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Not a fact anymore
Earth rotates once each day and orbits the Sun once each year. The other planets also orbit the Sun, while the solar system itself orbits within the Milky Way.
Not a fact anymore
Mercury rotates three times for every two orbits around the Sun. It is in a 3:2 spin-orbit resonance, so every part of the planet experiences daylight over time.
Not a fact anymore
The Milky Way is one galaxy among an enormous population of other galaxies spread throughout the observable universe.
Not a fact anymore
Under the International Astronomical Union's 2006 definition, Pluto is a dwarf planet because it has not cleared the neighbourhood around its orbit. The Solar System has eight objects formally classified as planets.
Not a fact anymore
Observations of distant Type Ia supernovae show that the expansion of the universe is accelerating. The cause is described as dark energy, although its physical nature remains unknown.