Misplaced Pages

#421578

131-435: A life-support system is the combination of equipment that allows survival in an environment or situation that would not support that life in its absence. It is generally applied to systems supporting human life in situations where the outside environment is hostile, such as outer space or underwater , or medical situations where the health of the person is compromised to the extent that the risk of death would be high without

262-673: A saturation diving system is considered a life-support system – the personnel who are responsible for operating it are called life support technicians . The concept can also be extended to submarines , crewed submersibles and atmospheric diving suits , where the breathing gas requires treatment to remain respirable, and the occupants are isolated from the outside ambient pressure and temperature. Medical life-support systems include heart-lung machines , medical ventilators and dialysis equipment. A crewmember of typical size requires approximately 5 kilograms (11 lb) of food , water , and oxygen per day to perform standard activities on

393-424: A spacecraft must travel faster than a sub-orbital spaceflight along an arcing trajectory . The energy required to reach Earth orbital velocity at an altitude of 600 km (370 mi) is about 36  MJ /kg, which is six times the energy needed merely to climb to the corresponding altitude. The escape velocity required to pull free of Earth's gravitational field altogether and move into interplanetary space

524-515: A closed loop, new elements found on site can be brought into the system. Outer space Outer space (or simply space ) is the expanse that exists beyond Earth's atmosphere and between celestial bodies . It contains ultra-low levels of particle densities , constituting a near-perfect vacuum of predominantly hydrogen and helium plasma , permeated by electromagnetic radiation , cosmic rays , neutrinos , magnetic fields and dust . The baseline temperature of outer space, as set by

655-586: A connection to septic tanks or sewer systems unlike flush toilets . Common applications include national parks , remote holiday cottages, ecotourism resorts, off-grid homes and rural areas in developing countries . The term "composting toilet" is used quite loosely, and its meaning varies by country. For example, in Germany and Scandinavian countries, composting always refers to a predominantly aerobic process. This aerobic composting may take place with an increase in temperature due to microbial action, or without

786-536: A consistent and relatively high moisture content. Some composting toilets are designed with urine diversion . Commercial units and construct-it-yourself systems are available. Variations include number of composting vaults, removable vault, urine diversion and active mixing/aeration. Most composting toilets use slow composting which is also called "cold composting". The compost heap is built up step by step over time. The finished end product from "slow" composting toilets ("moldering toilets" or "moldering privies" in

917-580: A container within the toilet unit. They are slightly larger than a flush toilet , but use roughly the same floor space. Some units use fans for aeration, and optionally, heating elements to maintain optimum temperatures to hasten the composting process and to evaporate urine and other moisture. Operators of composting toilets commonly add a small amount of absorbent carbon material (such as untreated sawdust , coconut coir , or peat moss ) after each use to create air pockets to encourage aerobic processing, to absorb liquid and to create an odor barrier. This additive

1048-471: A density of one proton per four cubic meters. The density of the universe is clearly not uniform; it ranges from relatively high density in galaxies—including very high density in structures within galaxies, such as planets, stars, and black holes —to conditions in vast voids that have much lower density, at least in terms of visible matter. Unlike matter and dark matter, dark energy seems not to be concentrated in galaxies: although dark energy may account for

1179-545: A dry, odorless material which is very different to the wet fecal sludge produced in pit latrines which has to be taken care of through a fecal sludge management system. Composting toilets do not cause groundwater pollution due to their safe containment of feces in above-ground vaults compared to pit latrines, allowing composting toilets to be sited in locations where pit-based systems are not appropriate. Composting toilets may have higher capital costs than pit latrines, but lower lifecycle costs. They require more involvement by

1310-519: A hazard to astronauts, even in low Earth orbit. They create aurorae seen at high latitudes in an oval surrounding the geomagnetic poles . xGeo space is a concept used by the US to refer to space of high Earth orbits , ranging from beyond geosynchronous orbit (GEO) at approximately 35,786 km (22,236 mi), out to the L2 Earth-Moon Lagrange point at 448,900 km (278,934 mi). This

1441-556: A higher nutrient availability than the dried feces that result from a urine-diverting dry toilet . Urine is typically present, although some is lost via leaching and evaporation. Urine can contain up to 90 percent of the residual nitrogen , up to 50 percent of the phosphorus , and up to 70 percent of the potassium . Compost derived from these toilets has in principle the same uses as compost derived from other organic waste products, such as sewage sludge or municipal organic waste. However, users of waste-derived compost must consider

SECTION 10

#1732851337422

1572-464: A highly integrated and reliable system: Air temperature control, Humidity removal, Carbon dioxide removal , Trace contaminant removal, Post-fire atmospheric recovery, Air filtration, and Cabin air circulation. Space station systems include technology that enables humans to live in outer space for a prolonged period of time. Such technology includes filtration systems for human waste disposal and air production. Skylab used 72% oxygen and 28% nitrogen at

1703-411: A long beam extending another cabin section or counterweight, spinning it at an appropriate speed will cause centrifugal force to simulate the effect of gravity. If ω is the angular velocity of the ship's spin, then the acceleration at a radius r is: Notice the magnitude of this effect varies with the radius of rotation, which crewmembers might find inconvenient depending on the cabin design. Also,

1834-507: A majority of the mass-energy in the universe, dark energy's influence is 5 orders of magnitude smaller than the influence of gravity from matter and dark matter within the Milky Way. Outer space is the closest known approximation to a perfect vacuum . It has effectively no friction , allowing stars, planets , and moons to move freely along their ideal orbits , following the initial formation stage. The deep vacuum of intergalactic space

1965-502: A perigee as low as 80 to 90 km (50 to 56 mi), surviving for multiple orbits. At an altitude of 120 km (75 mi), descending spacecraft such as NASA 's Space Shuttle begin atmospheric entry (termed the Entry Interface), when atmospheric drag becomes noticeable, thus beginning the process of switching from steering with thrusters to maneuvering with aerodynamic control surfaces. The Kármán line , established by

2096-412: A place to sit or squat and a collection/composting unit. The composting unit consists of four main parts: Many composting toilets collect urine in the same chamber as feces, thus they do not divert urine . Adding small amounts of water that is used for anal cleansing is no problem for the composting toilet to handle. Some composting toilets divert urine (and water used for anal washing) to prevent

