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What you will learn in The Apollo Program

1. Why go to the Moon
Filter the timeline to the Moon and read what was already taken. The Moon was chosen because it was the one destination nobody's existing hardware could reach — and the first Apollo crew died on the pad before any of it flew.
2. Getting there
A free return is a trajectory that comes home without firing anything. The bar under the scene is the measured set of injection speeds that do — about fifteen metres per second out of eleven thousand, and you can walk out of it with the slider.
3. The landing
Apollo 8 and Apollo 11 both launched on a free return and burned out of it, because a free return goes round the Moon and a landing has to stop at it. Then Eagle came down with the computer alarming and about twenty-five seconds of usable propellant left.
4. Apollo 13
The oxygen tank ruptured 320 000 kilometres out and the crew did not have to compute a way home, because they were already on one. The preset that shows you why is a corridor setting rather than a reconstruction, and the chapter's second step is about the difference.
5. After Apollo, and Artemis
Apollo 17 left the Moon in December 1972 and Artemis II flew round it in April 2026 — the first crewed lunar flight since Apollo 17 in 1972. Both are presets in the same widget, and the sentence that was true in between is the misconception this chapter exists for.

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1. Why go to the Moon
Filter the timeline to the Moon and read what was already taken. The Moon was chosen because it was the one destination nobody's existing hardware could reach — and the first Apollo crew died on the pad before any of it flew.
2. Getting there
A free return is a trajectory that comes home without firing anything. The bar under the scene is the measured set of injection speeds that do — about fifteen metres per second out of eleven thousand, and you can walk out of it with the slider.
3. The landing
Apollo 8 and Apollo 11 both launched on a free return and burned out of it, because a free return goes round the Moon and a landing has to stop at it. Then Eagle came down with the computer alarming and about twenty-five seconds of usable propellant left.
4. Apollo 13
The oxygen tank ruptured 320 000 kilometres out and the crew did not have to compute a way home, because they were already on one. The preset that shows you why is a corridor setting rather than a reconstruction, and the chapter's second step is about the difference.
5. After Apollo, and Artemis
Apollo 17 left the Moon in December 1972 and Artemis II flew round it in April 2026 — the first crewed lunar flight since Apollo 17 in 1972. Both are presets in the same widget, and the sentence that was true in between is the misconception this chapter exists for.