SpaceX launches hefty rocket with 24 satellites, experiments

SpaceX launched its heftiest rocket with 24 research satellites Tuesday, a middle-of-the-night rideshare featuring a deep space atomic clock, solar sail, a clean and green rocket fuel testbed, and even human ashes.

Five things to know about NASA's Deep Space Atomic Clock

NASA is sending a new technology to space on June 22 that will change the way we navigate our spacecraft—even how we send astronauts to Mars and beyond. Built by NASA's Jet Propulsion Laboratory in Pasadena, California, ...

Quantum computing boost from vapour stabilising technique

A technique to stabilise alkali metal vapour density using gold nanoparticles, so electrons can be accessed for applications including quantum computing, atom cooling and precision measurements, has been patented by scientists ...

Adding satnav to turn power grids into smart systems

An ESA-backed project is harnessing satnav to insert an intelligent sense of place and time to power grids, to provide early warning of potentially dangerous electricity network failures.

Atomic beams shoot straighter via cascading silicon peashooters

To a non-physicist, an "atomic beam collimator" may sound like a phaser firing mystical particles. That might not be the worst metaphor to introduce a technology that researchers have now miniaturized, making it more likely ...

New super-accurate optical atomic clocks pass critical test

Researchers have measured an optical clock's ticking with record-breaking accuracy while also showing the clock can be operated with unprecedented consistency. These achievements represent a significant step toward demonstrating ...

Testing the symmetry of space-time by means of atomic clocks

In his Special Theory of Relativity, Einstein formulated the hypothesis according to which the speed of light is always the same, no matter what the conditions are. It may, however, be possible that—according to theoretical ...

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Atomic clock

An atomic clock is a type of clock that uses an atomic resonance frequency standard as its timekeeping element. They are the most accurate time and frequency standards known, and are used as primary standards for international time distribution services, and to control the frequency of television broadcasts and GPS satellite signals.

Atomic clocks do not use radioactivity, but rather the precise microwave signal that electrons in atoms emit when they change energy levels. Early atomic clocks were masers with attached equipment. Currently the most accurate atomic clocks are based on absorption spectroscopy of cold atoms in atomic fountains such as the NIST-F1.

National standards agencies maintain an accuracy of 10-9 seconds per day (approximately 1 part in 1014), and a precision set by the radio transmitter pumping the maser. The clocks maintain a continuous and stable time scale, International Atomic Time (TAI). For civil time, another time scale is disseminated, Coordinated Universal Time (UTC). UTC is derived from TAI, but synchronized, by using leap seconds, to UT1, which is based on actual rotations of the earth with respect to the mean sun.

This text uses material from Wikipedia, licensed under CC BY-SA