Mars Basics

Size & Distance

Smaller than Earth (0.532x)Mars diam ~ 6779 km (4212

miles)Earth diam ~ 12,742 km

(7918 miles)8 Mars would fit inside the

Earth!

Size & Distance

Size & Distance Smaller than Earth (0.532x)

Mars diam ~ 6779 km (4212 miles) Earth diam ~ 12,742 km (7918

miles) 8 Mars would fit inside the Earth!

1.5 AU from the sun (~140 million miles)

0.5 AU from the Earth (~43 million miles)

SCALE!!!

Scale

Using a 12-inch Earth globe and 6-inch Mars globe as a scale:

Q: How far away do you think Mars would be?

A: 1.4 km (~0.87 miles)

LPI

McDonald’s

Rotation & Revolution

One Martian day (sol) is 24 hours and 37 minutes

One Martian year is 687 Earth days, almost two Earth years

Seasons

Like Earth, Mars tiltsThis tilt contributes to seasons, orbit also contributes

Atmosphere

Yep. Mars has an atmosphere.

~95% CO2, ~3% N2, ~2% Ar; traces of O2, CO

Surface pressure ~0.006 atm (~1/100th Earth’s atmosphere)

Gerard Kuiper made spectroscopic observations of CO2 in the atmosphere in 1952; presumed to be a minor constituent until 1965

Interior

Core, mantle, crust

No magnetic field today; data support one in the past

Mars is ColdAverage temp: -63° C (max & min vary)

Weirdness above the surface…

Deimos – 15 km (9.3 miles)

Phobos – 26.8 km (16.7 miles)

Moons