A planet, like everything material in the Universe, is expected to decay in time. The rate of this decay, however, depends on a number of factors.

For example, 1 gram of plutonium can be expected to decay for many thousands of years. But, 1 kg of plutonium will not last even 10 milliseconds... When a radioactive isotope reaches so-called "critical mass" - it explodes.

Can we guarantee that our reckless abuse and overheating of Earth does not increase the probability of radioactive isotopes in the Earth's core reaching critical mass?

The story of Phaeton proves that existence of a planet in our Solar System cannot be taken for granted...

Do we need planet Earth? Maybe we don't...