Why did astronauts need spacesuits for a Moon landing?
The Moon has no atmosphere no air of any kind. Astronauts could have breathed by carrying tanks of oxygen, as sea divers do, but they faced other hazards that called for special suits.
Because the Moon has no air, the spacesuits were pressurised to keep each astronaut’s body at the normal atmospheric pressure on Earth of 1 kg per sq cm (14.7 lb per sq in). Had they stepped from their suits, the spacemen would have experienced something worse than the bends sometimes suffered by divers. Their bodies might have exploded.
The astronauts also had to be shielded from fierce heat. Even on Earth, dark coloured rocks, which absorb heat, can become too hot to handle. The Moon has no atmosphere to reduce the Sun’s energy, and in full sunlight the temperature rises to 110°C (230°F), higher than the boiling point of water.
Earth has a built in thermostat to control the Sun’s heat. Our atmosphere, mostly oxygen and nitrogen, warms up and carries heat away from hot land surfaces. Oceans cover 70 per cent of the Earth’s surface. Because water absorbs a great deal of heat before warming up, these vast seas effectively control sudden swings in temperature.
The Moon has none of these advantages. With no atmosphere to penetrate, the Sun’s intense ultraviolet light arrives unscreened. Spacesuits had special visors to filter out the UV rays. The garments’ thick fabric gave protection too against micrometeorites minute dust particles that hit the Moon at high speeds, sufficient to make a naked spaceman feel as though he’d entered a sandblaster.
Because the Moon has no air, the spacesuits were pressurised to keep each astronaut’s body at the normal atmospheric pressure on Earth of 1 kg per sq cm (14.7 lb per sq in). Had they stepped from their suits, the spacemen would have experienced something worse than the bends sometimes suffered by divers. Their bodies might have exploded.
The astronauts also had to be shielded from fierce heat. Even on Earth, dark coloured rocks, which absorb heat, can become too hot to handle. The Moon has no atmosphere to reduce the Sun’s energy, and in full sunlight the temperature rises to 110°C (230°F), higher than the boiling point of water.
Earth has a built in thermostat to control the Sun’s heat. Our atmosphere, mostly oxygen and nitrogen, warms up and carries heat away from hot land surfaces. Oceans cover 70 per cent of the Earth’s surface. Because water absorbs a great deal of heat before warming up, these vast seas effectively control sudden swings in temperature.
The Moon has none of these advantages. With no atmosphere to penetrate, the Sun’s intense ultraviolet light arrives unscreened. Spacesuits had special visors to filter out the UV rays. The garments’ thick fabric gave protection too against micrometeorites minute dust particles that hit the Moon at high speeds, sufficient to make a naked spaceman feel as though he’d entered a sandblaster.
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