Stephen Sackur speaks to a scientist of rare distinction. Jocelyn Bell Burnell was a key member of the team which discovered pulsars and neutron stars in the late 1960s. She became one of the world's most renowned astrophysicists - remarkable not just for the originality of her research, but also for her gender. Throughout her career she has blazed a trail for women in a predominantly male world. Why are there so few women at science's top table?br br Broadcastbr 23rd May 2012br 4.30am - 5.