The Sky at Night Catch up, Greenwich: A Journey Through Space and Time on BBC 4

The Sky at Night

Greenwich: A Journey Through Space and Time

To celebrate the 350th anniversary of the Royal Observatory, the team recreate history. \n\nIn the times of the early Astronomers Royal, scientists would gather at spectacular dinner parties at Flamsteed House in Greenwich to share ideas and discuss the universe. \n\nIn 2025, 350 years on from the first ground stones being laid, we come together once again to discover how the work at the Royal Observatory defined the prime meridian, fundamentally changing our world, and blasting technology and communications forward into the global economy we know today.\n\nSince then, world time zero has run through Greenwich, but our understanding of time has grown. It is not constant, but is in fact relative to each and every one of us. Our experience of time changes depending on where and what we are in the universe - with surprising effects that scientists are still uncovering today. \n\nWe find out if the second will need to be redefined in 2030, explore the implications of time being stretched and squeezed by gravity, and visit the most extreme regions of space that bend time back on itself - breaking physics as we know it. \n\nJoining presenters Maggie Aderin-Pocock and Pete Lawrence at the dinner table is a glittering line-up of science communicators. \n\nDr Rebekah Higgitt, a historian of science and a past curator at the Royal Observatory, gives us a deep insight into the wealth of characters whose work defined modern science and technology here.\n\nWe explore the discovery and nature of black holes with astrophysicist Dr Becky Smethurst from the University of Oxford. \n\nProfessor Jim Al-Khalili provides a quantum approach to time, probing why it is that we exist in a universe where time seems destined to flow in only one direction - forwards.\n\nMeanwhile, Chris Lintott is in the field, meeting Dr Louise Devoy in the coveted conservation stores of the Royal Observatory, the high-tech Prince Philip Maritime Collections Centre, to look at a very special object from 1919 that proved Einstein right about a fundamental new property of our universe. \n\nChris interviews Professor Claudia de Rham about the most extreme regions of the cosmos - those that rip holes in space-time, where Einstein’s theory is destined to fail - sparking new theories of quantum gravity dating back to the birth of the universe itself. Can we say when the cosmological 'clock' started ticking?\n\nJoin the team on a journey through space and time.

Source: BBC 4

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