2227-483: A plumbing and mechanical code structure adopted by many developed countries. It recently proposed an addition to its "Green Plumbing Mechanical Code Supplement" that, "...outlines performance criteria for site built composting toilets with and without urine diversion and manufactured composting toilets." If adopted, this composting and urine diversion toilet code (the first of its kind in the United States) will appear in

2358-636: A practical boundary have been proposed, ranging from 30 km (19 mi) out to 1,600,000 km (990,000 mi). High-altitude aircraft , such as high-altitude balloons have reached altitudes above Earth of up to 50 km. Up until 2021, the United States designated people who travel above an altitude of 50 mi (80 km) as astronauts. Astronaut wings are now only awarded to spacecraft crew members that "demonstrated activities during flight that were essential to public safety, or contributed to human space flight safety." In 2009, measurements of

2489-481: A simulated Martian environment. The lithopanspermia hypothesis suggests that rocks ejected into outer space from life-harboring planets may successfully transport life forms to another habitable world. A conjecture is that just such a scenario occurred early in the history of the Solar System, with potentially microorganism -bearing rocks being exchanged between Venus, Earth, and Mars. The lack of pressure in space

2620-552: A space mission, and outputs a similar amount in the form of waste solids, waste liquids, and carbon dioxide . The mass breakdown of these metabolic parameters is as follows: 0.84 kg (1.9 lb) of oxygen, 0.62 kg (1.4 lb) of food, and 3.54 kg (7.8 lb) of water consumed, converted through the body's physiological processes to 0.11 kg (3.9 oz) of solid wastes, 3.89 kg (8.6 lb) of liquid wastes, and 1.00 kg (2.20 lb) of carbon dioxide produced. These levels can vary due to activity level of

2751-643: A spacecraft; similarly, " space-based " means based in outer space or on a planet or moon. The size of the whole universe is unknown, and it might be infinite in extent. According to the Big Bang theory, the very early universe was an extremely hot and dense state about 13.8 billion years ago which rapidly expanded . About 380,000 years later the universe had cooled sufficiently to allow protons and electrons to combine and form hydrogen—the so-called recombination epoch . When this happened, matter and energy became decoupled, allowing photons to travel freely through

SECTION 20

#1732851337422

2882-575: A specific mission assignment, but must obey the principle of mass balance . Actual water use during space missions is typically double the given value, mainly due to non-biological use (e.g. showering). Additionally, the volume and variety of waste products varies with mission duration to include hair, finger nails, skin flaking, and other biological wastes in missions exceeding one week in length. Other environmental considerations such as radiation, gravity, noise, vibration, and lighting also factor into human physiological response in outer space, though not with

3013-410: A surface saturation accommodation facility provides breathing gas and other services to support life for the personnel under pressure. It includes the following components: Underwater habitats differ in that the ambient external pressure is the same as internal pressure, so some engineering problems are simplified. Underwater habitats balance internal pressure with the ambient external pressure, allowing

3144-469: A temperature increase in the case of slow composting or cold composting. If earth worms are used ( vermicomposting ) then there is also no increase in temperature. Composting toilets differ from pit latrines and arborloos , which use less controlled decomposition and may not protect groundwater from nutrient or pathogen contamination or provide optimal nutrient recycling. They also differ from urine-diverting dry toilets (UDDTs) where pathogen reduction

3275-652: A total pressure of 5 psi. The Salyut and Mir space stations contained an air-like Oxygen and Nitrogen mixture at approximately sea-level pressures of 93.1 kPa (13.5psi) to 129 kPa (18.8 psi) with an Oxygen content of 21% to 40%. The life-support system for the Bigelow Commercial Space Station is being designed by Bigelow Aerospace in Las Vegas, Nevada . The space station will be constructed of habitable Sundancer and BA 330 expandable spacecraft modules. As of October 2010, " human-in-the-loop testing of

3406-539: A tree. The composting chamber can be constructed above or below ground level. It can be inside a structure or include a separate superstructure. A drainage system removes leachate . Otherwise, excess moisture can cause anaerobic conditions and impede decomposition. Urine diversion can improve compost quality, since urine contains large amounts of ammonia that inhibits microbiological activity. Composting toilets greatly reduce human waste volumes through psychrophilic , thermophilic or mesophilic composting. Keeping

3537-451: Is a European Space Agency led initiative, conceived as a micro-organisms and higher plants based ecosystem intended as a tool to gain understanding of the behaviour of artificial ecosystems, and for the development of the technology for a future regenerative life-support system for long term crewed space missions. CyBLiSS ("Cyanobacterium-Based Life Support Systems") is a concept developed by researchers from several space agencies ( NASA ,

3668-433: Is a humus -like material, which can be suitable as a soil amendment for agriculture. Compost from residential composting toilets can be used in domestic gardens, and this is the main such use. Enriching soil with compost adds substantial nitrogen, phosphorus, potassium, carbon and calcium. In this regard compost is equivalent to many fertilizers and manures purchased in garden stores. Compost from composting toilets has

3799-469: Is a continuous stream of charged particles emanating from the Sun which creates a very tenuous atmosphere (the heliosphere ) for billions of kilometers into space. This wind has a particle density of 5–10 protons /cm and is moving at a velocity of 350–400 km/s (780,000–890,000 mph). Interplanetary space extends out to the heliopause where the influence of the galactic environment starts to dominate over

3930-492: Is about 11,200 m/s (40,300 km/h; 25,100 mph). Orbiting spacecraft with a perigee below about 2,000 km (1,200 mi) are subject to drag from the Earth's atmosphere, which decreases the orbital altitude. The rate of orbital decay depends on the satellite's cross-sectional area and mass, as well as variations in the air density of the upper atmosphere. At altitudes above 800 km (500 mi), orbital lifetime

4061-501: Is about five times the Moon's orbital distance , but which distance is also far less than the distance between Earth and any adjacent planet. Interplanetary space within the Solar System is the space between the eight planets, the space between the planets and the Sun, as well as that space beyond the orbit of the outermost planet Neptune where the solar wind remains active. The solar wind

