Organisers of Green Man Festival, held from 19-21 August in Glanusk Park near the Brecon Beacons, have added new acts to Einstein's Garden.
The area will host a mixture of workshops, installations and performances, including Answer Me This, With Love From Humans! and The Bright Club.
Mark Miodownik will present Does Size Matter?, with Praying Mantis Kung Fu and The Science and Fiction of Doctor Who set to join him.
Tom Wrigglesworth, Tony Law and Trevor Lock are the first of fifty comedians to join the billing, followed by Alistair Barrie, Gary Delaney and Mike Wozniak.
Helen Arney, Maeve Higgins, Mark Olver and Bec Hill also join the comedy line-up, with Tom Bell and Terry Saunders completing the new additions.
The new acts join Fleet Foxes, Explosions in the Sky and Iron and Wine on the billing for the three-day festival.
Adult weekend tickets are on sale now for £135, with a student concession available.