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There are still no signs of little green men， but NASA has got the proof of recent flowing liquid water on Mars. These findings increase the possibility that there is life on the Red Planet.
A new study published in the journal Nature Geoscience（《自然地理科学》）shows that Earth’s next-door neighbor has drops of salty water that were wet， as recently as last year. This is not the first discovery of water on Mars. Scientists proved in 2008 that the Red Planet has frozen water. Now NASA’s Mars Reconnaissance Orbiter（火星勘察轨道卫星） has found the strongest evidence yet that salt water in liquid form drops down on Mars each summer， according to the researchers. Mars is now the only planet in our solar system to show signs of water on its surface， other than our own.
“Mars is not the dry planet that we thought of in the past，” said Jim Green， director of planetary science for NASA. “Under certain conditions， liquid water has been found on Mars.”
Mysterious streaks
Five years ago， researchers found dark narrow streaks on Mars’s surface that tend to appear and grow during the warmest Martian months and fade the rest of the year. The streaks looked like signs of liquid water， but it could also be dust. Scientists used the Mars Reconnaissance Orbiter examine the sign. The spacecraft found perchlorate.
The study’s lead author， Lujendra Ojha， thought that something must be moistening Mars’s perchlorate—and that it must be liquid water.
Life beyond Earth？
Because liquid water is necessary for life， the findings suggest “that it would be possible for there to be life today on Mars，” NASA’s science mission chief， John Grunsfeld， said at a news conference.
Ojha， however， points that the salty water found by his team would not be a good home for living creatures， since perchlorates are toxic. He said the best way for now to see if there is life on Mars is to collect rocks and soil for study on Earth. A U.S. lander set in 2020 will do just that.
Vocabulary
streak n. 条纹
fade v. 逐渐消失
perchlorate n. 高氯酸盐
moisten v. 弄湿，使……潮湿
toxic adj. 有毒的
（What is your opinion about the findings？）
A new study published in the journal Nature Geoscience（《自然地理科学》）shows that Earth’s next-door neighbor has drops of salty water that were wet， as recently as last year. This is not the first discovery of water on Mars. Scientists proved in 2008 that the Red Planet has frozen water. Now NASA’s Mars Reconnaissance Orbiter（火星勘察轨道卫星） has found the strongest evidence yet that salt water in liquid form drops down on Mars each summer， according to the researchers. Mars is now the only planet in our solar system to show signs of water on its surface， other than our own.
“Mars is not the dry planet that we thought of in the past，” said Jim Green， director of planetary science for NASA. “Under certain conditions， liquid water has been found on Mars.”
Mysterious streaks
Five years ago， researchers found dark narrow streaks on Mars’s surface that tend to appear and grow during the warmest Martian months and fade the rest of the year. The streaks looked like signs of liquid water， but it could also be dust. Scientists used the Mars Reconnaissance Orbiter examine the sign. The spacecraft found perchlorate.
The study’s lead author， Lujendra Ojha， thought that something must be moistening Mars’s perchlorate—and that it must be liquid water.
Life beyond Earth？
Because liquid water is necessary for life， the findings suggest “that it would be possible for there to be life today on Mars，” NASA’s science mission chief， John Grunsfeld， said at a news conference.
Ojha， however， points that the salty water found by his team would not be a good home for living creatures， since perchlorates are toxic. He said the best way for now to see if there is life on Mars is to collect rocks and soil for study on Earth. A U.S. lander set in 2020 will do just that.
Vocabulary
streak n. 条纹
fade v. 逐渐消失
perchlorate n. 高氯酸盐
moisten v. 弄湿，使……潮湿
toxic adj. 有毒的
（What is your opinion about the findings？）