In this episode, Shashank, Cole and Cormac take a look at the periodic side of time-domain astronomy through the famed, fabled Fourier transform. Cole entreats us to the time lags in blazars and Cormac gives us a weather update on a brown dwarf. Along the way, we discuss some of the instruments, challenges and patterns in periodicity.

In this episode, we take a break from our usual astronomical antics to reflect on sustainability in the cosmos. Cormac, Cole and Shashank explore how the Universe manages to recycle material across all scales, from pepping up prostrated pulsars to cleaning up our orbital backyard. We conclude with a discussion of how analogies are (sometimes over)used in astronomy, and ponder when exactly a supernova remnant begins.