**古巴美国吁取消贸易禁运**
古巴领导人劳尔·卡斯特罗说，美国和古巴之间不会出现全面的关系正常化，除非美国解除贸易禁运，结束其对关塔那摩湾军事基地的“非法”占领，停止“破坏稳定”的广播，以及补偿古巴人的经济损失。
卡斯特罗主席在他在联合国大会发表的第一次讲话中说，只要封锁仍然存在，他的政府就将继续在联合国提出一项反对美国贸易禁运的决议草案。
美国总统奥巴马已经表示支持解除禁运，这一程序还将需要国会采取行动。
周一早些时候，美国总统奥巴马告诉联合国，虽然美国在人权等问题上将继续与古巴有“分歧”，但是这些差异现在将通过包括外交关系等多种渠道加以处置。
奥巴马说：“古巴的变革不会一蹴而就。”
他表示相信，“开放，而不是不强制”将“支持古巴人民应该得到的改革和生活改善。”
奥巴马总统说，他相信美国国会最终将解除贸易禁运。在他这样说时响起了掌声。
Cuba, US Call for End to Trade Embargo
A full normalization of ties between the U.S. and Cuba will not occur, says Cuban leader Raul Castro, until the U.S. lifts the trade embargo, ends its "illegal" occupation at the Guantanamo Bay military base, stops "destabilizing" broadcasts to Cuba and compensates Cubans for economic damages.
In his first ever speech at the United Nations General Assembly, President Castro said his government would continue to introduce a draft resolution against the U.S. trade embargo at the U.N. as long as the embargo remained in place.
U.S. President Barack Obama has voiced support for lifting the embargo, a procedure that would require congressional action.
Earlier Monday, President Obama told the U.N. that while the U.S. continues to have "differences" with Cuba, on issues such as human rights, these differences would now be addressed through channels that included diplomatic relations.
"Change won't come overnight to Cuba," said Obama.
Mr. Obama said he was confident that "openness, not coercion" would "support the reforms and better life the Cuban people deserve."
The president drew applause when he said he was confident that Congress would eventually lift the trade embargo.
**美国宇航局：火星上存在液态水**
美国宇航局的科学家说，他们探测到火星夏季出现“卤水流”。这一发现支持这个红色行星上可能有生命的观点。
科学家早就知道，火星上曾经有水。但是他们认为，气候变化已导致这颗行星无水。美国航空航天局的科学家星期一宣布，他们掌握的证据显示，这颗红色行星上的水比以前所认为的多。
美国宇航局天体科学部主任吉姆·格林说：“我们的探测车发现，那里的空气湿度比我们原先想象的高。土壤摄取后，变潮变湿，充满水份。”
连续几年，科学家观察到火星坡地上有看似弯弯曲曲的神秘条痕。对航空航天局探测车采集数据的全面分析表明，夏季出现的色泽较暗条痕，极有可能是一道道水流。
航空航天局火星探测部的迈克尔·迈耶说：“不过我们并不知道水到底来自何方，可能是地表之下隐藏着一个大水源，但是对此我们还一无所知，因此对这项最新发现而言，这是下一个谜团。”
五年后, 航空航天局的下一个大探测车将从火星带回样本时，有关这个问题以及其他问题的答案大约将会比较清楚。水的存在将表明，那个行星上有生命。
这将有助于未来的宇宙旅行。对此美国宇航局天科学部负责人约翰·格伦斯菲尔德说：“有水，大家知道，水是什么？就是氢氧化合物，是我们制造火箭燃料的物质。”
格伦斯菲尔德说：“借助‘好奇’号探测车，我们如今知道，火星曾是一个酷似地球的行星，有过温暖的咸海，淡水湖，或许还有白雪覆盖的山峰，云朵和水的循环。就像我们在地球上用地球科学卫星对水的循环做研究一样。不过，火星后来发生了情况，致使其水的丧失，不过火星大气和地表大部依然还存有水，只是我们依然还有疑问，火星上曾有生命出现吗？我们能够找到吗？”
航空航天局宣布上述消息前几天，新电影《火星人》发行，影片讲述了由马特·戴蒙扮演的宇航员在火星上陷入困境的故事。斯科特·里德利依据一部畅销书改编的这部科幻片，肯定会增加人们对这个行星的好奇之心。
NASA: Liquid Water Exists On Mars
Scientists at the U.S. space agency say that they have detected salty water streams appearing during summer on Mars. The finding supports the notion there may be life on the red planet.
Scientists have long known that there once was water on Mars. But they thought a change in climate had caused the planet to become arid. On Monday, NASA scientists announced they have evidence that there is more water on the red planet than previously thought.
Jim Green, NASA Director of Planetary Science, said, "Our rovers are finding that there is a lot more humidity in the air than we ever imagined. As we ingest the soils, they are moist, they're hydrated, full of water."
For several years scientists have monitored mysterious streaks on the slopes of Mars that appear to be waxing and waning. A comprehensive analysis of the data collected by NASA rovers reveals that the darker streaks showing up in the summer are most likely streams of water.
Michael Meyer, of NASA Mars Exploration, said, "But we don't know where the water actually comes from and so it could be hiding a major source of water in the subsurface. But we don't have any idea and so this is sort of the next puzzle to this recent discovery."
The answer to this and many other questions will be clearer in about five years, when the next big NASA rover brings back samples from Mars. The existence of water would indicate that there are living organisms on the planet.
It would also facilitate future space travel.
John Grunsfeld, NASA head of science, said, "When you have water ... you know, what's water? Hydrogen and Oxygen. That's what we make rocket fuel out of."
John Grunsfeld, NASA head of science, said, "From the Curiosity rover we now know that Mars once was a planet very much like earth, with warm salty seas, with fresh water lakes, probably snow kept peeks and clouds and a water cycle, just like we are studying here on earth with our earth science satellites, the water cycle here on earth. But something has happened to Mars and it lost its water, but we still have in the atmosphere and on the surface for the most part, but we still have the question, did life arise on Mars once and can we find out?"
The NASA announcement comes within days of the release of a new movie, The Martian, featuring Matt Damon as an astronaut stuck on Mars. Scott Ridley's science-fiction film, based on a best-selling book, is sure to increase curiosity about the planet.
