Medieval philosophers debated universe's finite or infinite past. Robert Grosseteste described universe's birth in 1225. Einstein's general relativity showed universe's expanding nature
Earth was initially believed to be the center of the universe. Heliocentric model revealed Sun's position in disc-shaped galaxy. By 20th century, Milky Way galaxy was one of billions in expanding universe. Universe became clearer with superclusters forming filaments and voids
Earth is the third planet from the Sun and the only known life-bearing object. The planet has an average diameter of 12,742 km and is the densest in the Solar System. Earth's surface is 70.8% ocean water and 29.2% land. The planet is spherical with a circumference of about 40,000 km
Speed of light is the universe's maximum speed. In vacuum, light travels at 299,792,458 m/s or 670,616,629 mph. Light travels faster in air than in water due to refraction
Hogwarts was founded by four great British witches over 1,000 years ago. Each house represents a founder's philosophy and values. Students are sorted into houses during the Sorting Hat ceremony
GQ Lupi b is the largest exoplanet, with a radius 3.5 times Jupiter's. UY Scuti is the largest star, 1,700 times larger than the sun