: One of the most essential technical additions was the Patched Conics trajectory system . This allowed players to see their projected orbit as they entered and left the gravitational influence (SOI) of different planets or moons, making precise interplanetary maneuvers possible. Legally Downloading KSP
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Revisiting History: The Legacy of Kerbal Space Program 0.15 Kerbal Space Program (KSP) : One of the most essential technical additions