R = (h/2) + c^2/(8h)
= (118/2) + 1297^2/(8 X 118)
= 2476.00693 X 2
= 4952.01386 pixels
D = 4952.01386 X 2
= 9904.02772 pixels
The diameter of the Earth is 12756.2km.
9904.02772 pixels = 12756.2km
1 pixel = 12756.2km/9904.02772 = 1.28798105km
1.28798105km X 735 = 946.666072km
946.666072km/2 = 473.333036km
Using the StarDestroyer.Net nuke calculator (for "Air blast radius (widespread destruction)") and we get 319400 megatons, or 319.4 gigatons.
Final Results
Alternate Gurren Lagann & Enki clash = 319.4 gigatons
