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Researchers have discovered new clues pointing to the possibility of flowing saltwater on Mars. |
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NASA announced the finding at a news conference Thursday at the space agency's Washington headquarters. |
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研究人員發現了新線索指出火星上可能有流動的鹽水。美國太空總署週四在該太空機構的華盛頓總部記者會上宣佈了這項發現。 |
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Scientist Alfred McEwen and his team observed Mars using the HiRISE camera aboard NASA's Mars Reconnaissance Orbiter. |
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McEwen's observations were recently published in the journal Science. |
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He and his team noticed dark streaks on some planet slopes that appear to fade in the winter and come back in the spring. |
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科學家阿佛德．麥克溫和他的小組用 NASA 火星軌道探測器上的 HiRISE 攝影機觀察火星。他的觀測結果最近發表在《科學》期刊上。他和小組注意到有些行星坡上的深色條紋似乎會在冬天淡去，春天時又出現。 |
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These apparent flows happen near Mars' equator in its southern hemisphere, where temperatures are warm enough to support the presence of liquid water. |
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Because Mars orbits about 50 million miles farther from the Sun than Earth, temperatures rarely climb above the freezing mark. |
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Prior to these findings, water was believed to exist in the form of ice in Mars' polar regions, and has also been detected at mid-latitudes. |
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This is the first evidence supporting the presence of liquid water on the planet. |
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這些明顯的水流出現在火星南半球接近赤道的地方，該地區氣溫夠溫暖，足以維持液態水的出現。因為火星繞行太陽的距離比地球遠了五千萬英里左右，氣溫很少上升到冰點以上。在這些發現以前，據信水是以冰的型態存在於火星的極區，也曾經在中緯度地區測得。這是第一次有證據支持該行星上有液態水存在。 |
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Summer highs at Mars' equator can reach 70 degrees Fahrenheit (20 Celsius). |
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However, at the middle latitudes, where the observations disclosed Thursday were taken, temperatures can fluctuate considerably, from summer noon temperatures of 32°F to chilly overnight lows of -75 F (-60°C). |
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火星赤道地區的夏季高溫可達華氏七十度（攝氏二十度），但是在中緯度地區，也就是週四發表的觀測結果注意的地方，氣溫波動的幅度很大，從夏天午間的華氏三十二度到整晚寒冷的華氏負七十五度（攝氏負六十度）低溫。 |
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The Martian flows bear few similarities to bodies of water we are familiar with on Earth. |
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To begin with, scientists expect the water to be briny. |
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Past studies of Mars' surface layer have found it to be salty. |
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The small finger-like flows are nowhere near the size of major rivers on Earth. |
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They are also very narrow: just 0.5 to 5 meters, wide. |
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火星上的水流和我們所熟悉地球上的水體幾無相似處。首先，科學家預期那是鹽水。過去有關火星表面地層的研究曾發現含有鹽分。那些指頭般的小水流和地球上主要河流的規模根本不能比。那些水流還很狹窄，只有零點五到五公尺寬。 |
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In total, seven sites with possible liquid flows have been found, and 20 to 30 more possible sites have been identified. |
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Some locations contain more than 1,000 separate flows. |
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總計發現七處可能有液態水流的地方，並且確認還有二十到三十個可能的地點。某些地區包含超過一千條獨立的水流。 |
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"What makes these new observations so interesting is they occur at much lower latitudes [closer to the equator], where temperatures are much warmer and where it's actually possible for liquid water to exist," said Arizona State University geophysicist Phil Christensen, one of the scientists who studied the images beamed back from the orbiter. |
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「這些新觀測結果有趣的地方在於，它們出現在較低緯度（較接近赤道），那裡的氣溫比較溫暖，也確實有可能讓液態水存在，」亞利桑那州立大學地球物理學家菲爾．克里斯汀森表示，他是研究軌道探測器傳回的影像的其中一位科學家。 |
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