Astronauts coming home from long stays on the International Space Station have, for years, described a strange perceptual aftertaste: a sense of watching their own lives from a half-step outside the frame. They sit at dinner with family and feel like a guest. They drive on a familiar street and feel like they’re piloting it. The room is loud and they are in it, but a part of them is hovering near the ceiling, taking notes.

There is still a lot that we don’t know. About everything. This phenomenon that astronauts report is really fascinating.

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