Mars
Mars is the fourth planet of our Solar System and the last of the planets of the inner Solar System. Its orbit around the Sun takes 1,88 years to complete, while turning around itself takes 24 hours and 40 minutes, time similar to Earth. Mars's axis is tilted similar to Earth, giving it the opportunity to have seasons. Temperatures on the surface vary from -143 °C in the winter at the poles and reach a maximum of 35 °C in the equatorial areas.
By the first observations with a telescope Mars stimulated people's imagination as its surface looked similar to Earth, it has valleys and volcanic mountains, regions of different colors and clouds, and ice at its poles. After 1960, when the first Mariner space missions arrived there, expectations for a welcoming planet for us disappeared.
Mars is a planet with several craters, some rather inactive volcanoes that have renewed its surface in the past. Its red color is due to the oxidation of iron on its surface. It is speculated that in the past this planet had water in liquid form as there are signs of rivers that no longer have water. We now know that there is water in the form of ice but also in liquid form in the “summer” in the form of impurities, since pure water evaporates at such a low pressure (1% of Earth’s pressure) (https://www.nasa.gov/press-release/nasa-confirms-evidence-that-liquid-water-flows-on-today-s-mars).
Its core is solid and consists mainly of iron and nickel but is not surrounded by liquid outer core, so Mars does not have a magnetic field like Earth capable of protecting it from the solar wind. It is believed that in the past when its core had not cooled, it had a magnetic field that could protect its atmosphere from being swept by the solar wind. As soon as the magnetic field was extinct, the atmosphere had begun to drift in to space steadily reducing the pressure on the surface of Mars, causing the water to evaporate or subside.
It’s atmosphere is composed of about 96% carbon dioxide, 1,93% argon and 1,89% nitrogen with traces of oxygen and water. It is quite dusty and contains microparticles that make the color of the Martian sky orange rather than light blue.
On Mars, one will meet Mount Olympus, the largest volcano ant the second highest mountain in the Solar System, as well as Valles Marineris, one of the largest canyons in our Solar System. One may also meet one of the Rovers or Landers that are constantly studying its surface.
It has two satellites, Phobos and Dimos, which are small and irregular in shape. They look like asteroids.