52513M is a methuselah with a lifespan of 52513 generations, discovered by Dylan Chen on January 16, 2021, using apgsearch. A one-generation predecessor to it was found by Rocknlol in October of that year. Each of these were formerly the longest-lasting known non-infinitely-growing[note 1] methuselahs within a 16×16 square, until the discovery of 71093M. 52513M remains the longest-lasting methuselah found via soup search, and was found just a week after the previous record-holder, 50093M. On January 17, Adam P. Goucher found a 27-cell variant lasting 52444 generations. Other variants have been found by MathAndCode and Tanner Jacobi, including one with only 25 cells, which is shown below.
The stable pattern that results from 52513M (excluding 92 escaping gliders) has 4594 cells and consists of 380 blinkers (including 40 traffic lights), 342 blocks, 193 beehives (including eight honey farms), 50 loaves, 46 boats, 19 tubs, 18 ships, nine ponds, five toads, two barges, two separate half-bakeries, two long boats, and one beacon.
The methuselah is very directional; the ash is elongated and centered well northwest of the starting location.