Life-support system - Misplaced Pages Continue

4192-445: Is achieved through dehydration (also known by the more precise term " desiccation ") and where the feces collection vault is kept as dry as possible. Composting toilets aim to have a certain degree of moisture in the composting chamber. Composting toilets can be used to implement an ecological sanitation approach for resource recovery , and some people call their composting toilet designs "ecosan toilets" for that reason. However, this

4323-540: Is added after each use. This practice creates air pockets in the human waste to promote aerobic decomposition. This also improves the carbon-to-nitrogen ratio and reduces potential odor . Most composting toilet systems rely on mesophilic composting. Longer retention time in the composting chamber also facilitates pathogen die-off. The end product can also be moved to a secondary system – usually another composting step – to allow more time for mesophilic composting to further reduce pathogens. Composting toilets, together with

4454-457: Is co-populated by groups of co-orbital Near-Earth Objects (NEOs), such as horseshoe librators and Earth trojans , with some NEOs at times becoming temporary satellites and quasi-moons to Earth. Deep space is defined by the United States government as all of outer space which lies further from Earth than a typical low-Earth-orbit, thus assigning the Moon to deep-space. Other definitions vary

4585-411: Is consumed by crew members for drinking, cleaning activities, EVA thermal control, and emergency uses. It must be stored, used, and reclaimed (from waste water and exhaled water vapor) efficiently since no on-site sources currently exist for the environments reached in the course of human space exploration. Future lunar missions may utilize water sourced from polar ices; Mars missions may utilize water from

4716-529: Is conventionally used as the start of outer space in space treaties and for aerospace records keeping. Certain portions of the upper stratosphere and the mesosphere are sometimes referred to as "near space". The framework for international space law was established by the Outer Space Treaty , which entered into force on 10 October 1967. This treaty precludes any claims of national sovereignty and permits all states to freely explore outer space . Despite

4847-680: Is critical to ensure proper operation, including odor prevention. Maintenance tasks include: cleaning, servicing technical components such as fans and removal of compost, leachate and urine. Urine removal is only required for those types of composting toilets using urine diversion. Once composting is complete (or earlier), the compost must be removed from the unit. How often this occurs is a function of container size, usage and composting conditions, such as temperature. Active, hot composting may require months, while passive, cold composting may require years. Properly managed units yield output volumes of about 10% of inputs. The material from composting toilets

4978-496: Is divided into overlapping regions of space. Near-Earth space is the region of space extending from low Earth orbits out to geostationary orbits . This region includes the major orbits for artificial satellites and is the site of most of humanity's space activity. The region has seen high levels of space debris, sometimes dubbed space pollution , threatening any space activity in this region. Some of this debris re-enters Earth's atmosphere periodically. Although it meets

5109-399: Is done, for example, by composting toilets which reintegrate waste material (excrement) back into the system, allowing the nutrients to be taken up by the food crops. The food coming from the crops is then consumed again by the system's users and the cycle continues. The logistics and area requirements involved however have been prohibitive in implementing such a system to date. Depending on

5240-438: Is free for all nation states to explore and is not subject to claims of national sovereignty, calling outer space the "province of all mankind". This status as a common heritage of mankind has been used, though not without opposition, to enforce the right to access and shared use of outer space for all nations equally, particularly non-spacefaring nations. It prohibits the deployment of nuclear weapons in outer space. The treaty

5371-487: Is located beyond the orbit of the Moon and therefore includes cislunar space. Translunar space is the region of lunar transfer orbits , between the Moon and Earth. Cislunar space is a region outside of Earth that includes lunar orbits , the Moon's orbital space around Earth and the Lagrange points . The region where a body's gravitational potential remains dominant against gravitational potentials from other bodies,

Life-support system - Misplaced Pages Continue

5502-401: Is meant to be used in conjunction with ISO 24511. It deals with toilets (including composting toilets) and toilet waste. The guidelines are applicable to basic wastewater systems and include the complete domestic wastewater cycle, such as planning, usability, operation and maintenance, disposal, reuse and health. The International Association of Plumbing and Mechanical Officials (IAPMO) is

5633-475: Is measured in centuries. Below about 300 km (190 mi), decay becomes more rapid with lifetimes measured in days. Once a satellite descends to 180 km (110 mi), it has only hours before it vaporizes in the atmosphere. Space in proximity to the Earth is physically similar to the remainder of interplanetary space, but is home to a multitude of Earth–orbiting satellites and has been subject to extensive studies. For identification purposes, this volume

5764-422: Is measured in terms of the kinetic activity of the gas, as it is on Earth. The radiation of outer space has a different temperature than the kinetic temperature of the gas, meaning that the gas and radiation are not in thermodynamic equilibrium . All of the observable universe is filled with photons that were created during the Big Bang, which is known as the cosmic microwave background radiation (CMB). (There

5895-449: Is not devoid of matter , as it contains a few hydrogen atoms per cubic meter. By comparison, the air humans breathe contains about 10 molecules per cubic meter. The low density of matter in outer space means that electromagnetic radiation can travel great distances without being scattered: the mean free path of a photon in intergalactic space is about 10  km, or 10 billion light years. In spite of this, extinction , which

6026-484: Is not odorous. Waste-derived compost recycles fecal nutrients, but it can carry and spread pathogens if the process of reuse of waste is not done properly. Pathogen destruction rates in composting toilets are usually low, particularly of helminth eggs (such as those from the genus Ascaris ). This carries the risk of spreading disease if a proper system management is not in place. Compost from human waste processed under only mesophilic conditions or taken directly from

6157-436: Is not recommended as the two terms (i.e. composting and ecosan) are not identical. Composting toilets have also been called "sawdust toilets", which can be appropriate if the amount of aerobic composting taking place in the toilet's container is very limited. The " Clivus multrum " is a type of composting toilet which has a large composting chamber below the toilet seat and also receives undigested organic material to increase

6288-551: Is quite likely a correspondingly large number of neutrinos called the cosmic neutrino background . ) The current black body temperature of the background radiation is about 2.7 K (−455 °F). The gas temperatures in outer space can vary widely. For example, the temperature in the Boomerang Nebula is 1 K (−458 °F), while the solar corona reaches temperatures over 1,200,000–2,600,000 K (2,200,000–4,700,000 °F). Magnetic fields have been detected in

