Flamsteed AS Prof Allan Willis

[Pics Grey Lipley]

Flamsteed Astronomy Society

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Several more slides followed: a beautiful picture of Kepler Supernova 1604; Orion nebula M42; plus several Chandra X-ray images, finishing with an impressive image of The Whirlpool Galaxy M51. Massive ‘O’ stars have Main Sequence lifetimes of a few million years. (Our sun will have lasted for 10 billion years). Massive O stars are formed in the spiral arms of galaxies and in some galaxies (like M51) are found in Massive Super Star Clusters, where concentrations of hundreds of O stars have been discovered in regions only a few parsecs across. Galaxies like M82, called Starburst galaxies, contains thousands of O stars in their core, which are producing galactic winds and spewing processed material into the Inter-Galactic medium.

Allan then went on to talk about Gamma Ray Bursters which were discovered in 1963 by Vela satellites. A review in 1973 of Vela data indicates “…interesting signals that do not originate on the Earth, Sun, or Moon.” Recent work has shown that the Long Duration Gamma ray Bursts result from jets of gamma rays produced in the core-collapse supernova of Wolf-Rayet stars.

This led on to his penultimate slide which is worth reproducing here:-

Hot Massive Stars ( O and WR ) are first stars formed after Big Bang

Their strong UV radiation re-ionizes the Universe

Their nuclear burning produces the first generation of elements which enriches the Universe through winds and Super Nova

Enriched material produces new stars and Galaxy formation

The final slide of the evening was of Dr John Griffiths relaxing at his villa in Spain where he had just completed building a home observatory – something that had been an ambition of his for many years, and it is fitting that many of John’s friends, who are Flamsteed Members, are planning to visit the Observatory for a few days next year.

This first John Griffiths Memorial Lecture was a worthy tribute to a great man, a great astronomer, a great friend, and an inspirational teacher.