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OSIRIS Mars true color.jpg

Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury. In English, Mars carries a name of the Roman god of war, and is often referred to as the "Red Planet" because the reddish iron oxide prevalent on its surface gives it a reddish appearance that is distinctive among the astronomical bodies visible to the naked eye. Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the valleys, deserts, and polar ice caps of Earth.

The rotational period and seasonal cycles of Mars are likewise similar to those of Earth, as is the tilt that produces the seasons. Mars is the site of Olympus Mons, the largest volcano and second-highest known mountain in the Solar System, and of Valles Marineris, one of the largest canyons in the Solar System. The smooth Borealis basin in the northern hemisphere covers 40% of the planet and may be a giant impact feature. Mars has two moons, Phobos and Deimos, which are small and irregularly shaped. These may be captured asteroids, similar to 5261 Eureka, a Mars trojan.

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In the news

13 February 2019 – Exploration of Mars
The mission of NASA's Opportunity rover on Mars comes to an end. The rover stopped communicating in June 2018 after a Martian dust storm, and attempts to reestablish communications have not been successful. (NASA)
11 February 2019 –
Mars One, a private Dutch organization that had claimed it would send humans on a one-way trip to Mars starting in 2024, releases a statement saying it has been declared bankrupt. (CBC)



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