Science myths
Science is a special magnet for confident misconceptions—half-remembered from school, half-invented by intuition. A friendly correction service:
Body & biology
Myth
The claim: Deoxygenated blood is blue.
Actually: Human blood is always red — bright when oxygenated, dark red when not. Veins look bluish through skin due to how light penetrates tissue, not blue blood.
Myth
The claim: Humans have just five senses.
Actually: We have many more — balance, temperature, pain, body position (proprioception), and others. 'Five senses' is a useful oversimplification, not the full count.
Myth
The claim: Humans evolved from chimpanzees.
Actually: We didn't. Humans and chimps share a common ancestor and evolved along separate branches — chimps are cousins, not grandparents.
Physics & space
Myth
The claim: Seasons are caused by Earth's distance from the Sun.
Actually: They're caused by Earth's axial tilt. (When the Northern Hemisphere has summer, Earth is actually slightly farther from the Sun.)
Myth
The claim: There's no gravity in space.
Actually: Gravity is everywhere — astronauts on the ISS are in constant free-fall around Earth, which feels weightless. It's not the absence of gravity.
Myth
The claim: A penny dropped from a skyscraper could kill someone.
Actually: A penny's shape and low terminal velocity mean it would sting at most — it can't reach lethal speed falling through air.
Everyday science
Myth
The claim: Water drains the opposite way in different hemispheres (Coriolis).
Actually: The Coriolis effect is far too weak to determine which way your sink or toilet drains — basin shape and water jets decide that.
Myth
The claim: Glass is a slow-moving liquid (that's why old windows are thicker at the bottom).
Actually: Glass is an amorphous solid, not a slow liquid. Old windows vary in thickness because of how they were historically made.
More history-flavored wrongness next door: history myths.