The Two Moons
Phobos
27 km across · orbits in just 7.7 hours — so close and fast it rises in the west and sets in the east twice a day, and is spiralling inward to break apart in ~50 million years.
Deimos
15 km across · orbits in 30.3 hours — a tiny, distant lump so small it would look like a bright star from the Martian surface.
Both moons are almost certainly captured asteroids — lumpy, dark, and far too small to be seen in amateur telescopes. They were discovered in 1877 and named for the sons of Ares (Mars): Fear and Dread.
The Planet Itself
Diameter
6,779 km
About half of Earth
Day length
24h 37m
Remarkably Earth-like
Year
687 days
Nearly two Earth years
Mars is red because its surface is literally rusted — iron-rich dust oxidised over billions of years. It carries the solar system’s record-holders: Olympus Mons, a volcano nearly three times the height of Everest, and Valles Marineris, a canyon system that would stretch across the entire United States. Through a small scope, look for the bright white polar cap and dark markings like Syrtis Major when Mars is near opposition.