Back again with something really interesting and cool : Spacesuits!
So, everyone knows what is a space suit. It is something that an astronaut wears while he is space. But, do you know what goes into a space suit or why he requires it? Let’s find out!
So, when you go in space, you encounter a variety of dangerous things that might just kill you. These include, but are not limited to,
- Lack of an atmosphere-death by asphyxiation
- Cosmic Rays and Solar Radiation-death by radiation
- Micrometeoroids- death by punching a hole through you!
- Absolute coldness and vacuum-death by freezing or depressurization
So to stay alive in space, you will need to have a form of protection that covers your body. That is your spacesuit.
Contrary to popular belief, spacesuits need not be worn all the time. They are only required when the astronaut goes out of the Space Station for a spacewalk or for any other Extra-Vehicular Activity (EVA). When the astronaut is within the space station, he/she is perfectly safe.
So what is this magical suit made up of?
A spacesuit is basically a personal spacecraft for the astronaut. It should provide him with all the requisites to stay alive. These include warmth, insulation, protection from radiation and micro meteors and some means of navigating or moving as required. It should also have some media for communicating with Earth and the Space Station and also some means of attaching the astronaut to the spacecraft so that he/she does not float away into space. Also, the suit must be able to absorb any human bodily wastes for later disposal.
The designing of a spacesuit is a very difficult job. This is primarily due to the fact that, countering all the above hazards require layers and layers of insulating material which protects the astronaut inside it but at the same time, it restricts his/her mobility. This can be very frustrating for the astronaut as he will have to constantly apply efforts against his/her suit. But, over time, humans have figured out a way around this.
While early space suits were made entirely of soft fabrics, today’s Extravehicular Mobility Unit (EMU) has a combination of soft and hard components to provide support, mobility and comfort. The suit itself has 13 layers of material, including an inner cooling garment (two layers), pressure garment (two layers), thermal micrometeoroid garment (eight layers) and outer cover (one layer).The suit itself weighs 127kg(on Earth!) and is about 0.5 cm thick. Each space suit costs $12 million to manufacture! The materials used include Nylon,ricot,Spandex, Urethane-coated Nylon, Dacron, Neoprene-coated Nylon, Mylar, Gortex, Kevlar (material in bullet-proof vests) and Nomex.
All of the layers are sewn and cemented together to form the suit. In contrast to early space suits, which were individually tailored for each astronaut, the EMU has component pieces of varying sizes that can be put together to fit any given astronaut.
The EMU consists of the following parts:
The Primary/Personal/Portable Life Support System (PLSS) : The PLSS is a form of backpack that is worn by the astronaut. It contains essential systems such as the oxygen supply, two way voice communication system and the air handling unit which maintains the flow of oxygen through the pressure garment and eliminates odour, CO2 and humidity from it.
Liquid Cooling and Ventilation Garment : This is basically a high tech undergarment. It is made up of very stretchy spandex material with lots of tubes underneath it. The tubes contain chilled water which is pumped through the entire suit to prevent discomfort to the astronaut. The garment contains vents all over which allow transfer of sweat.
Secondary Oxygen Pack (SOP) : The SOP is an emergency oxygen supply that fits below the PLSS on the backpack frame. It has two oxygen tanks that contain a total of 2.6 lb (1.2 kg) at 408 atm tank pressure. This is enough oxygen for 30 minutes, which is sufficient time to get a crewmember back inside the spacecraft. This oxygen supply automatically turns on when the oxygen pressure in the suit drops below 0.23 atm.
Communications Carrier Assembly(CCA) : The CCA is a cap which is worn under the helmet. It contains earphones and microphones which connects the rest of the crew and the Earth Control to the astronaut. Because of its distinctive resemblance to the cartoon character Snoopy, this cap is called the Snoopy Cap!
elmet : The high strength, clear polycarbonate Helmet covers the astronaut’s head. It keeps the pressure around the head stable and provides a continuous supply of oxygen. The helmet is covered by a Visor made of gold, which filters out the radiation from the sun. The visor is bulletproof and protects the astronauts from microscopic dust particles that may hit him/her. The helmet also contains mounting spaces for cameras which allows broadcasting and recording footage. The modern helmets worn by most astronauts also have a built in Velcro patch which is extremely useful if the astronaut has a sudden urge to scratch his/her nose!
Upper Torso and Arm Assembly: This is the top of the spacesuit and covers the entire upper body and the upper arms of the astronaut. It is a vest made up of fiberglass and acts as a base onto which the PLSS and the Display and Control Module attaches to. The arm assembly is also similiarly made and can be adjusted for size by the astronaut.
Gloves : To do stuff in outer space, the astronauts need maximum mobility of their hands. This is provided by the glove assembly. The gloves are highly insulated and are also provided with heaters in the finger tips due to the fingers being the parts that get coldest in space. The gloves are designed to resist puncturing and provide optimum flexibility but at the cost of strength. The wrist part contains ball bearings to ease the movement of the wrists.
Displays and Control Module(DCM) : This module is the control panel for the mini-spacecraft. The DCM is a chest-mounted unit. It contains all of the switches, gauges, valves and LCD displays necessary to operate the PLSS.
Sleeve-mounted Mirrors and Checklists : These devices fit over the sleeves of the EMU. The mirrors help the astronauts see the DCM displays and see behind them. The checklists help them remember procedures over the course of a seven-hour spacewalk.
In-suit Drink Bag : This is a plastic pouch filled with water that is attached to the inside of the torso unit by Velcro. The bag has a straw with a valve attached to it at the end. The valve is actuated when the astronaut bites on it and releasing the bite closes the valve.
Lower Torso Assembly : This is the bottom section of the space suit. This includes the pants, knee joints, boots and the tether unit. This unit attaches to the upper torso by a metal body seal. It also has D-rings at the lower waist to attach the tethers. The torso unit has different coloured stripes that allow the crew members to be distinguished from one another.
Maximum Absorption Garment : Because spacewalks typically last more than six hours without a break, spacewalkers wear adult-sized diapers with extra absorption material under their spacesuits.
Simplified Aid for EVA Rescue : SAFER is like a life jacket. Spacewalkers working on the space station wear SAFER. Astronauts are usually connected to the station by a tether. If an astronaut should become untethered and float away, SAFER would help her or him fly back to the station. SAFER is worn like a backpack. It uses small nitrogen-jet thrusters to let an astronaut move around in space. Astronauts can control SAFER with a small joystick.
Well, that’s all for this post. Hope you enjoyed reading this!
Until Next Time!