Mars is the most habitable planet in our solar system because of the following:
1. Mars soil contains water to extract.
2. Temperature was so good same like Planet Earth. It isnt too cold or too hot.
3. Solar panels can gather enough of Sunlight to produce Solar Energy.
4. Gravity is adoptable and its 38% that of Earth's gravity which is believed by many to be sufficient for the human body to adapt to
5. The atmosphere offers protection from cosmic and Sun's radiation.
6.The day/night rhythm is very similar to Earth: a Mars day is 24 hours, 39 minutes and 35 seconds
2. Temperature is far colder than Earth in places, and never nearly as warm as Earth is in some places.
4. We don't really know if Mars gravity will be good for people in the long run.
5. The atmosphere offers a little radiation protection, but far less than we need, or other forms of life need.
7. There is no recorded life of any sort on Mars... that we know of. Plants can only grow in the presence of humus. At least small amounts of living bacteria of the kind that form humus must be present for plants to live and survive. Naturally, solar radiation would kill off any humus bacteria living near the surface of the soil.
8. There is essentially no natural magnetic field on Mars as there is on Earth. We haven't lived outside of a magnetic field, so we don't know if we would be harmed without one. Certainly the tiny magnetic field on Mars isn't enough to ward of space radiation like it does on Earth.
It will be a far harder job to make Mars habitable than we imagine. We might live within enclosed habitats, but it will take decades or centuries to make Mars naturally habitable.