what did astronaut lovell radio when the engines of apollo 8 worked so that the spacecraft could leave lunar orbit?

Jim Lovell radioed the playful confirmation: “Roger, please be informed there is a Santa Claus.”

Quick Scoop

When Apollo 8 fired its engine to leave lunar orbit on Christmas 1968, mission control had to wait in silence while the spacecraft passed behind the Moon, unable to communicate. As the signal returned and engineers anxiously checked if the burn had worked, Lovell calmly and humorously sent his now-famous message: “Roger, please be informed there is a Santa Claus.”

This line signaled that the critical Trans-Earth Injection burn was successful and that Apollo 8 was safely on its way home. Because it happened on Christmas and wrapped good news inside a light-hearted phrase, it has since become one of the most memorable radio calls of the early space age.

TL;DR: When Apollo 8’s engine burn to leave lunar orbit succeeded, Lovell radioed, “Roger, please be informed there is a Santa Claus,” confirming the spacecraft was heading safely back to Earth.

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