Use arrow keys for movement, space to jettison booster. Using the small ship saves fuel, but it's slower. If you run out of fuel, you'll still fly. This way you can't be softlocked. Slowest possible time is ~170s.
Credit to Kerbal Space Program for inventing the Mun and Kerbin. Credit to Isaac Newton for the invention of gravity in 1666. <Update Log> May 4 2026-Added better variables (Credit to B-Reyn428) May 3 2026-Fixed a bug where you could have negative fuel, and the flame would still appear when you ran out.