Observations show the disk of our galaxy is not flat but warped and waving. Astronomers are still working out the reasons why ...
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If Mars and Venus were still habitable today, life would thrive
Mars and Venus once had oceans and atmospheres, and if still habitable, humans could have colonized multiple planets and ...
Explore the Earth and Mars comparison to discover why Earth is the perfect habitable planet, uniquely sustaining life on ...
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