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What would happen if Earth suddenly doubled in size?

Imagine if the Earth’s density remained the same but its radius doubled, resulting in an eightfold increase in the planet’s mass. If our planet truly doubled in size, would we have more living space? What interesting changes would occur for humans and other creatures? Let’s delve into it!

Plant Life Fades Quickly

When Earth’s gravitational force doubles, most plant species would wither and die rapidly. Many tall plants would break due to increased gravity. The reason is that taller plants require more energy to transport water from their roots to the top. If the energy needed for water transportation exceeds the energy gained through photosynthesis, plants cease to grow and instead shrink.

Larger Animals Lose Mobility

Any animals larger than or equal to the size of a dog would be unable to run and jump without breaking their leg bones. Large predators would struggle to chase down their prey. In general, the process of evolution would accelerate, and natural selection would become much more pronounced.



Human Bodies Become Burdensome

If Earth’s diameter doubled, the planet’s mass would increase by a factor of eight, resulting in twice the gravitational force. Consequently, the weight of the human body would double. This would make you feel like you’re carrying another person on your back, making everything more challenging and exhausting.

Under the influence of this increased gravity, the human body would move more slowly, making walking, running, and jumping difficult. Additionally, physical activities would quickly lead to exhaustion.

A Day Becomes Longer than a Month

If the atmosphere doubled in size along with Earth’s diameter, air pressure would also double. The brains of humans and other animals would require more blood. However, this change would benefit birds, as flying would become much easier.



With Earth doubling in size, the planet’s rotation would slow down by a factor of 32. Instead of a 24-hour day, a day would last over a month. Consequently, the temperature imbalance between light and darkness on the planet would be immense, resulting in flattening winds strong enough to level buildings.

Mass Extinction Event

The most horrifying consequence of Earth “growing up” would be geological upheaval. The increased mass of radioactive elements in the mantle would make the magma hotter. Hundreds of new volcanoes would form and erupt, pumping vast amounts of CO2 into the atmosphere, creating an unprecedented greenhouse effect. A mass extinction event of catastrophic proportions would occur, with nothing able to prevent it.