Orion is the state of the art spacecraft that NASA will employ to launch astronauts on their deep space mission to Mars. The gringa wants to know the most important bits about this vehicle and how it will keep astronauts safe and healthy on such an amazing journey. The most important things necessary for survival and comfort will be a propulsion system, heat and radiation shielding, re-entry braking system, clean water, breathable air, climate control and, as unglamorous as it is to mention such a thing, a toilet.
The first thing the crew will have to do is get off the ground and out of Earth’s atmosphere. The propulsion system that achieves this will also be responsible for a safe return trip home as well as any course corrections in the midst of traversing back and forth. NASA is collaborating with the European Space Agency (ESA) to develop such a service model for the Orion spacecraft. It will contain the propulsion system, solar arrays and batteries. It will be the power generator and also contain the reservoirs of air, water and nitrogen that will be used by the crew.
Deep space travel as well as re-entry is when Orion will encounter deadly radiation and overwhelming heat. During periods of most intense heat and radiation exposure, there is an area in the aft bay of Orion that is used temporarily during these critical periods. This section of the spaceship is nearest the heat shield. The ship is configured in such a way that while sheltering in this spot, there is a maximum amount of other material and equipment between astronauts and the outside elements. The most important components of this area are the supplies and equipment needed for launch and re-entry as well as food and water provisions. This design configuration helps to maximize protection with what is already on board rather than increase the mass of the ship.
In 2014 the heat shield was put to the test on Orion on a test flight. The spacecraft successfully held up under temperatures in excess of 4,000 degrees Fahrenheit. The heat shield surrounds a skeleton constructed of titanium with a supportive skin of carbon fiber. A honeycomb type structure is fitted over the skin. The cells of the honeycomb are filled with “Avcoat” up to a thickness of almost two inches. This protective coating gradually erodes as it blasts back home through Earth’s atmosphere. Avcoat, developed in partnership with Textron Defense Systems that is based in Massachusetts, is a silica fiber and epoxy-novalic resin substance. It has proved its true grit on multiple NASA missions like the robotic exploration of a comet on the automated NASA exploration vessel Stardust as well as being used successfully on the Apollo mission. There was stiff competition to be selected as the product NASA would use in the construction of the heat shield. Avcoat proved its mettle time and again.
Once the crew has successfully and safely broken free of Earth’s atmosphere, it’s time to settle in for the long haul. The environmental life support and control system currently used on the International Space Station (ISS) is the model Orion’s support system is based on. On Orion carbon dioxide, the waste product from the astronauts respiration, will be recycled and converted into useable air. As NASA continues work on Orion’s life support system, they are using amine and the natural vacuum of space to filter and recycle the air. Amine is a derivative of ammonia, which is present in urine. Not only will the astronaut’s urine be recycled to produce clean, drinkable water, but the ammonia can also be filtered out, separated and then used to help produce breathable air. The gringa can only think, “Waste not, want not, right?”
When the crew completes their mission and returns to Earth, they will need one more thing to help them in the final splashdown, a parachute braking system. Now, parachutes seem to be such a common piece of equipment that have been around for a long time, what could possibly be left to discover or upgrade? Well, considering re-entry can reach speeds in the thousands of miles per hour range and, to splashdown safely needs to slow down to the low hundreds of miles per hour, NASA’s parachutes are definitely in a class by themselves. Orion will pack away eleven parachutes in all that will deploy in a precisely choreographed parachute dance. Three will be located on top of the ship, two will be located in critical areas for stabilization, and then three pilot parachutes will pull out the three primary braking chutes. These “brakes” are so big, that, when bundled together above the capsule, they cover an area almost the size of a football field.
The gringa can’t wait for the day when the world’s most powerful rocket blasts off into outer space with what I consider to be a crew of the bravest souls ever. It is unbelievable to see how far exploration has come since the days of Leif Erikson or Lewis and Clark.
Source and Photo Credit: http://www.nasa.gov