Gravity on Mars

The diameter of Mars is a little over half that of Earth. Using the standard model of gravity and assuming all else to be equal between Mars and Earth, Mars' surface gravity should be a little over half that of Earth. This is because the standard model of gravity predicts a linear relationship between diameter and surface gravity for objects of the same density.

However, Mars is a red planet. It has a surface rich in iron, so its surface is more dense than that of Earth which is less rich in iron. Assuming that surface density is an indication of the density throughout the planet, surface gravity on Mars should come out a little stronger than what is predicted based purely on its diameter. A surface gravity at about 60% of what we have on Earth would be a reasonable estimate.

Using the same logic, we see that our Moon has a diameter a little over half that of Mars, so its surface gravity should be a little over half that of Mars based solely on diameter. However, the Moon, like Earth, has a surface with little iron in it. This should reduce the surface gravity a little relative to Mars, making it pretty much exactly half that of Mars.

As it turns out, surface gravity on the Moon is 44% that of Mars, a little less than we would expect based solely on diameter and apparent density. However, surface gravity on Mars is a mere 38% that of Earth, way less than the 60% expected.

The low surface gravity on Mars is truly perplexing in light of the standard model. The only way to explain this is that Earth must have a super-dense core, and hence we have come to believe that all planets, and our own planet in particular, is composed of matter that increases in density as we get closer to the core.

However, recent measurements of Jupiter, using a microwave gun attached to the space probe Juno, indicate that Jupiter is less dense in its interior compared to its outer layers. Jupiter appears to be hollow.

The only gravity model that predicted the hollow found at the core of Jupiter is the capacitor model, and it turns out that this same model can also explain why Mars has such a low surface gravity relative to Earth.

What makes Earth and Mars very different is not the makeup of their surface, but the fact that Earth appears to have grown from a Mars size planet to the size it has today. Earth has increased its capacitance due to its expansion, and capacitance increases exponentially with diameter. Instead of a linear increase in gravity relative to diameter, there has been an exponential increase in gravity relative to diameter.

The predictions of the capacitor model is that Earth should have significantly higher surface gravity than Mars due to its significantly higher capacitance. Likewise, Mars which shows some sign of initial expansion (Valles Marineris), should have a somewhat higher than expected surface gravity relative to our Moon which shows no sign of expansion.

Using the capacitor model of gravity, everything adds up. There is no need for a super-dense core at the center of our planet, and the recent discovery that Jupiter is hollow is a confirmation of the model's validity.

Mars

By NASA / USGS (see PIA04304 catalog page) - http://nssdc.gsfc.nasa.gov/photo_gallery/photogallery-mars.html http://nssdc.gsfc.nasa.gov/image/planetary/mars/marsglobe1.jpg, Public Domain, Link