"Go for TLI": How NASA put Astronauts on the Moon and Returned Them Safely to Earth

Register Here.

At 8:30 p.m. on December 21, 1968, Mission Control in Houston informed the Apollo 8 crew that they were “go for TLI,” Translunar Injection, the engine burn that would take the spacecraft on a trajectory to the moon. For the first time in history, humans left Earth orbit.

Instead of relying on raw processing speed, NASA used Isaac Newton’s laws of motion and universal gravitation alongside Johannes Kepler’s laws of planetary motion to map out cosmic highways, letting the universe's own gravity do the heavy lifting. While massive IBM mainframes on Earth and a global web of antenna stations tracked the spacecraft's every move, the Apollo Guidance Computer managed critical tasks on board. As the ultimate backup, astronauts used a space-age sextant to sight physical stars, ensuring they could navigate home even if they lost touch with Earth.

This lecture will debunk the myth that Apollo’s "minimal" computing power made the Moon landings impossible. We will explore how NASA engineers achieved the lunar landings through a combination of centuries-old math, cutting-edge engineering, and human eyesight.