"Lion"

The modern Earth's atmosphere is so rich in oxygen that the vast majority of this hydrogen will be re-oxidized to water without escaping from the Earth's top atmosphere

Nowadays, Mars is obviously unsuitable for direct human habitation, because the environment of Mars is very different from that of Earth, such as Mars is unusually arid, desolate and without a trace of life. Despite this, scientists are still keen to explore Mars

Although the Earth is just a "grain of dust suspended in the sun" in the universe, for us humans, this "grain of dust" is irreplaceable.