What If on MSN
What if scientists proved Planet X is real?
Over the past century, astronomers have speculated about the existence of a mysterious 9th planet lurking in the outer ...
About 65 million years ago, a mass extinction event occurred, wiping out more than 75% of all species on Earth. There have ...
What if the Earth were actually for sale? It sounds absurd, but we decided to take the idea at face value. If someone tried to put a price tag on Earth, what would that number even be based on? Land, ...
There may be a warp in the Kuiper Belt, possibly caused by “Planet Y” — a Mercury-to-Earth-sized world that orbits the sun way beyond the orbit of Neptune. Is there a mysterious “Planet Y” orbiting ...
A nearby Earth-sized planet offers a rare chance to study how atmospheres survive or disappear on rocky worlds.
NASA and other space agencies track thousands of near-Earth objects like this one. There are more than 41,000 known near-Earth asteroids that come relatively close to Earth’s orbit, and scientists are ...
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