Society Zoom Meeting – Lagrangian Points – Dr. Roger Wood
Following the spectacular success of Newton’s inverse square law of gravitation applied to planetary orbits, mathematicians spent much of the next 200 years elaborating the theory. In particular they made many unsuccessful attempts to derive equations which would describe the motions of three masses moving under their mutual gravitation alone – the so called “three body problem”. In the 18th century Euler and Lagrange found special case solutions, points in the orbital plane of each planet where a third smaller mass maintains a constant position with respect to the planet as it orbits the Sun – now generally known as Lagrangian points. In the space age Lagrangian points have received renewed interest as ideal locations for astronomical satellites and as energy efficient transit points for spacecraft. The astrometric satellite Gaia is currently orbiting the Sun-Earth Lagrangian point L2 and will be joined by the James Webb Space Telescope, successor to the Hubble Space telescope, when it is launched later this year. Mention will also be made of the Lagrangian points associated with other solar system planets.
I joined the RGO in 1964 after a physics degree at Exeter and, apart from a 3-year secondment to the Radcliffe Observatory in Pretoria, was based at Herstmonceux for the next 39 years. Early days were spent acquiring programming skills while working for theorist Donald Lynden-Bell on the thermodynamics of self-gravitating gas spheres. Then in South Africa I studied Milky Way rotation, work submitted to the University of Sussex for a PhD on return to the UK. There followed a 2-year spell as Public Information Officer before I became deeply involved with the efforts to set up the new observatory on La Palma – first as liaison with UK universities and subsequently writing control software (still in use now, 30+ years later!) for the Isaac Newton and William Herschel Telescopes. When the RGO moved to Cambridge in 1990 I took a sideways move to run (latterly jointly with Graham Appleby) the Satellite Laser Ranging station which remained at Herstmonceux and which continues to provide first class data to the global geodetic community to this day.
Due to the current Covid Rules we will, until further notice, host the Monthly Society Meeting via Zoom.
Details for the meeting will not be published on the Web but will be published in Orbit and/or sent via a member email. The Meeting ID and Password will change each month to keep it more secure. The meeting Waiting Room will be open from about 7:15 to allow members to join before 7:30. Please ensure you have your full name set up in Zoom, so we know who you are. The meeting will be recorded so that Phillip can produce his write-up, and the Zoom Host may Mute you to reduce feedback and allow the speaker to be heard. Questions can be asked via the text Chat function, or verbally if Unmuted or by pressing the spacebar.