The Impact of a Global Mass Event on Earth's Mass

Has it ever occurred to you what would happen to Earth if all people were to die simultaneously? Often pondered, this scenario invites a deep dive into the conservation of mass, atmospheric dynamics, and the ongoing changes in our planet's mass. Let's explore these concepts and the implications of such an event.

Understanding Mass and Atmospheric Dynamics

The Earth is a fascinating system, constantly experiencing a net loss of mass each year due to gas escaping into space. Each year, the Earth loses about 50,000 tons of atmospheric gases, compensating for this by receiving approximately 40,000 tons from meteorites and dust. This results in a net loss of around 10,000 tons annually. Sometimes, the loss is even more significant, as seen with the Apollo program, where a small amount, equivalent to a few hundred pounds, was added to Earth's mass due to space missions and fuel.

With humans contributing to this mass balance, primarily through spacecraft and fuel reaching escape velocity, the Earth is always undergoing a subtle change in mass. However, if all humans were to perish suddenly, this activity would cease, resulting in no significant change in the net loss of mass.

External Factors and Mass Change

A critical question here is whether any external factors could cause a change in the Earth's mass. One scenario that could affect the mass is the occurrence of a catastrophic event, such as a meteor impact. If a meteor struck Earth, it would eject material, increasing the mass of the Earth by the mass of the asteroid, but at the same time, it would also decrease the mass through the ejection of debris. This would temporarily increase the Earth's total mass.

Another consideration is the possible increase in atmospheric density after a global mass event. Human activities, such as industrial processes, contribute to the release of various gases, including free hydrogen and helium. These gases can be lost into space, making the atmosphere lighter. The cessation of human activity might initially lead to a denser atmosphere, but in the long term, the activity could be taken over by other life forms, potentially leading to a decrease in atmospheric loss.

Decay and Long-Term Changes

A key point is that the mass of corpses would begin to decay and decompose, eventually releasing gases, liquids, and solids back into the biosphere. This decomposition would not significantly alter the total mass of the planet.

For any significant mass change to occur, there would need to be a large-scale event where mass is either added by external factors (like a meteor impact) or removed by converting mass into energy. The latter, if it were to happen suddenly, could indeed cause a significant change in mass and energy, much like the explosive effects of a large-scale conversion event.

Conclusion

In summary, a global mass event such as the death of all people would not significantly change the Earth's total mass. The key factors to consider are the ongoing processes of mass loss through gas escape and any additional mass added through external events like meteor impacts. While there might be temporary changes, the overall mass of the Earth would remain largely constant, except for the minor fluctuations caused by natural and human-induced processes.