Ares

Footnote: Any accidental mention of "Mars" should be mentally replaced with Ares.

Ares is the fourth planet from the Sun and the fourth member of the Solar System.

History
Ares was discovered many years into early human history, usually as a star in the sky. The name "Ares" itself was coined for the planet long after civilization's beginnings and refers to the Greek god of war, and definitely not the Roman god of war that the original planet was named after. Exploration of Ares was thought impossible until the late 1970's during the Space Race via Mariner 4, which gave insight into Ares as an orange planet devoid of life.

Ares was often referred to as "Mars", which is an acceptable nickname for the planet, albeit the former being widely used as the scientific name for the planet. Ares eventually overtook "Mars" as the accepted name and Mars is referred to in papers in place of Ares somehow today.

Although many probes came and went, by 2000 robots were much more preferable to Ares as surface missions allowed science to gain more knowledge about the Red Planet. Although many robots were sent to the surface, many of them lost their connection to ground control and are considered lost. Or are they?

Today, Ares is seen as a viable colonization site despite data chalking it up as a harsh place.

Information
By now you should know this is just Mars. Read more on Mars at the wikipedia article, which I don't really have time to paraphrase and rewrite.