Rodent Wars Forum

We don't have asteroids in RW, but I'll look at this anyway. I will assume that the asteroid is 10 feet in diameter and is made of nickel-iron. Iron takes 1.28 MJ/kg to melt. The asteroid weighs about 116688.49 kg. And the debris is hurled away at roughly 10 m/s. So the energy to just melt it is ~149361 MJ, and the energy to hurl it is 5.8344 MJ.

So the two Photon torpedoes are dealing a total of approximately 149367 MJ (minimum). That's 74683.5 MJ each, or ~17.85 tons of TNT. [1]
Confidence in figure: 8/10 if we ignore scaling


[1]: https://www.justintools.com/unit-conversion/energy.php?k1=megajoules&k2=tons-of-TNT