Howardites
Beginner · Lesson 4 of 10

When a meteorite falls

What really happens when a space rock falls to the ground? The answer might surprise you.

Into the air

A meteoroid big enough to make a meteorite is usually at least the size of a fist, and often much larger. It enters the air at many kilometres per second. The air in front of it is squeezed and heated so much that it glows, making a bright fireball. The outside of the rock melts and is blown away, a little bit at a time.

The air acts like a giant brake. Within a few seconds the rock slows down dramatically. Often it also breaks into pieces, because the pressure of the air is too much for it. Most of the original rock is lost, burned off or turned to dust. Only a small part usually reaches the ground. Very often, more than nine tenths of the original rock never reaches the ground at all.

Dark flight

When the rock has slowed down enough, usually somewhere between about 15 and 30 kilometres up, it stops glowing. From then on it just falls, like a stone dropped from a very tall tower. Scientists call this part of the journey dark flight, because the rock can no longer be seen.

During dark flight the wind can push the falling pieces sideways. That makes it tricky to know exactly where they will land. Heavy pieces travel further along the path, while lighter ones land earlier. When a rock breaks up, its pieces are scattered over an oval-shaped area on the ground called a strewn field.

People nearby may hear sonic booms, like thunder, and sometimes whistling or buzzing sounds as the pieces fall.

Hot or cold?

In cartoons, meteorites land glowing red hot and set things on fire. In real life that almost never happens. The fiery part of the journey only lasts a few seconds, so the heat does not have time to soak far into the rock. The thin melted skin cools down during dark flight.

The inside of the rock has been in the deep cold of space for millions of years. People who picked up meteorites just after they landed have usually said they felt cool or only slightly warm.

Most small meteorites land at the speed of a falling stone, a few hundred kilometres per hour at most, and make only a small dent. Only very rare, very large space rocks keep enough speed to dig a big crater.

Did you know?

Did you know?

A meteorite seen falling and then collected is called a fall. One found later, without anyone seeing it land, is called a find.

Did you know?

In 2021 a meteorite landed on a driveway in Winchcombe, in Gloucestershire, England, and many of its pieces were collected within days.

Try this

Drop a feather, a sheet of paper and a rubber from the same height. Which lands first? Now scrunch the paper into a ball and try again. The air slows things down, just as it slows falling meteoroids.

Quick quiz

4 questions. Choose an answer to find out whether you are right.

  1. Question 1What is the dark flight part of a meteorite's fall?

  2. Question 2Are freshly fallen small meteorites usually red hot?

  3. Question 3What is a strewn field?

  4. Question 4What slows a meteoroid down as it falls?