{
  "id": 1876616,
  "title": "Flying clocks in opposite directions around the world proved Einstein right",
  "url": "https://urgent.news/2026/08/19/flying-clocks-in-opposite-directions-around-the-world-proved-einstein",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-19T06:00:00.000Z",
  "source": {
    "name": "Big Think",
    "slug": "big-think",
    "url": "https://bigthink.com/starts-with-a-bang/flying-proved-einstein-right/"
  },
  "original_language": "en",
  "account": "In 1905, Einstein revolutionized our understanding of the Universe with his special theory of relativity. Prior to this, scientists described every point in the Universe using four coordinates - three for position in space, and one for time. However, Einstein introduced the idea that each observer's perspective on where and when events occur depends on their motion and location - both space and time are relative.\n\nEinstein suggested that two clocks, one at the equator moving around the Earth at around 1670 km/hr, and one at the poles which is at rest with respect to the Earth's rotation, could be used to test this theory. To everyone's surprise, both clocks ran at the same rate relative to each other. This was due to the constancy of the speed of light, a key principle of special relativity.\n\nEinstein's theory also predicted that the passage of time would be affected by gravity. Closer to a large gravitational mass, time slows down, a phenomenon known as gravitational time dilation. The Earth bulges at the equator and is compressed at the poles due to its rotation and gravitational forces. As a result, the Earth's gravitational pull at the poles is slightly stronger than at the equator. Interestingly, the time dilation effects due to the Earth's rotation get cancelled out by the gravitational time dilation at different locations on Earth.\n\nTo fully understand the rate of time for each observer, we must consider both special and general relativity. In general relativity, the presence of mass causes spacetime to curve, and this curvature affects the passage of time. Even at infinite distances, the curvature of spacetime remains non-zero.",
  "summary": "In 1905, our conception of the Universe changed forever when Einstein put forth his special theory of relativity. Prior to Einstein, scientists were able to describe every “point” in the Universe with the use of just four coordinates: three to designate position for each of the three spatial dimensions, plus a time to indicate at which moment any particular event occurred. All of this changed…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}