Podcaster: Host : Fraser Cain; Guest: Dr. Victor Gysemberg ,Dr. Nick Castle, Dr. Paul Byrne, Beth Johnson

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Title: Hipparchus’ Lost Star Catalog with Dr. Victor Gysemberg

Link: Cosmoquest:


Today’s story:

  • Artemis 1 goodness!
  • Webb seeing so much exoplanet atmosphere.
  • A partial solar eclipse on Mars.
  • A precise asteroid impact prediction.
  • Mars rover update!

Host: Fraser Cain ( @fcain )

Special Guest: Greek astronomer Hipparchus, who lived in the second century BCE, is considered to be the greatest astronomical observer of his time. Among his achievements are the development of trigonometry, the ability to predict solar eclipses, discovering and measuring the precession of the equinoxes, and, in approximately 135 BCE, the compilation of the first comprehensive star catalogue in the western world. Since that time, scientists have spent centuries searching for Hipparchus’ Star Catalogue, but it disappeared and has never been found.

Or has it?

In 2017, researchers used multispectral imaging and computer algorithms to examine an ancient manuscript that had been discovered in a Greek Orthodox monastery in Egypt in 2012. The resulting images not only uncovered astronomy-related writings (e.g., Eratosthenes’ star-origin myths [] and the third-century poem Phaenomena [] about the constellations,) but also hidden in the manuscript were star coordinates. Could this manuscript include part of Hipparchus’ star catalogue?

Tonight we are airing Fraser’s prerecorded interview with Dr. Victor Gysembergh, research professor at the French National Scientific Research Centre. Victor is one of the two experts who examined the manuscript images – tune in to hear all about his conclusions.

Victor Gysembergh is a CNRS research professor at the Centre Léon Robin (Sorbonne Université). He is currently working on an edition of the fragments of Eudoxus of Cnidus, as well as on editions of Claudius Ptolemy’s treatise On the Analemma and his recently discovered treatise on the Meteoroscope.

You can read all about this exciting discovery here:

You can also read the resulting paper about this find here:

You can learn more about Hipparchus here: 

Regular Guests:

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365 Days of Astronomy

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