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| Fantastic Four |
 Title text: One perk of being born at 0.88c is that your birthday is over two days long. |
Explanation
The comic is a pun on the Oberth effect, which causes orbital maneuvers to be more efficient when deep into a gravitational well. The movie referenced is The Fantastic Four: First Steps, released in 2025. The comic says that there is a boost because of the propulsion produced by the baby (a 'birth', rather than a 'berth').
This effect is probably zero, as the change in the centre of mass of the ship and crew would not constitute a form of effective reaction-based propulsion. [citation needed]
The title text states that being born at 88% the speed of light results in a birthday that's over two days long. This is due to time dilation, and from the perspective of Earth. At 0.88 c, the dilation factor γ is 2.1 . So one day is 2.1 days seen from Earth.
Transcript
- [Ponytail is facing Cueball with one of her hands out, facing up and towards Cueball.]
- Ponytail: In the new Fantastic Four movie, their ship doesn't have enough fuel to get home and Sue Storm goes into labor, so they slingshot around a neutron star and fire their engines at periapsis — as Sue has her baby — to get a boost.
- Cueball: Ah yes, the Obirth effect.
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