Two worlds humans plan to live on this century. One is three days away, the other is nine months. Nine rounds head to head — and the winner flips halfway through.
The Moon sits 384,400 km out and Apollo crews flew it in three days. Mars averages 225 million km, and a crewed ship needs roughly seven to nine months each way.
Lunar gravity is one sixth of Earth's; Mars gives you 38 percent. An 80 kg astronaut presses down like 13 kg on the Moon, 30 kg on Mars. Bone and muscle prefer Mars.
A Martian sol runs 24 hours 39 minutes — almost the rhythm you were born with. The Moon turns once a month: 14 days of unbroken sunlight, then 14 of darkness.
Lunar noon reaches 127°C and lunar night drops to −173°C at the equator. Mars averages −63°C but can climb near 20°C on a summer afternoon. Mars swings far less.
The Moon has essentially no air at all. Mars has 0.6 percent of Earth's pressure and 95 percent carbon dioxide — still unbreathable, but enough to brake a landing craft.
Neither world has a magnetic shield. Chang'e-4 measured 1.37 millisieverts a day on the Moon; Curiosity logged about 0.7 on Mars. Thin Martian air halves the dose.
Both hide ice. The Moon's is locked in polar craters that have not seen sunlight in billions of years. Mars keeps buried sheets and caps, some barely a metre down.
Moon dust is glass-sharp and static-clingy; it chewed through Apollo suit seals in three days. Mars dust is finer, laced with perchlorates, and its storms run for months.
Radio crosses to the Moon in 1.3 seconds, so a real conversation works. Mars runs 3 to 22 minutes each way: every exchange is a message, never a call. Help is never fast.
The Moon is far easier to reach — and easier to flee. Mars is easier to survive once you arrive: kinder gravity, a familiar day, milder cold, half the radiation.