6419-631: Is slowed by the pressure containment of blood vessels, so some blood remains liquid. Swelling and ebullism can be reduced by containment in a pressure suit . The Crew Altitude Protection Suit (CAPS), a fitted elastic garment designed in the 1960s for astronauts, prevents ebullism at pressures as low as 2 kilopascals (0.3 psi). Supplemental oxygen is needed at 8 km (5 mi) to provide enough oxygen for breathing and to prevent water loss, while above 20 km (12 mi) pressure suits are essential to prevent ebullism. Most space suits use around 30–39 kilopascals (4–6 psi) of pure oxygen, about

6550-465: Is sometimes referred to as "bulking agent". Some owner-operators use microbial "starter" cultures to ensure composting bacteria are in the process, although this is not critical. A vermifilter toilet is a composting toilet with flushing water where earthworms are used to promote decomposition to compost. It can be connected to a low-flush or a micro-flush toilet which uses about 500 millilitres (17 US fl oz) per use. Solids accumulate on

6681-538: Is the absorption and scattering of photons by dust and gas, is an important factor in galactic and intergalactic astronomy . Stars, planets, and moons retain their atmospheres by gravitational attraction. Atmospheres have no clearly delineated upper boundary: the density of atmospheric gas gradually decreases with distance from the object until it becomes indistinguishable from outer space. The Earth's atmospheric pressure drops to about 0.032 Pa at 100 kilometres (62 miles) of altitude, compared to 100,000 Pa for

SECTION 50

#1732851337422

6812-447: Is the body's sphere of influence or gravity well, mostly described with the Hill sphere model. In the case of Earth this includes all space from the Earth to a distance of roughly 1% of the mean distance from Earth to the Sun, or 1.5 million km (0.93 million mi). Beyond Earth's Hill sphere extends along Earth's orbital path its orbital and co-orbital space. This space

6943-504: Is the most immediate dangerous characteristic of space to humans. Pressure decreases above Earth, reaching a level at an altitude of around 19.14 km (11.89 mi) that matches the vapor pressure of water at the temperature of the human body . This pressure level is called the Armstrong line , named after American physician Harry G. Armstrong . At or above the Armstrong line, fluids in

7074-554: The Andromeda Galaxy was first measured. Humans began the physical exploration of space later in the same century with the advent of high-altitude balloon flights . This was followed by crewed rocket flights and, then, crewed Earth orbit, first achieved by Yuri Gagarin of the Soviet Union in 1961. The economic cost of putting objects, including humans, into space is very high, limiting human spaceflight to low Earth orbit and

7205-467: The Bogotá Declaration , they claimed control of the segment of the geosynchronous orbital path corresponding to each country. These claims are not internationally accepted. An increasing issue of international space law and regulation has been the dangers of the growing number of space debris . A spacecraft enters orbit when its centripetal acceleration due to gravity is less than or equal to

7336-549: The Fédération Aéronautique Internationale , and used internationally by the United Nations , is set at an altitude of 100 km (62 mi) as a working definition for the boundary between aeronautics and astronautics. This line is named after Theodore von Kármán , who argued for an altitude where a vehicle would have to travel faster than orbital velocity to derive sufficient aerodynamic lift from

7467-794: The German Aerospace Center and the Italian Space Agency ) which would use cyanobacteria to process resources available on Mars directly into useful products, and into substrates for other key organisms of Bioregenerative life support system (BLSS). The goal is to make future human-occupied outposts on Mars as independent of Earth as possible (explorers living "off the land"), to reduce mission costs and increase safety. Even though developed independently, CyBLiSS would be complementary to other BLSS projects (such as MELiSSA) as it can connect them to materials found on Mars, thereby making them sustainable and expandable there. Instead of relying on

7598-551: The International Union of Pure and Applied Chemistry (IUPAC) definition of standard pressure . Above this altitude, isotropic gas pressure rapidly becomes insignificant when compared to radiation pressure from the Sun and the dynamic pressure of the solar wind . The thermosphere in this range has large gradients of pressure, temperature and composition, and varies greatly due to space weather . The temperature of outer space

7729-443: The Moon . On the other hand, uncrewed spacecraft have reached all of the known planets in the Solar System . Outer space represents a challenging environment for human exploration because of the hazards of vacuum and radiation . Microgravity has a negative effect on human physiology that causes both muscle atrophy and bone loss . The use of the short version space , as meaning 'the region beyond Earth's sky', predates

7860-567: The Soyuz spacecraft is called the Kompleks Sredstv Obespecheniya Zhiznideyatelnosti (KSOZh) ( Russian : Комплекс Средств Обеспечения Жизнедеятельности (KCOЖ) ). Vostok, Voshkod and Soyuz contained air-like mixtures at approximately 101kPa (14.7 psi). The life support system provides a nitrogen/oxygen atmosphere at sea level partial pressures. The atmosphere is then regenerated through KO2 cylinders, which absorb most of

7991-508: The background radiation from the Big Bang , is 2.7 kelvins (−270 °C; −455 °F). The plasma between galaxies is thought to account for about half of the baryonic (ordinary) matter in the universe, having a number density of less than one hydrogen atom per cubic metre and a kinetic temperature of millions of kelvins . Local concentrations of matter have condensed into stars and galaxies . Intergalactic space takes up most of

SECTION 60

#1732851337422

8122-471: The centrifugal acceleration due to the horizontal component of its velocity. For a low Earth orbit , this velocity is about 7,800 m/s (28,100 km/h; 17,400 mph); by contrast, the fastest piloted airplane speed ever achieved (excluding speeds achieved by deorbiting spacecraft) was 2,200 m/s (7,900 km/h; 4,900 mph) in 1967 by the North American X-15 . To achieve an orbit,

8253-500: The cosmic microwave background using satellites like the Wilkinson Microwave Anisotropy Probe . These observations indicate that the spatial geometry of the observable universe is " flat ", meaning that photons on parallel paths at one point remain parallel as they travel through space to the limit of the observable universe, except for local gravity. The flat universe, combined with the measured mass density of

8384-467: The immune system . Lesser symptoms include loss of body mass, nasal congestion, sleep disturbance, and puffiness of the face. During long-duration space travel, radiation can pose an acute health hazard . Exposure to high-energy, ionizing cosmic rays can result in fatigue, nausea, vomiting, as well as damage to the immune system and changes to the white blood cell count. Over longer durations, symptoms include an increased risk of cancer, plus damage to

