Did you know?

11 September 2026

01
A giraffe's neck contains only seven vertebrae — the very same number found in a human neck. Each giraffe bone is simply far longer.
02
More than half of the oxygen in Earth's atmosphere comes from ocean microorganisms, not from land plants and forests.
03
Antarctica's ice sheet reaches about 4.8 kilometers thick in places. It holds more than half of all the fresh water on Earth.
04
Voyager 1, launched in 1977, is now more than 24 billion kilometers from Earth. It is the most distant human-made object in space.
05
An elephant's trunk contains about 40,000 muscles, letting it lift a heavy log and also delicately pick up a single blade of grass.
06
Jupiter has 95 officially confirmed moons — more than any other planet in the solar system.
07
Physicists have cooled matter in the laboratory to within a fraction of a billionth of a degree above absolute zero, colder than anywhere found naturally in space.
08
Sound cannot travel through the vacuum of space, because it needs molecules — like those in air or water — to carry its vibrations.
09
An adult tongue holds about 10,000 taste buds, and each one is fully replaced roughly every two weeks.
10
Mars has two small moons, Phobos and Deimos, both thought to be captured asteroids rather than moons that formed alongside the planet.
11
The Milky Way galaxy is about 100,000 light-years across, so light itself takes 100,000 years to cross from one edge to the other.
12
The computer that guided Apollo 11 to the Moon in 1969 was far less powerful than a modern pocket calculator.
13
Water is at its densest at 4 degrees Celsius, which is why ice, being less dense, floats on top of liquid water.
14
The axolotl, a Mexican salamander, can regrow an entire lost limb — including bone, muscle and nerves — within a few months.
15
The QWERTY keyboard layout was designed in the 1870s to keep frequently used typewriter keys apart and stop the mechanical arms from jamming.
16
Cats purr at a frequency of roughly 25 to 150 hertz, a range that has been shown to promote healing in bone and tissue.
17
Uranus spins almost completely on its side, tilted about 98 degrees, so it effectively rolls around the Sun rather than spinning upright like most planets.
18
On average, human head hair grows about 1 centimeter per month, or roughly 12 centimeters a year.
19
Human stomach acid has a pH of about 1.5 to 2, acidic enough to dissolve small pieces of metal over time.
20
An average adult human body contains about 5 liters of blood, roughly 7 to 8 percent of total body weight.
21
Earth's solid inner core is estimated to be about as hot as the surface of the Sun, roughly 5,500 degrees Celsius, yet it stays solid because of immense pressure.
22
Earth is home to more than 1,500 potentially active volcanoes on land, not counting the many more hidden beneath the oceans.
23
A single hedgehog can carry more than 5,000 spines on its back, each one a modified, stiffened hair.
24
Penguins do have knees — they are simply hidden beneath feathers and skin, folded up inside their compact, upright-looking legs.
25
The Great Barrier Reef, off Australia's coast, is the largest living structure on Earth, stretching about 2,300 kilometers.
26
Gram for gram, spider silk is stronger than steel, and some strands can stretch to several times their original length before breaking.
27
An adult human skeleton has 206 bones, but a newborn baby has about 300, many of which fuse together during childhood.
28
A chameleon can launch its tongue to strike prey in as little as 20 milliseconds — faster than the blink of a human eye.
29
About 73 percent of the human brain is water, which is why proper hydration matters for normal brain function.
30
The Grand Canyon was carved by the Colorado River over roughly the last 5 to 6 million years, even though the rock layers it cuts through are far older.