Do meteorites have aliens in them?
No living things, alien or otherwise, have ever been found in meteorites. But some meteorites contain chemicals that are building blocks of life.
It would be exciting to crack open a meteorite and find a tiny alien inside, but scientists have never found anything living in one.
Space is a very harsh place. It is freezing cold, it has no air to breathe and it is full of harmful rays from the Sun and stars. Then, when a space rock falls to Earth, its outside gets incredibly hot. Living things as we know them would find it very hard to survive.
However, some meteorites contain something almost as exciting: chemicals that living things are made from. A special kind called carbonaceous chondrites can contain water locked inside minerals, and carbon-based chemicals such as amino acids, which are the building blocks of proteins in your body. The Murchison meteorite, which fell in Australia in 1969, contains dozens of different amino acids. Samples brought back from the asteroids Ryugu and Bennu contain these chemicals too.
These discoveries suggest that space rocks may have helped bring some of the ingredients for life to the young Earth, billions of years ago. In 1996, scientists wondered whether a meteorite from Mars showed signs of tiny ancient microbes, but most now think the features were made without life. The search continues!