Lots
It does get sun but not as much as mercury and Venus
We can see them when they are above the horizon and the Sun is below the horizon. They still receive sunlight when we are having our night-time, and what we see is the part of the planet that is in sunlight. Jupiter is brighter because it is very much bigger, despite being a lot further away.
About half the amount of sunlight reaches the surface of Mars compared to Earth, due to its greater distance from the Sun. The thin atmosphere on Mars also scatters and absorbs some of the sunlight before it reaches the surface.
"When H.G. Wells wrote about invaders from Mars, not much was known about the planet."
Mars is slightly preferable to a space colony or a dome on the Moon or Mercury, because it has water and carbon dioxide for growing plants. But it does not receive nearly as much sunlight as Mercury. The alternative would be a floating colony within Venus's atmosphere (sealed habitats with Earth-normal pressure would float in the dense atmosphere).
Not much gas at all, as Mars is a rocky planet with not much of an atmosphere.
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Neptune is much colder than Mars.
Uranus is much larger than Mars. Uranus is the seventh planet from the Sun and is classified as an ice giant, while Mars is the fourth planet from the Sun and is known as the "Red Planet".
Mars. Not Mars. Jupiter is a lot bigger than Earth, but the Sun is much bigger than a planet.
The polar regions never receive any direct sunlight.
Mars comes the closest.