Figure eight on pentadecathlon is a period-120 oscillator composed of a figure eight and pentadecathlon. Although it is composed of two oscillators of smaller periods (8 and 15 respectively), it is considered non-trivial, because it contains one cell that is alive in generation 95 and dead in the other 119 phases of the oscillator. In terms of its 24 cells, it is the smallest known non-trivial period-120 oscillator.
There is a variant of this oscillator with a slightly larger bounding box, and two other 26-cell variants which have 3 cells with period 120.
It first appeared in an asymmetric soup on March 3, 2019, in a haul submitted to Catagolue by benetnasch85. This makes it the highest period oscillator to have occurred naturally.
Generation 95 reveals the single cell with period 120 (in green)
The 26-cell variant, showing 2 of the 3 cells with period 120 (in green)Download RLE: click here
Generation 119 of the 26-cell variant, showing the other cell with period 120 (in green)