Jupiter gives us a taste of Armageddon

Last year, in July, something smacked Jupiter. Hard. It was discovered when an amateur astronomer found a black spot marring Jupiter's cloud tops. Followup observations saw the spot glowing in the infrared, meaning it was hot, and therefore was not just a storm (which are common). For real and for sure, something impacted Jupiter and exploded - and I mean exploded, releasing the equivalent of hundreds of thousands of nuclear weapons. But what was it?