Well I'd go further, we haven't even started on the Moon. Just a few astronauts spent a few days there. They were most of them, jet fighter pilots, acting under guidance from Earth with low quality real time video. We have only ever sent one geologist to the Moon and he had two days there. We have only been to the flattest safest parts of the Moon. The Chinese mission was the first lander on the Moon for decades and it didn't travel far. We have never explored the lunar poles which are in permanent darkness and can't be seen in our photographs but believed to contain layers of icy dust.
There's much we can do usefully on the Moon also, far side especially is an ideal place to build telescopes, starting with easy to construct long wave radio telescopes - just wires rolled over the surface. to observe the universe without interference from Earth. We can only do radio astronomy in a few radio bands from Earth and even then always have the possibility of interference, even from things like microwaves accidentally leaking into radio telescope wavelengths.
There are probably meteorites on the surface of the Moon from early Earth - or else buried deep below the surface, so can search to find those - they could give our only direct evidence of the mysterious first few hundred million years on Earth when life started - all we have left on Earth are a few zircons from that time. The ice deposits at the poles might also hold valuable evidence from those times, depending how they were deposited.
We should explore Mars - but only from orbit. Mars and Europa are the two places in the solar system that should be put off limits to humans until we find out if there is life there already, if it is interestingly different, and to have at least some idea of what would happen to them if Earth life is introduced to them - long term - as it might have long term consequences, very probably would. Within a decade a lifeform introduced to Mars could spread over the entire planet.
Meanwhile, if prospective explorers don't find the Moon interesting, they probably would get bored of Mars within a few days or weeks.
There's much we can do usefully on the Moon also, far side especially is an ideal place to build telescopes, starting with easy to construct long wave radio telescopes - just wires rolled over the surface. to observe the universe without interference from Earth. We can only do radio astronomy in a few radio bands from Earth and even then always have the possibility of interference, even from things like microwaves accidentally leaking into radio telescope wavelengths.
There are probably meteorites on the surface of the Moon from early Earth - or else buried deep below the surface, so can search to find those - they could give our only direct evidence of the mysterious first few hundred million years on Earth when life started - all we have left on Earth are a few zircons from that time. The ice deposits at the poles might also hold valuable evidence from those times, depending how they were deposited.
We should explore Mars - but only from orbit. Mars and Europa are the two places in the solar system that should be put off limits to humans until we find out if there is life there already, if it is interestingly different, and to have at least some idea of what would happen to them if Earth life is introduced to them - long term - as it might have long term consequences, very probably would. Within a decade a lifeform introduced to Mars could spread over the entire planet.
Meanwhile, if prospective explorers don't find the Moon interesting, they probably would get bored of Mars within a few days or weeks.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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