8515-426: The zodiacal light . Interplanetary space contains the magnetic field generated by the Sun. There are magnetospheres generated by planets such as Jupiter, Saturn, Mercury and the Earth that have their own magnetic fields. These are shaped by the influence of the solar wind into the approximation of a teardrop shape, with the long tail extending outward behind the planet. These magnetic fields can trap particles from

8646-549: The CO2 and water produced by the crew biologically and regenerates the oxygen, the LiOH cylinders then absorb the leftover CO2. The Paragon Space Development Corporation is developing a plug and play ECLSS called commercial crew transport-air revitalization system (CCT-ARS) for future spacecraft partially paid for using NASA's Commercial Crew Development ( CCDev ) funding. The CCT-ARS provides seven primary spacecraft life support functions in

8777-421: The Earth's magnetosphere and the solar wind. The inner boundary is the ionosphere . The variable space-weather conditions of geospace are affected by the behavior of the Sun and the solar wind; the subject of geospace is interlinked with heliophysics —the study of the Sun and its impact on the planets of the Solar System. The day-side magnetopause is compressed by solar-wind pressure—the subsolar distance from

8908-820: The Space Shuttle, NASA includes in the ECLSS category systems that provide both life support for the crew and environmental control for payloads. The Shuttle Reference Manual contains ECLSS sections on: Crew Compartment Cabin Pressurization, Cabin Air Revitalization, Water Coolant Loop System, Active Thermal Control System, Supply and Waste Water, Waste Collection System, Waste Water Tank, Airlock Support, Extravehicular Mobility Units , Crew Altitude Protection System, and Radioisotope Thermoelectric Generator Cooling and Gaseous Nitrogen Purge for Payloads. The life-support system on

9039-452: The Sun. It is the space between the stars or stellar systems within a nebula or galaxy. Interstellar space contains an interstellar medium of sparse matter and radiation. The boundary between an astrosphere and interstellar space is known as an astropause . For the Sun, the astrosphere and astropause are called the heliosphere and heliopause. Approximately 70% of the mass of the interstellar medium consists of lone hydrogen atoms; most of

9170-446: The US), is generally not free of pathogens. World Health Organization Guidelines from 2006 offer a framework for safe reuse of waste , using a multiple barrier approach. Slow composting toilets employ a passive approach. Common applications involve modest and often seasonal use, such as remote trail networks. They are typically designed such that the materials deposited can be isolated from

9301-446: The air. Commercial systems provide ventilation that moves air from the bathroom, through the waste container, and out a vertical pipe, venting above the roof. This air movement (via convection or fan forced) passes carbon dioxide and odors. Some units require manual methods for periodic aeration of the solid mass such as rotating the composting chamber or pulling an "aerator rake" through the mass. Composting toilets convert feces into

9432-399: The atmosphere or ice deposits. All space missions to date have used supplied food. Life-support systems could include a plant cultivation system which allows food to be grown within buildings or vessels. This would also regenerate water and oxygen. However, no such system has flown in outer space as yet. Such a system could be designed so that it reuses most (otherwise lost) nutrients. This

9563-732: The atmosphere to support itself, which he calculated to be at an altitude of about 83.8 km (52.1 mi). This distinguishes altitudes below as the region of aerodynamics and airspace , and above as the space of astronautics and free space . There is no internationally recognized legal altitude limit on national airspace, although the Kármán line is the most frequently used for this purpose. Objections have been made to setting this limit too high, as it could inhibit space activities due to concerns about airspace violations. It has been argued for setting no specified singular altitude in international law, instead applying different limits depending on

9694-516: The bell are through a bell umbilical, made up from a number of hoses and electrical cables twisted together and deployed as a unit. This is extended to the divers through the diver umbilicals. The accommodation life support system maintains the chamber environment within the acceptable range for health and comfort of the occupants. Temperature, humidity, breathing gas quality sanitation systems and equipment function are monitored and controlled. Micro-Ecological Life Support System Alternative ( MELiSSA )

9825-498: The blood empties into the lungs to try to equalize the partial pressure gradient. Once the deoxygenated blood arrives at the brain, humans lose consciousness after a few seconds and die of hypoxia within minutes. Blood and other body fluids boil when the pressure drops below 6.3 kilopascals (1 psi), and this condition is called ebullism . The steam may bloat the body to twice its normal size and slow circulation, but tissues are elastic and porous enough to prevent rupture. Ebullism

9956-399: The body adjusts to the new environment. Longer-term exposure to weightlessness results in muscle atrophy and deterioration of the skeleton, or spaceflight osteopenia . These effects can be minimized through a regimen of exercise. Other effects include fluid redistribution, slowing of the cardiovascular system , decreased production of red blood cells , balance disorders, and a weakening of

10087-416: The carbon to nitrogen ratio. Alternatives with smaller composting chambers are called "self-contained composting toilets" since the composting chamber is part of the toilet unit itself. Composting toilets can be suitable in areas such as a rural area or a park that lacks a suitable water supply , sewers and sewage treatment . They can also help increase the resilience of existing sanitation systems in

10218-444: The case, in particular based on the craft and its purpose. Spacecraft have flown over foreign countries as low as 30 km (19 mi), as in the example of the Space Shuttle. The Outer Space Treaty provides the basic framework for international space law. It covers the legal use of outer space by nation states, and includes in its definition of outer space , the Moon, and other celestial bodies. The treaty states that outer space

10349-414: The center of the Earth is typically 10 Earth radii. On the night side, the solar wind stretches the magnetosphere to form a magnetotail that sometimes extends out to more than 100–200 Earth radii. For roughly four days of each month, the lunar surface is shielded from the solar wind as the Moon passes through the magnetotail. Geospace is populated by electrically charged particles at very low densities,

10480-414: The compost chamber is not safe for food production. High temperatures or long composting times are required to kill helminth eggs, the hardiest of all pathogens. Helminth infections are common in many developing countries . In thermophilic composting bacteria that thrive at temperatures of 40–60 °C (104–140 °F) oxidize (break down) waste into its components, some of which are consumed in

