Latest news with #AtomicClockEnsembleinSpace
Forbes
22-04-2025
- Science
- Forbes
SpaceX Launches Atomic Clocks With Lasers To Test Einstein Theory
Two cutting-edge atomic clocks — the most accurate ever created — have launched on a SpaceX rocket and are on their way to the International Space Station. In the coming months, they will use lasers to synchronize global clocks using global navigation satellite networks. Artist's impression showing the European space laboratory Columbus that is part of the International ... More Space Station with the Atomic Clock Ensemble in Space containing the PHARAO and Space H-Maser atomic clocks. The Atomic Clock Ensemble in Space will 'redefine how we measure time,' according to the European Space Agency, which developed it. It will transmit the most accurate time signal ever from space and create an 'internet of clocks,' comparing them to measure the flow of time. That will help scientists study Earth's gravity. According to ESA, an atomic clock measures time by observing an atom's transition from an excited state to a ground state with a fixed frequency. The ACES clocks — PHARAO and SHM — will be used to test fundamental physics from orbit, including Albert Einstein's theory of general relativity and the search for dark matter, said ESA. It will do that by defining how time and space are related. Built by the French space agency CNES and Safran Timing Technologies in Switzerland, the ACES clocks are so precise that they would lose just one second in 300 million years. However, they will not stay in orbit for long. With the ISS due to be deorbited in the late 2020s, they are destined to burn up in Earth's atmosphere alongside the rest of the station. The ACES clocks have a time transfer system built by German company TimeTech that will use microwave and laser links to synchronize time between space and Earth. The mission will also test how to synchronize clocks worldwide using GPS satellites. 'We are placing the most precise timepiece ever sent to orbit aboard the International Space Station — opening new frontiers in fundamental physics, time transfer, and global synchronization,' said Daniel Neuenschwander, Director of Human & Robotic Exploration at ESA. He called it a 'major milestone for European science and international cooperation in space.' The ACES clocks launched atop a SpaceX Falcon 9 rocket from NASA's Kennedy Space Center in Florida at 4:15 a.m. EDT on Monday, April 21. It was part of NASA's SpaceX 32nd Commercial Resupply Services mission to fly scientific experiments and 6,700 pounds of supplies to the International Space Station in a Dragon space capsule. It will dock at the ISS around 8:20 a.m. Tuesday, April 22. The ACES clocks are scheduled to be installed outside ESA's Columbus module on Friday, April 25, facing Earth, where they will begin at least 10 measurement sessions, each lasting 25 days. The 'bowling ball on a sheet' analogy is a popular way to visualize gravity in general relativity. Albert Einstein's general theory of relativity describes how the cosmos works. The universe is 4D — it has three dimensions in space and one in time. Relativity is about what happens when you introduce mass into the 4D universe. The theory is encapsulated by the bowling ball (mass) on the trampoline (space-time), with the former stretching the latter. Mass curves space-time. Space-time controls how mass moves. If space-time is curved, everything with mass moves in a curved line. Gravity is a symptom of curved space-time; the sun changes the geometry of space-time around it, and light beams curve as they pass through curved space-time. According to NASA, ACES will measure Einstein's 'gravitational redshift,' an effect of Einstein's theory whereby light shifts to redder colors because of gravity. Gravitational redshifts impact the accuracy of GPS positioning. This theory was first published by Einstein in 1915, during the First World War, but remained unproven until photographs were taken during a total solar eclipse on May 19, 1919, that demonstrated light deflection. The images showed that the presence of the sun's mass in a dark sky shifted where stars appeared to be because the sun curved space-time. The light from stars around it traveled in a curve through it and appeared in a slightly different place than where they normally would.
India Today
21-04-2025
- Science
- India Today
Nasa launches atomic clocks to space to prove Einstein's theory about time
Nasa, in collaboration with the European Space Agency (ESA), has launched two state-of-the-art atomic clocks to the International Space Station (ISS) as part of the Atomic Clock Ensemble in Space (ACES) atomic clocks were launched aboard the SpaceX Dragon spacecraft to the ISS, along with food, resupplies and new experiments for the atomic clock payload to be installed on the ISS's Columbus module, aims to push the boundaries of precision timekeeping and fundamental physics IS ATOMIC CLOCK? An atomic clock is the most accurate type of clock in the world — it keeps time using the vibrations of atoms, usually cesium-133 or rubidium-87, as its timekeeping payload launched on Monday features two complementary atomic clocks: PHARAO, a laser-cooled cesium clock developed by the French space agency, and the Space Hydrogen Maser (SHM) from cools cesium atoms to near absolute zero in microgravity, allowing ultra-precise measurements, while SHM provides exceptional short-term stability. Together, they achieve a timing accuracy so precise that they would lose only one second every 300 million years. WHAT WILL THE ATOMIC CLOCKS DO IN SPACE?One of ACES's primary scientific goals is to test Einstein's theory of general relativity by measuring gravitational time dilation with unprecedented to Einstein, time passes differently depending on gravitational strength — clocks closer to Earth's surface tick slower than those in orbit. advertisementACES will compare its onboard clocks with highly accurate ground-based atomic clocks worldwide, searching for tiny deviations that could reveal new physics or constrain dark matter fundamental physics, ACES is set to revolutionize global time synchronization, enabling clock comparisons at resolutions that can detect geopotential height differences on Earth's surface with 10-centimeter capability has practical applications in relativistic geodesy, improving GPS accuracy, satellite navigation, and mission also aims to enhance the long-term stability of International Atomic Time (TAI) and demonstrate the transmission of ultra-stable time signals to Earth with uncertainties as low as 100 aboard Nasa's SpaceX CRS-32 resupply mission, the atomic clocks will operate for at least 30 months.
