中文提纲：与其它类似仪器有什么不同a. 地球上用不用这样的仪器？有什么区别？b. 与之前的火星车比较c.功能、原理、性能指标等（a）地球上基本不用这种探测仪，因为地球表面上已经证实有水，即使是干枯的沙漠地表也存在大量水分子。
而DAN主要是探测地表2米以内的土壤和矿物质是否存在水分子，所以这在地球上是不需要用到这种高科技而又昂贵的探测设备。
（b）关于火星上水的探测主要有：（1）2005年8月12日，NASA发射的火星侦查轨道器（Mars Reconnaissance Orbiter, MRO）；（2）2007年8月4日，欧空局发射凤凰号火星登陆器（the Phoenix Mars Lander）；（3）2012年8月6日着陆的美国（NASA）的“好奇”号火星车。
（c）原理，功能，性能的比较：火星侦查轨道器（MRO）探测水存在的原理是：利用装备在其上的高分辨率成像科学设备（HiRISE），背景摄影机（CTX），火星彩色成像机（MARCI）和浅地层雷达（SHARAD）来探测火星上水资源。
MRO的目标包括确定液态水是否曾经在火星表面长时间存在——其他的任务已经收集到了流淌的液态水的证据，但是这样的液态水是否存在了足够长时间以令生命有机会得以演化呢？凤凰号火星登陆器（the Phoenix Mars Lander）探测原理是：凤凰号用其机械臂铲了一些土送入仪器,在一份样品的最初加热周期中，凤凰号携带的热蒸发分析仪（TEGA）探测到了水蒸气。
当凤凰号探测器的一条支架被摄入影像时，科学家发现似乎上面有随时间增长的水珠——液态水的水珠！如果凤凰号发现了液态水，它将推翻长期存在的理论——原有理论认为在火星稀薄的大气层和极寒的温度下，不会有液态水存在于地表。
好奇号（Curiosity）上装备的动态中子反照率探测器。
它安装在“好奇”号主车身背部附近，用于寻找火星地下的水冰以及晶体结构中含有水分子的矿物。
这台仪器可向火星地表发射中子束，然后记录中子束的散射速度。
氢原子可以延缓中子的速度，如果大量中子速度迟缓，便说明地下可能存在水或者冰。
这一由俄罗斯航天署提供的探测器能够发现火星地表下50厘米以内的氢原子。
NASA的下一个火星任务将会是MAVEN轨道器，计划2013年发射。
MAVEN的全称是The Mars Atmosphere and Volatile EvolutioN，将会是第一个着力于研究火星高层大气的轨道器。
MAVEN将会帮助科学家理解太阳风与火星大气层的相互作用，以及火星大气的损失是如何随时间影响火星的气候的。
理解火星是如何损失其大气,也将帮助确定该行星是怎样失去水的——这将成为搜寻其曾存生命迹象的必要线索。
Abstract：As we all known that water resources organisms are based on survival, therefore, it is necessary to detect the presence of Martian water molecules.So many rovers and the Mars probe are equipped with detect water molecules devices,for example, the "curious" is equipped with dynamic albedo of neutron detector to help us find water molecules on mars.Dynamic albedo of neutron detector is installed in the near the back of the main body named "curious".It is used to find minerals contain water molecules in the Martian underground water ice as well as the crystal structure .It can the pulsed neutron generator capable of detecting water ice and minerals, and search within two meters below the surface layer of water and ice.Body：(a)The distinction of water molecules detector between on Earth and Mars.Earth does not need this water molecule detector, since the earth's surface is easy to find the water molecules.DAN detection within two meters of surface soil and minerals, whether the presence of water molecules on Earth, so this is not necessary to use this high-tech and expensive detection equipment.(b)About water on Mars exploration activities.(1) On August 12, 2005, NASA launched the Mars Reconnaissance Orbiter (Mars Reconnaissance Orbiter, MRO); (2) In 2007, ESA launched Phoenix Mars Lander (the Phoenix Mars Lander); (3) United States (NASA), August 6, 2012 landing "curiosity" rover.(c)Principle, function, performance comparison.(1)The principle of Mars Reconnaissance Orbiter (MRO) to detection ofwater molecules: the use of equipment in the High Resolution Imaging Science on equipment (HiRISE), background Camera (CTX) the Mars color imaging machine (MARCI) and the shallow strata radar (to SHARAD)to probe Mars water resources.MRO's goals include finding liquid water ever exist at the surface of Mars for a long time. Other tasks have collected evidence of liquid water flowing, liquidwater exists long enough to make life a chance to be the evolution?(2) The principle of the Phoenix Mars Lander to detection of water molecules: Phoenix used its robotic arm shovel some soil to the instrument, a sample of the first heating cycle, the Phoenix carried by thermal evaporation Analyzer (TEGA) detected water vapor. When the Phoenix spacecraft a bracket intake image, the scientists found that it seems that the above liquid water drops of water to grow over time.(3) The principle of the Dynamic albedo of neutron detector: It is installed in the "curious" near the back of the main body, is used to find the Martian underground water ice, and the crystal structure of minerals containing water molecules. This instrument can be emitted neutron beam to the surface of Mars, and then record the speed of the neutron beam scattering. Hydrogen atoms can delay the speed of the neutron, if a large number of neutrons so slow, it underground may be the presence of water or ice. Detectors provided by the Russian Space Agency, the hydrogen atoms can be found within 50 cm under the surface of Mars.(4).NASA's next mission to Mars will the MA VEN orbiter, plans to launch in 2013. The MA VEN full name is The Mars Atmosphere and V olatile EvolutioN, will first focus on the study of Mars senior atmosphere orbiter. MA VEN will help scientists to understand the interaction between the solar wind and the Martian atmosphere, as well as the loss of the Martian atmosphere which is how over time affect the climate of Mars. If we can understand how Mars is losing its atmosphere, which will also help determine how the planet is losing water ,and which will become the search had to deposit the necessary clues for signs of life.Conclusion：To sum up, view from Mars probe launched nearly a decade, most detectors are equipped to explore the Martian surface water molecules device, and the performance and accuracy of detection equipment has been greatly improved. The DAN which is boarded the Curious is a high-tech water molecules detectors .It can achieve emitting neutrons to the Martian surface which can used to find minerals contain water molecules in the Martian underground water ice as well as the crystal structure while the Mars Rover moving on Mars.。