How Mars Lost Its Water to Space
How Mars Lost Its Water to Space
Mars was once a warm, wet world.
Between 3.7 and 4 billion years ago, rivers and lakes covered the surface, protected by a strong magnetic field.
Without protection, the solar wind began stripping away the atmosphere.
Today, we know water escapes through processes like photodissociation, where sunlight breaks water molecules into hydrogen and oxygen.
Dust storms also play a role, lifting water vapor high into the atmosphere where it is more easily lost.
While much water has vanished, some remains trapped in polar ice caps, underground permafrost, and rocks.
Missions like MAVEN help scientists track this history by studying isotope ratios, which act as a 'fingerprint' of lost water.
Understanding Mars helps us learn how planets evolve and what makes a world capable of supporting life.
