30 million years error of 1 second! Secrets of cold atomic clocks |
Temple on the second temple on the second space | atomic clocks _ news
Xinhua News Agency, Shanghai, September 17 (reporter Wang Linlin)-successful launch of the temple on the second carry a variety of sophisticated scientific equipment. Among them, developed by the Chinese Academy of Sciences, Shanghai Institute of optics "time God stitch"--space cold atomic clocks, are expected to achieve ultra-high precision error of 1 second about 30 million years, this will be the world's first on-orbit space cold atomic clock running and carrying out scientific experiments, is currently the highest precision atomic clock in space.
Development of human society is inseparable from the precise measurement of time. Prior to the space thermal atomic clocks atomic clocks are running in precision and maximum error of 1 second corresponds to 3 million years. This time, by Temple on the second carry of space laser cooled cold atomic clock technology into space in the microgravity environment of space, further enhance the time accuracy 10 times, means that the clock will run 30 million years have error of 1 second!
So accurate clocks has what effect? Director of the Chinese Academy of Sciences, Shanghai Institute of optics and quantum optics laboratory Liuliang introduced in space, space cold atomic clocks, ultra high-precision time and frequency reference can be established. With this baseline, you can put the other atomic clocks in sync in the sky, global satellite navigation systems with more accurate and stable running capabilities.
In addition, development of atomic technology will also significantly improve the accuracy of many experiments, experiments make it impossible become possible. For example, deep space navigation. Liuliang said, if our solar system not affected by gravitational Lagrangian point place a cold atomic clocks, humans can move beyond near-Earth scope, in the solar system within the context of this larger achieve accurate positioning, carried out a large-scale temporal and spatial studies, including whether general relativity at large scales, and so on.
As another example, cold-Atom interferometers can take the place of space Laser Interferometer Space, achieved on-orbit gravitational-wave detection. Liuliang introduced to detect gravitational waves have a variety of means, using a Laser Interferometer, you need three satellites, space cold-Atom interferometers requires only two satellites, technical difficulty and cost is reduced.
Meanwhile, space cold atomic clock can measure gravitational red shift. According to general relativity, no unified concept of time, in different gravitational field of Mars, the Moon, time is not the same. "If there is a clock, there is a clock on the ground, then, you know how much time, and then use the time difference can be measured the gravitational redshift. "Liuliang said. In the near future, cold space the development of atomic clocks may give answers to many of the conjecture is clearly science fiction world. (End)
Responsible editor: Kang Yunkai
Article keywords:Temple on the second atomic clock
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Xinhua
3000万年误差1秒！揭秘
天宫二号空间冷原子钟|
天宫二号|原子钟_新闻资讯
新华社上海9月17日电（记者王琳琳）成功发射的天宫二号搭载了多种高精尖科学装备。其中，由中科院上海光机所研制的“定时神针”——空间冷原子钟，有望实现约3000万年误差1秒的超高精度，这将是国际上首台在轨运行并开展科学实验的空间冷原子钟，也是目前在空间运行的最高精度原子钟。
人类社会发展离不开对时间的精确测量。之前，在太空中运行的原子钟都是热原子钟，精度最高对应300万年误差1秒。此次，由天宫二号搭载的空间冷原子钟将激光冷却技术送入太空，在空间微重力环境下，进一步使时间精度提升10倍，意味着这台钟运行3000万年才会有1秒的误差！
如此精准的钟到底有什么作用呢？上海光机所中科院量子光学重点实验室主任刘亮介绍，在太空中，空间冷原子钟可以建立超高精度时间频率基准。有了这个基准，就可以把天上其他原子钟同步起来，让全球卫星导航系统具有更加精确和稳定的运行能力。
此外，冷原子技术的发展还将大幅提高许多实验的精度，让原来不可能进行的实验成为可能。例如，开展深空导航定位。刘亮说，如果我们在太阳系中不受引力影响的拉格朗日点各放置一台冷原子钟，人类就可以超越近地范围、在太阳系这个更大的范围内实现准确定位，开展大尺度时空研究，包括广义相对论在大尺度情况下是否成立等。
又如，空间冷原子干涉仪可以取代空间激光干涉仪，实现在轨引力波探测。刘亮介绍，探测引力波有多种手段，采用激光干涉仪探测，需要三颗卫星，空间冷原子干涉仪只需要两颗卫星，技术难度和成本都有所降低。
同时，空间冷原子钟还能测量引力红移。根据广义相对论，时间没有统一的概念，在火星、月球等不同的引力场里，时间都是不一样的。“如果天上有个原子钟，地面也有个原子钟，那么一比较，就知道时间相差多少，然后利用这个时间差就可以测量引力红移。”刘亮说。在不远的将来，空间冷原子钟的发展或许能让科幻世界的诸多猜想得到明确的解答。（完）
责任编辑：康云凯
文章关键词： 天宫二号 原子钟
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