The fourth planet from the Sun and the seventh largest is named Mars, this was the war god in Roman Mythology and Aries in the Greek. The red shine as Mars was observed by the naked eye in ancient times was like a drop of blood in the sky. These identify this with the God of War.
orbit: 227,940,000 km (1.52 AU) from Sun
diameter: 6,794 km
mass: 6.4219e23 kg
Mars is sometimes referred to as the Red Planet. A side note: the Roman god Mars was a god of agriculture before becoming associated with the Greek Ares. This symbolism my be prefered by Ttose in favor of colonizing and terraforming Mars. The name of the month March derives from Mars.
Since prehistoric times Mars has been seen and observed. Of course, it has been extensively studied with ground-based observatories. The big difficutly is that even very large telescopes find Mars a small target.
Even though modern space exploration has debunk the mysteries of the canals It is still a favorite of science fiction writers. Being the closest to Earth makes it the most as the most favorable place in the Solar System for human habitation.