{"id":143671,"date":"2025-06-01T05:44:32","date_gmt":"2025-06-01T05:44:32","guid":{"rendered":"https:\/\/teknomers.com\/en\/einstein-never-anticipated-this-an-orbiting-atomic-clock-challenges-relativity-from-space\/"},"modified":"2025-06-01T05:44:34","modified_gmt":"2025-06-01T05:44:34","slug":"einstein-never-anticipated-this-an-orbiting-atomic-clock-challenges-relativity-from-space","status":"publish","type":"post","link":"https:\/\/teknomers.com\/en\/einstein-never-anticipated-this-an-orbiting-atomic-clock-challenges-relativity-from-space\/","title":{"rendered":"Einstein never anticipated this: an orbiting atomic clock challenges relativity from space."},"content":{"rendered":"\n<div>\n<figure class=\"wp-block-table\">\n<table>\n<tbody>\n<tr>\n<td><strong>IN BRIEF<\/strong><\/td>\n<\/tr>\n<tr>\n<td>\n<ul>\n<li>\ud83d\ude80 The \u00a0PHARAO mission\u00a0 aims to test \u00a0general relativity\u00a0 by measuring the flow of time from the ISS.<\/li>\n<li>PHARAO utilizes an \u00a0atomic clock\u00a0 of exceptional precision, developed by CNES.<\/li>\n<li>This experiment could reconcile \u00a0general relativity\u00a0 with \u00a0quantum mechanics\u00a0.<\/li>\n<li>Results might improve the \u00a0accuracy\u00a0 of satellite positioning systems.<\/li>\n<\/ul>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n<p>The upcoming \u00a0PHARAO space mission\u00a0, scheduled for April 21, 2025, marks a significant milestone in the scientific exploration of space. At the heart of this mission lies an \u00a0atomic clock\u00a0 of unparalleled precision, set to measure the passage of time from the \u00a0International Space Station (ISS)\u00a0. This groundbreaking experiment is aimed at testing one of the most fascinating predictions of \u00a0Einstein&#8217;s general relativity\u00a0. With this mission, we hope to gather data that may bring us closer to reconciling general relativity with \u00a0quantum mechanics\u00a0, two foundational yet incompatible theories in their current states. PHARAO could open new avenues in our understanding of the Universe.<\/p>\n<h2>An Atomic Clock in Space to Verify General Relativity<\/h2>\n<p>The \u00a0Atomic Clock Ensemble in Space (ACES)\u00a0 mission, set to launch towards the ISS, promises to revolutionize our comprehension of general relativity. Under the auspices of the \u00a0European Space Agency (ESA)\u00a0, this mission will carry the \u00a0PHARAO atomic clock\u00a0, developed by \u00a0CNES\u00a0. This clock aims to measure a unique prediction of general relativity: the effect of an object&#8217;s mass on the flow of time around it. The principle is simple: <i>the greater the mass of an object, the slower time flows in its vicinity<\/i>.<\/p>\n<p>At the altitude of the ISS, an astronaut will age slightly faster than his twin remaining on Earth, although this effect is minimal. PHARAO aims to measure this phenomenon with unprecedented accuracy, deviating no more than two-tenths of a second since the disappearance of the dinosaurs. To achieve this goal, the clock must be compared precisely to clocks remaining on Earth via sophisticated microwave and laser links.<\/p>\n<h2>An Atomic Clock on the International Space Station<\/h2>\n<p>Installed on the \u00a0European Columbus module\u00a0 of the ISS, PHARAO benefits from the station&#8217;s resources while seeking to overcome the inherent challenges of its environment. The moderate radiation conditions and the proven communication infrastructures of the ISS provide an ideal setting for this experiment. However, the relatively low altitude of the ISS limits the effect of \u00a0general relativity\u00a0 that PHARAO can observe, compared to a geostationary orbit where this effect would be more pronounced.<\/p>\n<p><picture><source data-lazy- type=\"image\/webp\"><img decoding=\"async\" src=\"https:\/\/teknomers.com\/en\/wp-content\/uploads\/2025\/06\/une-decouverte-renversante-70-ans-apres-einstein-cette-horloge-atomique-sur-liss-defie-les-lois-de-l.jpeg\" alt=\"\" class=\"webpexpress-processed\"\/><\/source><\/picture><\/p>\n<p>Despite these challenges, PHARAO has the potential to fulfill its objectives before the decommissioning of the ISS, scheduled for 2030. <i>The results obtained could not only deepen our understanding of relativistic effects but also enhance the accuracy of satellite positioning systems<\/i>.<\/p>\n<h2>Atomic Clocks Becoming More Precise<\/h2>\n<p>Since their inception in the 1950s, \u00a0atomic clocks\u00a0 have improved at an impressive rate, paralleling the evolution of electronic systems. Based on the unique frequencies of atoms, these clocks have become time-measurement instruments of unmatched precision. \u00a0Radio, optical\u00a0, and potentially \u00a0nuclear atomic clocks\u00a0 represent significant advancements in this field.<\/p>\n<p>PHARAO relies on a major advancement: the use of \u00a0laser-cooled atoms\u00a0, a technique that earned physicist \u00a0Claude Cohen-Tannoudji\u00a0 a Nobel Prize. <strong>In the microgravity environment of the ISS, these cooled atoms allow for extremely precise time measurement<\/strong>. The ultra-high vacuum required to maintain these conditions is an engineering feat, eliminating any unwanted interactions with other atoms.<\/p>\n<h2>The Potential Impact on Chronometric Geodesy<\/h2>\n<p>The precision of PHARAO enables the detection of minute variations in gravitational potential, equivalent to altitude changes of one meter. Terrestrial \u00a0optical clocks\u00a0, even more precise, can detect variations of one centimeter. These capabilities open new avenues in \u00a0chronometric geodesy\u00a0, allowing for the study of changes in terrestrial masses, from groundwater variations to atmospheric movements.<\/p>\n<p><i>With even more advanced clocks connected to a reference in space, we could one day measure terrestrial phenomena with unparalleled precision<\/i>. This raises the question: what other unexpected applications could this technology offer in the future?<\/p>\n<p>This article has been enriched with the help of artificial intelligence.<\/p>\n<p id=\"rating\"><span>Did you like it? <span class=\"star full-star\"\/><span class=\"star full-star\"\/><span class=\"star full-star\"\/><span class=\"star full-star\"\/><span class=\"star empty-star\"\/><\/span><span>4.3\/5 (20)<\/span><\/p>\n<\/div>\n<p><br \/>\n<br \/><a href=\"https:\/\/teknomers.com\/category\/general\/\" rel=\"dofollow\">General News &#8211; 2<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>IN BRIEF \ud83d\ude80 The \u00a0PHARAO mission\u00a0 aims to test \u00a0general relativity\u00a0 by measuring the flow of time from the ISS. PHARAO utilizes an \u00a0atomic clock\u00a0 of exceptional precision, developed by CNES. This experiment could reconcile \u00a0general relativity\u00a0 with \u00a0quantum mechanics\u00a0. Results might improve the \u00a0accuracy\u00a0 of satellite positioning systems. The upcoming \u00a0PHARAO space mission\u00a0, scheduled [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":143672,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[36399],"tags":[],"class_list":["post-143671","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-technology"],"_links":{"self":[{"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/posts\/143671","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/comments?post=143671"}],"version-history":[{"count":0,"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/posts\/143671\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/media\/143672"}],"wp:attachment":[{"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/media?parent=143671"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/categories?post=143671"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/teknomers.com\/en\/wp-json\/wp\/v2\/tags?post=143671"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}