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Based on the article provided, here is the information regarding Earth's mass changes:
Earth's Mass Balance Sheet
The Earth is currently a net loser of mass, though the amounts are minuscule compared to its total size.
| Source of Change | Amount (Approx. Annual) | Key Details |
| Mass Loss | -100,000 tonnes | Primarily light gases (hydrogen and helium) escaping the upper atmosphere. |
| Mass Gain | +40,000 to 50,000 tonnes | Mostly in the form of meteorites and cosmic dust. |
| Spacecraft | -65 tonnes | Satellites and probes sent on escape trajectories that never return. |
| Net Result | -50,000 to 60,000 tonnes | A net decline, which is roughly $8.4 \times 10^{-18}\%$ of Earth's total mass. |
The Big Picture
While losing 60,000 tonnes a year sounds significant, the article puts it into perspective:
Over the 4.54 billion years of Earth's existence, the total loss is only about 45 parts per billion.
In human terms, this loss relative to Earth's mass is equivalent to losing 360 people out of a global population of 8 billion.
This is "repaid" in cosmic history; for example, the collision with Theia (the Mars-sized object that helped form the Moon) likely increased Earth's mass by about 10% in one go.
Why do we lose gas?
Gas molecules at a specific temperature move at varying speeds. Some light molecules (like hydrogen) reach speeds exceeding Earth's escape velocity:
Once they reach this speed in the upper atmosphere, they can break free from Earth's gravity and drift into space.
Would you like me to summarize the other section of the article about why we can't just "jump up" and let the Earth spin beneath us to travel?
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