Where did it acquire the energy needed to pop into a cloud the size of Jupiter? An asteroid impact? A satellite body ?
By an odd coincidence, I weighed in on one new energy storage mechanism that can lead to comet outbursts far from the warming sun in a scientific paper in Naturwissenschaften whose basics were reviewed in Adamant earlier this year.
This is not to imply we yet know what is happening to Comet Holmes which only takes seven years to complete an orbit , but that we have a lot to find out about energetic phenomena out in the Big Cold-at present, the surface temperature of comet Holmes is barely high enough to allow ice to sublimate.