At least that's the vibe I got from the circumstances of the feat right here, which was requested here
The planet seems to be around 370 pixels, judging by the black areas in the blast where it isn't stretching weirdly, while a more middle ground piece is 286 pixels, a discrepancy of 0.77297297297
There is no stated size for this planet, so the diameter of earth is 12,742 KM, making the distance traveled by that one piece 9849.22162158 KM, 9849221.62158 meters
Let's assume a timeframe of, say, 5 seconds. The blast is still happening in this shot, I could maybe vouch for 1 second, but I'll use this lowball for now, making the speed 1969844.32432 meters per second
So, .5 times 5.972×10^24 times 1969844.32432^2 is...
1.1586536e+37 Joules, 2.76924855949 Ronnatons, Large Planet level
Eh, why not. Let's use 3 and 1 second as a high end, which would reach into Rel speed, so plugging 3283073.87386 and 9849221.62158 meters per second and the mass into here gets...
Mid End: 3.219E+37 Joules, 7.69359464627 Ronnatons, Large Planet level
High End: 2.899E+38 Joules, 69.2877629063 Ronnatons, Dwarf Star level