Keele planet discoveries on Horizon


Posted on 16 March 2015

BBC2's flagship science programme, Horizon, dedicated last week's episode to 'Secrets of the Solar System', explaining how the discovery and understanding of extra-solar planets had led directly to improvements in our understanding of our own Solar System.

Hellier_Cole 90x90 A major part of this picture has been developed through understanding 'hot Jupiters', a class of planets which is dominated by discoveries from Keele's WASP-South planet search, led by Professor Coel Hellier.  In particular the finding of hot Jupiters in retrograde orbits around their star was based on WASP-South planets, starting with WASP-17b.  The programme, typically watched by two million in the UK and re-broadcast worldwide, featured a 20-minute disucssion of hot Jupiter anchored around an observation of WASP-84b using the Telescopio Nazionale Galileo on La Palma.

WASP-84b is a WASP-South planet that was announced in a 2014 paper led by Keele postdoc David Anderson. The finding of an aligned orbit for this planet, annouced in a 2015 follow-up paper, also led by Anderson, is evidence that this particular planet has migrated inwards to its current orbit by interaction with the proto-planetary disk, and not by a close encounter with another large planet.  The programme showed how WASP discoveries are having a direct impact on our understanding of our Solar System, and thus the origin of our own Earth.