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Space debris (also known as "orbital debris", "space junk", or "space waste") is the collection of defunct objects in orbit around Earth and includes everything from spent rocket stages, old satellite…
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Questions regarding the process of accurately finding your location, and getting to another place by planning and following a map.
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about the lack of evidence for alien life, despite the growing evidence that suitable planets are reasonably plentiful.
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Questions about Europa, a moon of Jupiter with a planet-wide ocean under a thick ice crust.
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Questions about large, dense, massive collections of stars orbiting galaxies, thought to have formed in the early universe.
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Questions about gas-giant planets in very close orbit to their parent star (closer than Mercury).
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Second lightest element in the periodic table
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track and display the current time.
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Questions regarding Charon, the largest satellite of the dwarf planet Pluto. Often considered to be Pluto's binary.
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Questions regarding a theoretical 'tunnel' through spacetime which could potentially allow time travel.
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like stars but never achieve nuclear fusion because they are too low-mass.
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the group of galaxies that includes the Milky Way among others.
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