And one way you can create gravity is to spin things.

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The saucer section would be a 0.3-mile-diameter (536-meter-diameter) rotating, magnetically suspended gravity wheel that would create 1G of gravity.

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The technique uses distant light amplified by the gravity of a massive star or planet to create an astronomical magnifying lens.

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If local gravity differences are not pulling water about to create these features, then other factors such as currents, winds and tides must be responsible.

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And so you can artificially create that acceleration that makes you feel like you're in gravity just by rotating something like a centrifuge.

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Scientists such as Sir Isaac Newton considered the quest to create the stuff in a laboratory to be much more important than figuring out gravity and other principles that underpin our modern-day understanding of physics.

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