Telescope gave scientists the first glimpse into conditions on the surface of a rocky exoplanet, Planet LHS 3844b. The exoplanet, which is 48.6 light-years from Earth and has a radius 1.3 times that of Earth, according to NASA, is orbiting a small star called an M dwarf. It was first spotted by NASA’s Transiting Exoplanet Satellite Survey in 2018.

最近，來(lái)自美國(guó)宇航局斯皮策太空望遠(yuǎn)鏡的數(shù)據(jù)，讓科學(xué)家們第一次看到了巖石系外行星LHS 3844B的表面狀況。據(jù)美國(guó)宇航局稱，這顆外行星距離地球48.6光年，半徑是地球的1.3倍，正在圍繞著一顆叫做M矮星的小恒星運(yùn)行。2018年，美國(guó)國(guó)家航空航天局的凌日系外行星衛(wèi)星調(diào)查中，首次發(fā)現(xiàn)了它。

Though NASA’s search for life has largely focused on planets that are in the “habitable zone,” the space agency recently announced that it would explore Jupiter’s icy moon Europa to see if it “could harbor conditions suitable for life.”

盡管美國(guó)宇航局對(duì)生命的探索主要集中在“可居住區(qū)”內(nèi)的行星上，但宇航局最近宣布，它將探索木星冰冷的衛(wèi)星歐羅巴，看看它是否“能夠擁有適合生命的條件”。