10611-431: The composting chamber insulated and warm protects the composting process from slowing due to low temperatures. The following gases may be emitted during the composting process that takes place in composting toilets: hydrogen sulfide (H 2 S), ammonia , nitrous oxide (N 2 O) and volatile organic compounds (VOCs). These gases can potentially lead to complaints about odours. Some methane may also be present, but it

10742-447: The continually expanding space. Matter that remained following the initial expansion has since undergone gravitational collapse to create stars, galaxies and other astronomical objects, leaving behind a deep vacuum that forms what is now called outer space. As light has a finite velocity, this theory constrains the size of the directly observable universe. The present day shape of the universe has been determined from measurements of

10873-442: The correct body temperature, an acceptable pressure on the body and deal with the body's waste products. Shielding against harmful external influences such as radiation and micro-meteorites may also be necessary. Components of the life-support system are life-critical , and are designed and constructed using safety engineering techniques. In underwater diving , the breathing apparatus is considered to be life support equipment, and

11004-406: The cosmic rays upon the shielding produces additional radiation that can affect the crew. Further research is needed to assess the radiation hazards and determine suitable countermeasures. The transition between Earth's atmosphere and outer space lacks a well-defined physical boundary, with the air pressure steadily decreasing with altitude until it mixes with the solar wind. Various definitions for

11135-404: The creation of anaerobic conditions that can result from over saturation of the compost, which leads to odors and vector problems. This usually requires all users to use the toilet in a seated position. Offering a waterless urinal in addition to the toilet can help keep excess amounts of urine out of the composting chamber. Alternatively, in rural areas, men and boys may be encouraged just to find

11266-450: The definition of outer space, the atmospheric density inside low-Earth orbital space, the first few hundred kilometers above the Kármán line, is still sufficient to produce significant drag on satellites. Geospace is a region of space that includes Earth's upper atmosphere and magnetosphere . The Van Allen radiation belts lie within the geospace. The outer boundary of geospace is the magnetopause , which forms an interface between

11397-422: The direction and speed of ions in the atmosphere were made from a sounding rocket . The altitude of 118 km (73.3 mi) above Earth was the midpoint for charged particles transitioning from the gentle winds of the Earth's atmosphere to the more extreme flows of outer space. The latter can reach velocities well over 268 m/s (880 ft/s). Spacecraft have entered into a highly elliptical orbit with

11528-452: The drafting of UN resolutions for the peaceful uses of outer space, anti-satellite weapons have been tested in Earth orbit . The concept that the space between the Earth and the Moon must be a vacuum was first proposed in the 17th century after scientists discovered that air pressure decreased with altitude. The immense scale of outer space was grasped in the 20th century when the distance to

11659-502: The effects of Coriolis force (a force imparted at right angles to motion within the cabin) must be dealt with. And there is concern that rotation could aggravate the effects of vestibular disruption. American Mercury, Gemini and Apollo spacecraft contained 100% oxygen atmospheres, suitable for short duration missions, to minimize weight and complexity. The Space Shuttle was the first American spacecraft to have an Earth-like atmospheric mixture, comprising 22% oxygen and 78% nitrogen. For

11790-400: The entire compost heap reaches a temperature of 62 °C (144 °F) for one hour, 50 °C (122 °F) for one day, 46 °C (115 °F) for one week or 43 °C (109 °F) for one month, although others regard this as overly optimistic. Four main factors affect the decomposition process: Human waste and food waste do not provide optimum conditions for composting. Usually

11921-500: The environmental control and life-support system (ECLSS)" for Sundancer has begun. Natural LSS like the Biosphere 2 in Arizona have been tested for future space travel or colonization. These systems are also known as closed ecological systems . They have the advantage of using solar energy as primary energy only and being independent from logistical support with fuel. Natural systems have

12052-436: The eyes, nervous system , lungs and the gastrointestinal tract . On a round-trip Mars mission lasting three years, a large fraction of the cells in an astronaut's body would be traversed and potentially damaged by high energy nuclei. The energy of such particles is significantly diminished by the shielding provided by the walls of a spacecraft and can be further diminished by water containers and other barriers. The impact of

12183-523: The face of possible natural disasters such as climate change , earthquakes or tsunami . Composting toilets can reduce or perhaps eliminate the need for a septic tank system to reduce environmental footprint (particularly when used in conjunction with an on-site greywater treatment system ). These types of toilets can be used for resource recovery by reusing sanitized feces and urine as fertilizer and soil conditioner for gardening or ornamental activities. A composting toilet consists of two elements:

12314-418: The function of the equipment. In human spaceflight , a life-support system is a group of devices that allow a human being to survive in outer space. US government space agency NASA , and private spaceflight companies use the phrase "environmental control and life-support system" or the acronym ECLSS when describing these systems. The life-support system may supply air, water and food. It must also maintain

12445-479: The harsh environment, several life forms have been found that can withstand extreme space conditions for extended periods. Species of lichen carried on the ESA BIOPAN facility survived exposure for ten days in 2007. Seeds of Arabidopsis thaliana and Nicotiana tabacum germinated after being exposed to space for 1.5 years. A strain of Bacillus subtilis has survived 559 days when exposed to low Earth orbit or

12576-596: The high energy range, the flux of electrons is only about 1% of that of protons. Cosmic rays can damage electronic components and pose a health threat to space travelers. Smells produced returning from low Earth orbit extravehicular activity have a burned/metallic odor, similar to the scent of arc welding fumes, resulting from oxygen in low Earth orbit around the ISS, which clings to suits and equipment. Other regions of space could have very different smells, like that of different alcohols in molecular clouds . Despite

12707-486: The highest degree of efficiency due to integration of multiple functions. They also provide the proper ambience for humans which is necessary for a longer stay in outer space. Underwater habitats and surface saturation accommodation facilities provide life-support for their occupants over periods of days to weeks. The occupants are constrained from immediate return to surface atmospheric pressure by decompression obligations of up to several weeks. The life support system of

12838-420: The human body. Medications that are lipophilic (dissolved in fats) are more likely to reach groundwater by leaching from fecal wastes. Sewage treatment plants remove an average of 60% of these medications. The percentage of medications degraded during composting of waste has not yet been reported. In the late 19th century in developed countries, some inventors, scientists and public health officials supported

