In a programme exploring light, Anne McElvoy is joined by Ann Wroe - who has walked the South Downs for her latest book considering painters including Ravilious and Samuel Palmer. Prof. Lucie Green has written a journey to the centre of the sun. The fluorescent creations of Dan Flavin the post war American artist go on show at Birmingham's Ikon Gallery curated by director Jonathan Watkins. And in Blackpool - home of the Illuminations - the Grundy Art Gallery is adding to its collection of light works – curator Richard Parry explains. Dan Flavin: It is What It Is and It Ain't Nothing Else runs at the Ikon Gallery in Birmingham from 13th April to 26th June.Six Facets Of Light by Ann Wroe is out now. She is also the author of Pilate: The Biography of an Invented Man.15 Million Degrees - A Journey to the Centre of the Sun is written by Dr Lucie Green, solar physicist at the Mullard Space Science Laboratory at UCL.Producer: Torquil MacLeod