Are we witnessing a net gain or loss in Earth's mass?

Q: Are we witnessing a net gain or loss in Earth's mass?

Krishna:

Scientists "weigh" the Earth by using mathematical calculations based on Newton's Law of Universal Gravitation , which allows them to determine the Earth's mass by measuring the gravitational pull it exerts on known objects, like satellites or objects on its surface, combined with the Earth's radius, without actually putting the Earth on a scale. (2)

The uncertainty in the modern value for the Earth's mass has been entirely due to the uncertainty in the gravitational constant G since at least the 1960s. G is notoriously difficult to measure, and some high-precision measurements during the 1980s to 2010s have yielded mutually exclusive results. Accuracy has improved only slightly since then.

Earth's mass is variable, subject to both gain and loss due to the accretion of in-falling material, including micrometeorites and cosmic dust and the loss of hydrogen and helium gas, respectively. The combined effect is a net loss of material (3).

Yes, the weight of Earth keeps changing.

Various estimates state various things though.

The Earth gains about 40,000 to 50,000 tonnes of material each year from the accretion of meteoric dust and debris from space.

About 50,000 to 95,000 tonnes of hydrogen gas are lost from the Earth’s atmosphere to outer space each year.

The Earth’s core loses energy, since much of it is consumed in a planet’s lifespan, but that only accounts for a loss for about 16 metric tons per year. The biggest mass loss comes from escaped hydrogen and helium, which escape with 95,000 metric tons of mass and 1,600 metric tons respectively. These elements are too light to stay permanently in the gravity well, so they tend to escape into space.

The net loss is about 0.000000000000001% every year, so it doesn’t account for much when compared to the total mass of the Earth, which is 5,972,000,000,000,000,000,000 metric tons. It will take trillions of years for all of the hydrogen to be depleted. Helium represents 0.00052% of the atmosphere and it’s a scarcer element. (1)

Most estimates are that the Earth is losing more mass via atmospheric losses than it gains via cosmic dust, etc.

Although there are other processes involved, such as the loss of mass due to radioactive decay within the Earth’s core (about 160 tonnes a year), and helium loss from the atmosphere (about 1,600 tonnes a year), these are small effects. Annually, the amount of mass launched into Earth orbit is negligible by comparison,of the order of a few hundred tonnes.

When people build structures on Earth, it doesn’t add any mass since they are using baryonic matter that’s already present on the planet. It just changes shape. Launched satellites and rockets that end up in orbit will eventually fall towards Earth’s gravity well.

Footnotes:

1. https://scitechdaily.com/earth-loses-50000-tonnes-of-mass-every-year/
2. How do scientists measure or calculate the weight of a planet?
3. Earth mass - Wikipedia