Physics
Glass is not a slow-flowing liquid
Old cathedral windows are thicker at the bottom because of how they were made, not because glass flows. At room temperature glass is a solid.
More in Physics
Sunlight you see is 8 minutes old
Light needs about 8 minutes and 20 seconds to cross 150 million kilometres, so you always see the Sun as it was, never as it is.
Lightning is five times hotter than the Sun
A bolt of lightning heats the air around it to about 30,000°C — roughly five times hotter than the surface of the Sun. That sudden heat is what makes the thunderclap.
Sound travels four times faster in water
Water molecules sit closer together than air molecules, so vibrations pass along faster — about 1,480 m/s versus 343 m/s.
Glass is not a liquid
Old window panes are thick at the bottom because of how they were made, not because glass flows. Glass is an amorphous solid.