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Freeman Dyson - Claire Max and adaptive optics (127/157)

4,868 views · Published 2 September 2016 · 2:21 · Indexed 6 November 2026

Channel: Web of Stories - Life Stories of Remarkable People · 2016 · Science & Technology

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To listen to more of Freeman Dyson’s stories, go to the playlist: https://www.youtube.com/playlist?list=PLVV0r6CmEsFzDA6mtmKQEgWfcIu49J4nN

Freeman Dyson (1923-2020), who was born in England, moved to Cornell University after graduating from Cambridge University with a BA in Mathematics. He subsequently became a professor and worked on nuclear reactors, solid state physics, ferromagnetism, astrophysics and biology. He published several books and, among other honours, was awarded the Heineman Prize and the Royal Society's Hughes Medal. [Listener: Sam Schweber; date recorded: 1998]

TRANSCRIPT: And so that was the situation for 10 years after that. And... during that time Claire Max got involved. She was by that time at JASON, and she pushed in two directions. First of all was to get the thing declassified. She works at Livermore and she had very good connections with the classified work and with the people who were running the programme in the Airforce, and she persuaded, after a lot of very careful diplomacy, she persuaded the Airforce that they were not going anywhere unless they had the thing out in the open, that they absolutely needed to have people on the outside look at it, and she finally persuaded the Airforce to declassify the whole thing, which they have done. So for the last five years it's again been out in the open and progress from that time on has been great. So Claire herself is now leading a project to use adaptive optics for astronomy at the Lick Observatory and the Keck telescopes, and she has developed another invention which is the laser guided adaptive optics, which is a very beautiful idea. You... you have a rather powerful yellow laser, of the order of a kW, which points a very narrow beam up into the sky and it illuminates the sodium layer, which is a layer of sodium atoms about 90km above the ground, which is a fairly narrow layer, and these sodium atoms fluoresce vigorously when the laser light illuminates them. So you get a point source in the sky which is as good as a star from point of view of focusing, so you make your own artificial star. So then you can actually do adaptive optics very nicely in any direction you want and just point the laser in the direction you want to observe. The sodium light being one single frequency doesn't interfere with the astronomical observation. So this is the new technique and it's now no longer in any way hindered by the military and it's becoming a very... a very effective way of doing astronomy. And Claire has been just wonderful in getting this actually all organised and making it happen.

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