Adam Rutherford talks to astrophysicists about the astronomical discovery of the year, if not the last couple of decades: the collision of two neutron stars and the cosmic gold-forging aftermath. The discovery of this long-hypothesized event on 17th August came from the much awaited marriage of the capabilities of the gravitational wave detectors LIGO and Virgo with those of ground-based and space-based telescopes. Samaya Nissanke of Radboud University, Sheila Rowan of the University of Glasgow and Nial Tanvir of the University of Leicester take Inside Science through the story.

What made the infamous 1883 eruption of Krakatoa so devastating? Roland Pease meets the earth scientists trying to answer the question by recreating in the lab the conditions under the volcano prior to the eruption.

Following a temperature-related faux pas by Adam in the last episode, Michael de Podesta of the National Physical Laboratory explains the difference between Celsius and Centigrade.

Producer: Andrew Luck-Baker.