Once deployed, the robot is magnetized, so it can stick to the hull, then move around taking video of the ship.

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But nobody really knows how long disks stay magnetized.

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This toy consists of magnetized building blocks for boys.

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Our mission, as it's planned, is to fly over some of the oldest terrain on Mars, very highly magnetized crustal material that dates back to the beginning of Mars, 4.6 billion years ago.

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