Could we live without the Moon and a magnetic field?

Credit: Earth Science and Remote Sensing Unit, NASA Johnson Space Center

Both the Moon and the Earth’s magnetic field have helped to keep our planet hospitable towards life. Think of that, next time you’re enjoying a romantic Full Moon or an aurora.

Field work: The Earth’s magnetic field is generated in its liquid outer mantle. The magnetic axis is slightly tilted with respect to the rotational axis.

Credit: Peter Reid

Lunar jump start: Tidal pools, produced by the Moon’s gravity, may have helped primitive life to spread from the oceans to the Earth’s surface.

Credit: Joaquim Alves Gaspar

Compared to the Earth, Mars is a very hostile place. The orientation of the planet’s rotational axis has changed dramatically in the geological past, causing catastrophic changes in climate. The planet’s surface is continuously bombarded by lethal particles, both from the Sun and from deep space. In contrast, Earth’s large Moon stabilises our planet and its climate. The magnetic field of the Earth shields us from cosmic rays and solar wind particles. Aurorae remind us that some particles still penetrate this magnetic shield: they cause the atmosphere to glow.

Colourful curtains: A colourful curtain of glowing oxygen atoms and nitrogen molecules marks the arrival of a solar storm of energetic particles.

Credit: Mia Stålnacke

Climate deal: The Earth’s relatively large and massive Moon helps to stabilise the planet’s rotational axis. Without the Moon, the Earth’s climate would be much more erratic over geological timescales.

Credit: G. Gillet/ESO

Aurora light show: The Earth’s magnetic eld shields us from most of the lethal energetic particles in the solar wind. The few that make it into the atmosphere produce beautiful aurorae.

Credit: design und mehr

Without the Moon, the Earth’s climate would become unstable. Without the Earth’s magnetic field, our planet would be bathed in deadly radiation. Thank you, Moon and magnetic field!