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    火星上的甲烷之謎:它能代表生命嗎?

    kira86 于2019-07-05發布 l 已有人瀏覽
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    美國宇航局(NASA)表示,他們的火星探測器最近在這個星球上記錄到了高濃度的甲烷氣體。這一發現令人興奮,因為甲烷氣體的存在可以支持火星上存在生命跡象的說法。
      小E英語歡迎您,請點擊播放按鈕開始播放……

    Methane Mystery on Mars: Could It Mean Life?

    火星上的甲烷之謎:它能代表生命嗎?

    The United States space agency, NASA, says its Mars exploration vehicle recently recorded a high level of methane gas on the planet. The discovery is exciting because the presence of methane gas could support the case for life on Mars.

    美國宇航局(NASA)表示,他們的火星探測器最近在這個星球上記錄到了高濃度的甲烷氣體。這一發現令人興奮,因為甲烷氣體的存在可以支持火星上存在生命跡象的說法。

    NASA’s Curiosity vehicle recently recorded the largest level of methane ever measured during its seven-year Mars mission.

    美國宇航局的“好奇”號飛行器最近記錄了其七年來火星任務期間探測到的最大甲烷含量。

    Methane has no color or smell. A special instrument on Curiosity’s Mars Science Laboratory recorded the increased gas level. The device, called a laser spectrometer, measures levels of chemical elements and gases in the Martian atmosphere. In addition to methane, the instrument can record levels of water and carbon dioxide.

    甲烷無色無味。“好奇”號火星科學實驗室的一個特殊儀器記錄了甲烷含量的增加。這個被稱為雷射光譜儀的裝置觀測火星大氣中化學元素和氣體的含量。除甲烷外,該裝置還可以觀測水和二氧化碳的含量。

    Nearly all the methane gas found in Earth’s atmosphere is produced by biological activity. It usually comes from animal and plant life. But it can also be formed by geological processes, such as interactions between rocks and water.

    地球大氣中幾乎所有的甲烷氣體都是由生物活動產生的,通常來自動植物。但也可以通過地質作用形成,如巖石和水的相互作用。

    NASA said the increased methane was measured to be about 21 parts per billion by volume (ppbv). One ppbv means that if you take a volume of air on Mars, one billionth of the volume of air is methane.

    美國宇航局表示,測量到的甲烷的體積濃度比增加到21ppbv。1ppbv指如果你在火星上吸入1體積的空氣,那么其中十億分之一就是甲烷。

    It was not the first time Curiosity has found methane gas in the Martian atmosphere. About a year ago, NASA announced that Curiosity had discovered sharp seasonal increases in the gas.

    這并非“好奇”號第一次在火星大氣中發現甲烷。大約一年前,美國宇航局就宣布“好奇”號發現甲烷含量季節性飆升。

    This time, NASA said the measured methane gas level was clearly larger than any others observed in the past. NASA officials even temporarily stopped Curiosity’s other activities to investigate further.

    這次,美國宇航局表示,這次測量到的甲烷濃度明顯高于過去觀測到的其他任何濃度。美國宇航局官員甚至暫停了“好奇”號的其他活動,從而進行進一步的調查。

    “It’s exciting because microbial life is an important source of methane on Earth,” NASA said in a statement announcing the discovery.

    “這令人感到興奮,因為在地球上微生物是甲烷的重要來源,”美國宇航局在一份宣布其發現的聲明中表示。

    However, Curiosity’s team carried out a follow-up methane experiment that showed a sharp drop in levels of the gas. The second examination found the level was less than one part per billion by volume. That number was “close to the background levels Curiosity sees all the time,” NASA said.

    然而,“好奇”號團隊進行了后續的甲烷實驗,其結果顯示甲烷濃度急劇下降。第二次實驗發現甲烷的體積濃度比低于1ppbv。以前的論文記錄了甲烷的背景濃度如何隨季節上升和下降。

    The rise and fall of the methane gas levels left NASA scientists with more questions than answers. The scientists are continuing to study possible causes for the sudden increase.

    甲烷氣體含量的上升和下降使美國宇航局的科學家們面臨的問題多于答案??茖W家們正在繼續研究致使甲烷含量突然飆升的可能原因。

    The methane mystery continues, said Ashwin Vasavada, Curiosity’s project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. We’re more motivated than ever to keep measuring and put our brains together to figure out how methane behaves in the Martian atmosphere.

    加利福尼亞州帕薩迪納市的美國宇航局噴氣推進實驗室“好奇”號的項目科學家阿什文·瓦薩瓦達說:“甲烷之謎還在繼續。我們比以往任何時候都更有動力去不斷觀測,發揮集體智慧來弄清火星大氣中甲烷的動態。”

    Curiosity does not have instruments that can exactly identify whether the source of the methane is biological or geological. One leading theory is that methane is being released from underground areas created by possible life forms that disappeared long ago.

    “好奇”號沒有儀器能夠準確識別甲烷來源是生物的還是地質的。一個主要的理論認為甲烷是從地下釋放出來的,釋放的甲烷可能是由很久以前消失的生命形態產生的。

    Even though Mars has no active volcanoes, scientists believe it is also possible that methane is being produced by reactions involving carbon materials and water.

    盡管火星上沒有活火山,但科學家們相信甲烷也有可能是通過碳材料和水的反應產生的。

    A clearer understanding of methane levels over time “could help scientists determine where they’re located on Mars,” NASA said. Scientists hope this understanding will come as Curiosity continues to collect methane data in its search for possible life.

    美國宇航局表示,更清楚地了解甲烷含量隨著時間推移的改變“可以幫助科學家確定甲烷分布在火星上的位置”??茖W家們希望,隨著“好奇”號尋找生命跡象的過程中繼續收集甲烷數據,這種了解也會實現。

    I’m Bryan Lynn.

    布萊恩·林恩報道。

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