Over time, even facts we consider steadfast truths can change. People used to think doctors could forgo washing their hands before surgery. Knowledge is ever-evolving.
The seven ideas below probably changed since your school days. Re-educate yourself.
THEN: Pluto is a planet
NOW: Pluto isn’t a planet
We’ve known since the late 1800s that a ninth planet, after Uranus, potentially existed. In 1906, Percival Lowell, the founder of the Lowell Observatory in Flagstaff, Arizona, even began a research project intended to locate the mysterious read more >>>