Heat and matter

Mars is cold: about −60 °C on average, and the air is so thin that water boils away at a few degrees above freezing. This topic starts with hot and cold and climbs to temperature scales, heat flow, the gas laws and phase diagrams, the physics behind keeping people warm and water liquid on Mars.

8 levels. The ages are only a rough guide for parents and teachers; anyone can start at any level.

Level	Rough age	What it covers
Level 1: Hot and cold	5-6	Feeling hot and cold, thermometers, keeping warm
Level 2: Solid, liquid, gas	7-8	Melting, freezing, boiling, ice and steam
Level 3: Heat on the move	9-10	Conduction, convection, radiation; why a blanket works
Level 4: Temperature, measured	11-12	Celsius and kelvin, specific heat, the cold of a Mars night
Level 5: Pressure and gases	12-13	Pressure as force per area, the 6 hPa air of Mars, gas laws
Level 6: Phase changes	13-14	Latent heat, why water boils at low pressure, the triple point
Level 7: Insulating a home	15-16	Heat loss through walls, regolith shielding as insulation, a heating budget
Level 8: Thermodynamics	17 and beyond	The laws of thermodynamics, heat pumps, engines and the climate of Mars