12969-610: The international co-operation in the peaceful uses of outer space and preventing an arms race in space. Four additional space law treaties have been negotiated and drafted by the UN's Committee on the Peaceful Uses of Outer Space . Still, there remains no legal prohibition against deploying conventional weapons in space, and anti-satellite weapons have been successfully tested by the USA, USSR, China, and in 2019, India. The 1979 Moon Treaty turned

13100-399: The interstellar medium, including the heavy elements previously formed within the star's core. The density of matter in the interstellar medium can vary considerably: the average is around 10 particles per m , but cold molecular clouds can hold 10 –10 per m . Composting toilet In many composting toilet designs, a carbon additive such as sawdust , coconut coir , or peat moss

13231-588: The jurisdiction of all heavenly bodies (including the orbits around such bodies) over to the international community. The treaty has not been ratified by any nation that currently practices human spaceflight. In 1976, eight equatorial states (Ecuador, Colombia, Brazil, The Republic of the Congo, Zaire, Uganda, Kenya, and Indonesia) met in Bogotá, Colombia: with their "Declaration of the First Meeting of Equatorial Countries", or

13362-442: The large pressure differential between inside and outside the chest. Even if the subject's airway is fully open, the flow of air through the windpipe may be too slow to prevent the rupture. Rapid decompression can rupture eardrums and sinuses, bruising and blood seep can occur in soft tissues, and shock can cause an increase in oxygen consumption that leads to hypoxia . As a consequence of rapid decompression, oxygen dissolved in

13493-416: The length of the mission, astronauts may need artificial gravity to reduce the effects of space adaptation syndrome , body fluid redistribution, and loss of bone and muscle mass. Two methods of generating artificial weight in outer space exist. If a spacecraft's engines could produce thrust continuously on the outbound trip with a thrust level equal to the mass of the ship, it would continuously accelerate at

13624-404: The magnetic field and particle flux from the Sun. The distance and strength of the heliopause varies depending on the activity level of the solar wind. The heliopause in turn deflects away low-energy galactic cosmic rays, with this modulation effect peaking during solar maximum. The volume of interplanetary space is a nearly total vacuum, with a mean free path of about one astronomical unit at

13755-411: The material may become too compact and form impermeable layers, which leads to anaerobic conditions and odour. Leachate removal controls moisture levels, which is necessary to ensure rapid, aerobic composting. Some commercial units include a urine-separator or urine-diverting system and/or a drain at the bottom of the composter for this purpose. Microbial action also requires oxygen, typically from

13886-413: The more immediate effect that the metabolic parameters have. Outer space life-support systems maintain atmospheres composed, at a minimum, of oxygen, water vapor and carbon dioxide. The partial pressure of each component gas adds to the overall barometric pressure . However, the elimination of diluent gases substantially increases fire risks, especially in ground operations when for structural reasons

14017-518: The most distant high-z sources, indicating the presence of magnetic fields. Outside a protective atmosphere and magnetic field, there are few obstacles to the passage through space of energetic subatomic particles known as cosmic rays. These particles have energies ranging from about 10   eV up to an extreme 10  eV of ultra-high-energy cosmic rays . The peak flux of cosmic rays occurs at energies of about 10  eV, with approximately 87% protons, 12% helium nuclei and 1% heavier nuclei. In

14148-525: The motions of which are controlled by the Earth's magnetic field . These plasmas form a medium from which storm-like disturbances powered by the solar wind can drive electrical currents into the Earth's upper atmosphere. Geomagnetic storms can disturb two regions of geospace, the radiation belts and the ionosphere. These storms increase fluxes of energetic electrons that can permanently damage satellite electronics, interfering with shortwave radio communication and GPS location and timing. Magnetic storms can be

14279-448: The occupants free access to the ambient environment within a specific depth range, while saturation divers accommodated in surface systems are transferred under pressure to the working depth in a closed diving bell The life support system for the bell provides and monitors the main supply of breathing gas , and the control station monitors the deployment and communications with the divers. Primary gas supply, power and communications to

14410-467: The operational part. The toilet can also be closed to allow further mesophilic composting. Slow composting toilets rely on long retention times for pathogen reduction and for decomposition of waste or on the combination of time and/or the addition of red wiggler worms for vermi-composting. Worms can be introduced to accelerate composting. Some jurisdictions of the US consider these worms as invasive species . "Self-contained" composting toilets compost in

14541-403: The orbital distance of the Earth. This space is not completely empty, and is sparsely filled with cosmic rays, which include ionized atomic nuclei and various subatomic particles. There is gas, plasma and dust, small meteors , and several dozen types of organic molecules discovered to date by microwave spectroscopy . A cloud of interplanetary dust is visible at night as a faint band called

14672-571: The process, reducing volume and eliminating potential pathogens . To destroy pathogens, thermophilic composting must heat the compost pile sufficiently, or enough time (1–2 years) must elapse since fresh material was added that biological activity has had the same pathogen removal effect. One guideline claims that pathogen levels are reduced to a safe level by thermophilic composting at temperatures of 55 °C for at least two weeks or at 60 °C for one week. An alternative guideline claims that complete pathogen destruction may be achieved already if

14803-429: The rate of 32.2 feet per second (9.8 m/s) per second, and the crew would experience a pull toward the ship's aft bulkhead at normal Earth gravity (one g). The effect is proportional to the rate of acceleration. When the ship reaches the halfway point, it would turn around and produce thrust in the retrograde direction to slow down. Alternatively, if the ship's cabin is designed with a large cylindrical wall, or with

14934-439: The remainder consists of helium atoms. This is enriched with trace amounts of heavier atoms formed through stellar nucleosynthesis . These atoms are ejected into the interstellar medium by stellar winds or when evolved stars begin to shed their outer envelopes such as during the formation of a planetary nebula . The cataclysmic explosion of a supernova propagates shock waves of stellar ejecta outward, distributing it throughout

15065-598: The risk of pathogens. Waste-derived compost may contain prescription pharmaceuticals . Such residues are also present in conventional sewage treatment effluent. This could contaminate groundwater . Among the medications that have been found in groundwater in recent years are antibiotics , antidepressants , blood thinners , ACE inhibitors , calcium-channel blockers , digoxin , estrogen , progesterone , testosterone , Ibuprofen , caffeine , carbamazepine , fibrates and cholesterol -reducing medications. Between 30% and 95% of pharmaceuticals medications are excreted by

