Moon had a magnetic field for at least a billion years longer than thought
An analysis of an Apollo rock suggests two ways such a small body generated its field
The moon had a magnetic field for at least 2 billion years, or maybe longer.
Analysis of a relatively young rock collected by Apollo astronauts reveals the moon had a weak magnetic field until 1 billion to 2.5 billion years ago, at least a billion years later than previous data showed. Extending this lifetime offers insights into how small bodies generate magnetic fields, researchers report August 9 in Science Advances. The result may also suggest how life could survive on tiny planets or moons.