Guildford Astronomical Society

Prof David Waltham

Prof David WalthamProf David Waltham

A list of talks to GAS by Prof David Waltham is shown below.

DateTalk at GAS meeting
4 May 2017Is there Life on Proxima b?

NB: This is a change to the previously advertised talk.

Last year was remarkable in many ways but two events, unnoticed by many, may prove more significant in the long term than Brexit, Donald Trump or even the Brangelina break-up. In April of 2016, the world’s most famous living scientist (Stephen Hawking), and two of its richest men (Yuri Milner and Mark Zuckerburg) held a press-conference to announce a plan to send space-probes to our nearest star system, Alpha Centauri, within a few decades. Then, in August, the world’s most prestigious scientific journal published research showing that Proxima Centauri (the nearest member of the Alpha Centauri system) has a habitable planet—a world called Proxima b. Together these announcements imply that we could send a spaceship to a potentially inhabited planet orbiting another star, within the lifetime of most people alive today!

In this talk I will investigate how likely it is that Proxima b is not just habitable but actually inhabited (whether by green slime or little green men). I’ll do this by taking a “Copernican perspective” (i.e. I will assume that Earth is a typical inhabited planet) and explain why this strongly implies that worlds, such as Proxima b, that orbit red dwarfs are probably uninhabited. However, the only way to be sure is to take a good look and so I’ll also talk about how we can do that from a distance already and how we might be able to do it close-up, with a space-probe, as early as the 2060s.

5 Apr 2018Lucky Planet

Science tells us that life elsewhere in the Universe is increasingly likely to be discovered. But in fact the Earth may be a very unusual planet – perhaps the only one like it in the entire visible Universe. In his talk on the "Lucky Planet”, Professor Waltham asks why, and comes up with some surprising and unconventional answers.