All 8 facts in this deck
Prefer to read them all at once? Here they are, each with its source.
Does lightning strike the same place twice?
Lightning often hits the same spot again and again. The old saying 'lightning never strikes twice' is wrong. Lightning follows the easiest path to the ground, and tall, pointed, isolated objects offer exactly that, storm after storm. Skyscrapers, radio towers and lone trees get struck again and again.
Takeaway: A spot that was struck once is not safe. Tall, isolated things attract repeat strikes.
Source: Lightning Myths and Facts — National Weather Service (NOAA), checked 2026-10-21.
Is lightning hotter than the Sun?
A lightning bolt is about five times hotter than the Sun's surface. As a lightning channel forms, it heats the air around it to roughly 50,000°F (about 27,700°C) in a split second. The visible surface of the Sun is only about a fifth of that. The sudden heat makes the air expand violently, and that shock wave is the thunder you hear.
Takeaway: Thunder is the sound of air heated hotter than the Sun's surface in an instant.
Source: Understanding Lightning: Overview — National Weather Service (NOAA), checked 2026-10-21.
What is heat lightning?
"Heat lightning" is just lightning from a storm too far to hear. There is no special kind of lightning caused by hot summer nights. Those silent flashes on the horizon come from an ordinary thunderstorm that is simply far enough away that its thunder fades before reaching you. Often you are seeing the light bounce off high clouds, not the bolt itself.
Takeaway: Silent flashes mean a real storm is out there, and it may be heading your way.
Source: Heat Lightning — National Weather Service (NOAA), checked 2026-10-21.
What shape are raindrops?
Falling raindrops look like hamburger buns, not teardrops. The classic teardrop shape is an illustrator's invention. Very small raindrops are round, held together by surface tension. Bigger drops get flattened on the bottom by air pushing up against them as they fall, so they end up domed on top and flat underneath, much like a burger bun.
Takeaway: Next time you draw rain, round it off and flatten the bottom.
Source: Are Raindrops Shaped Like Teardrops? — U.S. Geological Survey, checked 2026-10-21.
Is old window glass thicker at the bottom because glass flows?
Old windows aren't thicker at the bottom because glass flows. A popular story says glass is a super-slow liquid that sags over centuries. Penn State researchers ran the numbers using the recipe of medieval glass from Westminster Abbey and found any flow at room temperature is far too slow to change a pane's shape. The likelier culprit is old glassmaking, which produced uneven sheets.
Takeaway: Uneven antique panes tell you about the glassmaker, not about glass melting.
Source: Researcher uses Westminster Abbey windows to shine light on glass myth — Penn State University, checked 2026-10-21.
Does water boil at a lower temperature at high altitude?
Water boils at a lower temperature the higher up you go. Water boils when its vapour pressure matches the air pressure pushing down on it. High up there is less air above you, so water boils at a lower temperature. At 5,000 feet (about 1,500 m) it boils at about 95°C (203°F) instead of 100°C, so pasta and eggs take longer to cook.
Takeaway: In the mountains, boiling water is cooler, so add cooking time.
Source: Facts About Water — U.S. Geological Survey, checked 2026-10-21.
Are rainbows actually full circles?
Every rainbow is really a full circle. Sunlight bounces inside raindrops at a fixed angle, so the colours always form a ring around the point directly opposite the Sun. From the ground, the land cuts the ring off, so you usually see an arc. From a plane or a drone high above the rain, you can sometimes see the whole circle.
Takeaway: Window seat on a rainy-day flight? Look for a complete circular rainbow.
Source: APOD: A Full Circle Rainbow over Norway (2022 Dec 27) — NASA Science (Astronomy Picture of the Day), checked 2026-10-21.
Do microwaves cook food from the inside out?
Microwaves don't cook food from the inside out. Microwaves make water molecules in food vibrate, which creates heat inside the food. But the waves mostly reach only the outer couple of centimetres. In anything thick, the middle warms up only as heat spreads inward, which is why the centre of leftovers can stay cold.
Takeaway: Stir halfway and let food stand a minute so heat can spread to the middle.
Source: Microwave Ovens — U.S. Food and Drug Administration, checked 2026-10-21.