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China's Atomic Clock in Space Will Stay Accurate For a Billion Years (rt.com)

Posted by msmash on from the when-every-second-counts dept.

The space laboratory that China launched earlier this week has an atomic clock in it which is more accurate than the best timepiece operated by America's National Institute of Standards and Technology, according to Chinese engineers. The atomic called, dubbed CACS or Cold Atomic Clock in Space, will slow down by only one second in a billion years. In comparison, the NIST's F2 atomic clock, which serves as the United States' primary time and frequency standard, loses a second every 300 million years. From an RT report:"It is the world's first cold atomic clock to operate in space... it will have military and civilian applications," said Professor Xu Zhen from the Shanghai Institute of Optics and Fine Mechanics, who was involved in the CACS project. An atomic clock uses vibrations of atoms to measure time, which are very consistent as long as the atoms are held at constant temperature. In fact, since 1967 the definition of second has been "9,192,631,770 vibrations of a cesium-133 atom." In a cold atomic clock, the atoms are cooled down with a laser to decrease the effect of atom movement on the measurements. CACS goes even further and eliminates the pull of Earth's gravity by being based in orbit.

6 of 111 comments (clear)

  1. Durability by ELCouz · · Score: 4, Insightful

    Well the atomic clock won't last that long see that second offset!

    1. Re:Durability by flopsquad · · Score: 3, Insightful

      "Cool clock, I hear it's accurate for a billion years!"
      "Yeah. But I keep it in this chaotic field of hypervelocity space debris where millions of tiny bits of junk are whizzing around, constantly threatening to punch a big hole in my clock."
      "So... you don't think it's going to last a billion years?"
      "I'm not optimistic."

      --
      Nothing posted to /. has ever been legal advice, including this.
  2. they could have used a grandfather clock by Anonymous Coward · · Score: 2, Insightful

    Because the satellite will come down in 10 years, maybe 20 anyhow.

  3. Fail High School Physics Artlcie! by CajunArson · · Score: 5, Insightful

    CACS goes even further and eliminates the pull of Earth's gravity by being based in orbit.

    Yeah, spot the glaring contradiction in that sentence. Hint: you can be free of the pull of Earth's gravity, or you can be in orbit around Earth... but not both!

    --
    AntiFA: An abbreviation for Anti First Amendment.
  4. jingoism by unixisc · · Score: 3, Insightful

    You mean that they haven't already, w/ those South China Sea islands, and all that?

  5. Re: ...and Accuracy by peragrin · · Score: 3, Insightful

    There is a much simpler reason why it won't last as long. Material degradation. Show me a system let alone a complex one like a satellite that doesn't lose bits of itself over time. Space radiation will slowly alter the chemical structure of the house, power supply, etc until it is non functioning and that will happen in just a thousand years or so

    --
    i thought once I was found, but it was only a dream.