In NASA spacesuits, communications are provided via a cap worn over the head, which includes earphones and a microphone. Due to the coloration of the version used for Apollo and Skylab, which resembled the coloration of the comic strip character Snoopy, these caps became known as "Snoopy caps".

The Apollo/Skylab A7L suit included eleven layers in all: an inner liner, a liquid cooling and ventilation garment, a pressure bladder, a restraint layer, another liner, and a thermal micrometeoroid garment consisting of five aluminized insulation layers and an external layer of white Ortho-Fabric.

Above Armstrong's Line (the altitude that produces an atmospheric pressure so low (0.0618 atmosphere) that water boils at the normal temperature of the human body: 37 °C (98.6 °F)~around 19,000 m/62,000 ft), the atmosphere is so thin that pressurized suits are needed.

The first space suit worn by a human in space was the Soviet Union SK-1 suit worn by Yuri Gargarin in 1961.

The first full pressure-suits for use at extreme altitudes were designed by individual inventors as early as the 1930s.

The analogue Mars Lander Habitat, commonly referred to as "The HAB", is a two story cylinder that measures about 10 meters (33 ft) in diameter and is a crew's combined home and place of work during a Mars surface exploration simulation.

MDRS crew members must wear an analogue space suit simulator or a "sim suit" when completing tasks outside the Habitat (HAB) to simulate the protection they would need from the in reality very harsh Martian environment.

The Mars Society launched the Mars Analog Research Station (MARS) Project in order to develop key knowledge needed to prepare for the human exploration of Mars.

The MDRS station is situated on the San Rafael Swell of southern Utah, located 11.63 kilometers (7.23 mi) by road north west of Hanksville, Utah.

The Mars Desert Research Station (MDRS) is the second of four planned simulated Mars surface exploration habitats (or Mars Analogue Research Stations) owned and operated by the Mars Society.

John Glenn found it hard to choke down his food, but not because of the lack of gravity: Early astronauts relied on aluminum tubes of semiliquid mush, food cubes, and dehydrated meals.

Contrary to Hollywood, though, you wouldn’t explode if you are ever exposed to the vacuum of space without a suit on. Lack of oxygen in the blood is what would kill you, but it would take about two minutes.

If you are ever exposed to the vacuum of space without a suit on, water on the tongue, in the nose, and in the eyes would boil away. This actually happened in 1965, when a space suit failed during a NASA experiment and the tester was exposed to a near vacuum for 15 seconds.

If you are ever exposed to the vacuum of space without a suit on, don’t hold your breath: Sudden decompression would cause your lungs to rupture.

At the start of the workday on the space shuttle, mission control in Houston broadcasts wake-up music, usually selected with a particular astronaut in mind. On the all-work, no-play International Space Station, crews wake to an alarm clock.

In weightlessness, fluids shift upward, causing nasal congestion and a puffy face; bones lose calcium, forming kidney stones; and muscles atrophy, slowing the bowels and shrinking the heart.

Nearly every astronaut experiences some space sickness, caused by the wildly confusing information reaching their inner ears. In addition to nausea, symptoms include headaches and trouble locating your own limbs.

A 2001 study showed that astronauts who snored on Earth snoozed silently in space. That's because gravity plays a dominant role in the generation of apneas, hypopneas, and snoring.

Without the compressive force of gravity while in orbit, your spinal column expands and you grow taller, usually by between 5 and 8 cm.

Orbiting the Earth, you will experience 16 sunrises and 16 sunsets every day.