Chthonian planets may be very dense worlds. They can be twice as dense as pure iron. This means that the acceleration due gravity is quite high at their surface. It is known that ‘every point mass attracts every single other point mass by a force pointing along the line intersecting both points’ (Wikipedia). The acceleration of today’s Earth is well known, the value is approximately:

**9.8 m/s ^{2}**

If we change the Earth’s radius to 5000 km, we get

**15.9 m/s ^{2}**,

which is 1.6 times more than today.

Although trilobites cannot be directly radiometrically dated, it is assumed that they are cambrian-permian ancient sea creatures (550-251 Ma). They can be found literally everywhere around the world – Germany, Poland, Czech Republic, Turkey, Canada, Brazil, United States. This means that all of these terrains were once flooded so that trilobites could exist.

If we work with Earth’s total primordial water (Earth’s icy sarcophagus) and expansion, one would expect that the smaller the planet, the more water on continental blocks when getting back into the past.

And that’s the problem. The rapid expansion started approximately 180 million years ago according to the data of the oceanic floor.

So we have got 2 options:

- The trilobite ages are wrong.
- The trilobite ages are right.

If they were wrong, then paleontology would have a problem. Actually, I am still waiting for a relevant answer here:

If they were right, then trilobites would live in a inhospitable environment with higher gravity values at the sarcophagus/crust interface, which is highly improbable.

The last option would be that the map of ocean floor ages is wrong and the ages are actually higher, which is also highly improbable.