15196-640: The same as the partial pressure of oxygen at the Earth's surface. This pressure is high enough to prevent ebullism, but evaporation of nitrogen dissolved in the blood could still cause decompression sickness and gas embolisms if not managed. Humans evolved for life in Earth gravity , and exposure to weightlessness has been shown to have deleterious effects on human health. Initially, more than 50% of astronauts experience space motion sickness . This can cause nausea and vomiting, vertigo , headaches, lethargy , and overall malaise. The duration of space sickness varies, but it typically lasts for 1–3 days, after which

15327-432: The secondary composting step, produce a humus -like end product that can be used to enrich soil if local regulations allow this. Some composting toilets have urine diversion systems in the toilet bowl to collect the urine separately and control excess moisture. A vermifilter toilet is a composting toilet with flushing water where earthworms are used to promote decomposition to compost. Composting toilets do not require

15458-468: The solar wind and other sources, creating belts of charged particles such as the Van Allen radiation belts. Planets without magnetic fields, such as Mars, have their atmospheres gradually eroded by the solar wind. Interstellar space is the physical space outside of the bubbles of plasma known as astrospheres , formed by stellar winds originating from individual stars, or formed by solar wind emanating from

15589-625: The space around just about every class of celestial object. Star formation in spiral galaxies can generate small-scale dynamos , creating turbulent magnetic field strengths of around 5–10 μ G . The Davis–Greenstein effect causes elongated dust grains to align themselves with a galaxy's magnetic field, resulting in weak optical polarization . This has been used to show ordered magnetic fields that exist in several nearby galaxies. Magneto-hydrodynamic processes in active elliptical galaxies produce their characteristic jets and radio lobes . Non-thermal radio sources have been detected even among

15720-409: The starting point of deep-space from, "That which lies beyond the orbit of the moon," to "That which lies beyond the farthest reaches of the Solar System itself." The International Telecommunication Union responsible for radio communication , including with satellites, defines deep-space as, "distances from the Earth equal to, or greater than, 2 million km (1.2 million mi)," which

15851-422: The surface of the filter bed while liquid drains through the filter medium and is discharged from the reactor. The solids (feces and toilet paper) are aerobically digested by aerobic bacteria and composting earthworms into castings (humus), thereby significantly reducing the volume of organic material. Some units employ roll-away containers fitted with aerators, while others use sloped-bottom tanks. Maintenance

15982-407: The throat and lungs boil away. More specifically, exposed bodily liquids such as saliva, tears, and liquids in the lungs boil away. Hence, at this altitude, human survival requires a pressure suit, or a pressurized capsule. Out in space, sudden exposure of an unprotected human to very low pressure , such as during a rapid decompression, can cause pulmonary barotrauma —a rupture of the lungs, due to

16113-433: The total cabin pressure must exceed the external atmospheric pressure; see Apollo 1 . Furthermore, oxygen toxicity becomes a factor at high oxygen concentrations. For this reason, most modern crewed spacecraft use conventional air (nitrogen/oxygen) atmospheres and use pure oxygen only in pressure suits during extravehicular activity where acceptable suit flexibility mandates the lowest inflation pressure possible. Water

16244-427: The universe and the accelerating expansion of the universe , indicates that space has a non-zero vacuum energy , which is called dark energy . Estimates put the average energy density of the present day universe at the equivalent of 5.9 protons per cubic meter, including dark energy, dark matter, and baryonic matter (ordinary matter composed of atoms). The atoms account for only 4.6% of the total energy density, or

16375-501: The use of "dry earth closets", a type of dry toilet with similarities to composting toilets, although the collection vessel for the human waste was not designed to compost. In 2016, the International Organization for Standardization ( ISO ) published the standard "Activities relating to drinking water and wastewater services — Guidelines for the management of basic on-site domestic wastewater services". The standard

16506-478: The use of full term "outer space", with the earliest recorded use of this meaning in an epic poem by John Milton called Paradise Lost , published in 1667. The term outward space existed in a poem from 1842 by the English poet Lady Emmeline Stuart-Wortley called "The Maiden of Moscow", but in astronomy the term outer space found its application for the first time in 1845 by Alexander von Humboldt . The term

16637-512: The user than the "drop and forget" approach of pit latrines. Unlike flush toilets , composting toilets do not require a sewerage system and do not mix flushing water with urine and feces. They require more involvement by the user than the "flush and forget" approach of flush toilets connected to sewage treatment plants . Composting toilets, although similar to and sharing many advantages and disadvantages with urine-diverting dry toilets (UDDT), are more complex and require more maintenance to keep

16768-399: The volume of the universe , but even galaxies and star systems consist almost entirely of empty space. Most of the remaining mass-energy in the observable universe is made up of an unknown form, dubbed dark matter and dark energy . Outer space does not begin at a definite altitude above Earth's surface. The Kármán line , an altitude of 100 km (62 mi) above sea level ,

16899-406: The water and nitrogen content is too high, particularly when urine is mixed with feces. Additives or "bulking material", such as wood chips, bark chips, sawdust, shredded dry leaves, ash and pieces of paper can absorb moisture. The additives improve pile aeration and increase the carbon to nitrogen ratio. Bulking material also covers feces and reduces insect access. Absent sufficient bulking material,

17030-457: Was eventually popularized through the writings of H. G. Wells after 1901. Theodore von Kármán used the term of free space to name the space of altitudes above Earth where spacecrafts reach conditions sufficiently free from atmospheric drag, differentiating it from airspace , identifying a legal space above territories free from the sovereign jurisdiction of countries. " Spaceborne " denotes existing in outer space, especially if carried by

17161-647: Was passed by the United Nations General Assembly in 1963 and signed in 1967 by the Union of Soviet Socialist Republics (USSR), the United States of America (USA), and the United Kingdom (UK). As of 2017, 105 state parties have either ratified or acceded to the treaty. An additional 25 states signed the treaty, without ratifying it. Since 1958, outer space has been the subject of multiple United Nations resolutions. Of these, more than 50 have been concerning

#421578