The first period-41 oscillator in Conway's Game of Life was just found by Nico Brown: https://conwaylife.com/forums/viewtopic.php?p=163972#p163972
With that, oscillators of every period are known: Conway's Game of Life is omniperiodic! This has been one of the major open problems in the study of Conway's Game of Life even since its invention over fifty years ago.
This comes just 7 days after the second-to-last period, period 19, was discovered.
@isaacg ahh I see, yea that's pretty sweet still!
@awodeyar No, it's mainly just cool in that it's the culmination of decades of searching, designing and theorizing CGoL patterns, it doesn't have any major implications or theoretical relevance.