{"id":130,"date":"2024-05-29T10:00:52","date_gmt":"2024-05-29T07:00:52","guid":{"rendered":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/?page_id=130"},"modified":"2024-06-11T04:35:51","modified_gmt":"2024-06-11T01:35:51","slug":"on-board-systems","status":"publish","type":"page","link":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/on-board-systems\/","title":{"rendered":"On Board systems of the ISS"},"content":{"rendered":"\n<div class=\"wp-block-group alignwide has-text-color has-link-color wp-elements-62ae644dd1bc806ec2cd0072f34d3dac is-content-justification-space-between is-layout-flex wp-container-core-group-is-layout-4 wp-block-group-is-layout-flex\" style=\"color:#ffffff;padding-right:var(--wp--preset--spacing--30);padding-left:var(--wp--preset--spacing--30)\">\n<div class=\"wp-block-group is-layout-flex wp-container-core-group-is-layout-2 wp-block-group-is-layout-flex\"><div class=\"wp-block-site-logo\"><a href=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/\" class=\"custom-logo-link\" rel=\"home\"><img loading=\"lazy\" decoding=\"async\" width=\"60\" height=\"60\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/05\/ISS_emblem.png\" class=\"custom-logo\" alt=\"International Space Station\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/05\/ISS_emblem.png 1891w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/05\/ISS_emblem-300x300.png 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/05\/ISS_emblem-1024x1024.png 1024w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/05\/ISS_emblem-150x150.png 150w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/05\/ISS_emblem-768x768.png 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/05\/ISS_emblem-1536x1536.png 1536w\" sizes=\"auto, (max-width: 60px) 100vw, 60px\" \/><\/a><\/div>\n\n\n<div class=\"wp-block-group is-layout-flow wp-container-core-group-is-layout-1 wp-block-group-is-layout-flow\"><p class=\"wp-block-site-title\"><a href=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\" target=\"_self\" rel=\"home\">International Space Station<\/a><\/p><\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group wp-elements-7d4a3dc398bda278f48df7abb54917f8 is-content-justification-left is-layout-flex wp-container-core-group-is-layout-3 wp-block-group-is-layout-flex\"><nav class=\"is-responsive items-justified-right wp-block-navigation is-horizontal is-content-justification-right is-layout-flex wp-container-core-navigation-is-layout-1 wp-block-navigation-is-layout-flex\" aria-label=\"\u03a0\u03bb\u03bf\u03ae\u03b3\u03b7\u03c3\u03b7\" \n\t\t data-wp-interactive=\"core\/navigation\" data-wp-context='{\"overlayOpenedBy\":{\"click\":false,\"hover\":false,\"focus\":false},\"type\":\"overlay\",\"roleAttribute\":\"\",\"ariaLabel\":\"\\u039c\\u03b5\\u03bd\\u03bf\\u03cd\"}'><button aria-haspopup=\"dialog\" 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class=\"wp-block-navigation__container is-responsive items-justified-right wp-block-navigation\"><li class=\"wp-block-navigation-item wp-block-navigation-link\"><a class=\"wp-block-navigation-item__content\"  href=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/\"><span class=\"wp-block-navigation-item__label\">Home<\/span><\/a><\/li><li class=\"wp-block-navigation-item wp-block-navigation-link\"><a class=\"wp-block-navigation-item__content\"  href=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/history\/\"><span class=\"wp-block-navigation-item__label\">History<\/span><\/a><\/li><li class=\"wp-block-navigation-item wp-block-navigation-link\"><a class=\"wp-block-navigation-item__content\"  href=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/structure\/\"><span class=\"wp-block-navigation-item__label\">Structure<\/span><\/a><\/li><li class=\"wp-block-navigation-item wp-block-navigation-link\"><a class=\"wp-block-navigation-item__content\"  href=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/On%20Board%20Systems\/\"><span class=\"wp-block-navigation-item__label\">On Board Systems<\/span><\/a><\/li><li class=\"wp-block-navigation-item wp-block-navigation-link\"><a class=\"wp-block-navigation-item__content\"  href=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/space-stations\/\"><span class=\"wp-block-navigation-item__label\">Space Stations<\/span><\/a><\/li><li class=\"wp-block-navigation-item wp-block-navigation-link\"><a class=\"wp-block-navigation-item__content\"  href=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/form\/\"><span class=\"wp-block-navigation-item__label\">Questionnaire<\/span><\/a><\/li><\/ul>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div><\/nav><\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading animated slideInDown fast has-body-font-family has-x-large-font-size\">On Board systems of the ISS<\/h2>\n\n\n\n<blockquote class=\"wp-block-quote is-style-plain is-layout-flow wp-block-quote-is-layout-flow is-style-plain--023963a9b88c4977c1a20daea642516d\" style=\"font-size:clamp(0.875rem, 0.875rem + ((1vw - 0.2rem) * 1), 1.22rem);\">\n<p class=\"o-typing-delay-200ms o-typing-faster animated zoomIn fast wp-block-paragraph\"><strong><o-anim-typing>the systems that act as the stations life support <\/o-anim-typing><\/strong><\/p>\n<\/blockquote>\n\n\n\n<div class=\"wp-block-group alignfull has-base-background-color has-background is-nowrap is-layout-flex wp-container-core-group-is-layout-7 wp-block-group-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--50);padding-right:var(--wp--preset--spacing--50);padding-bottom:var(--wp--preset--spacing--50);padding-left:var(--wp--preset--spacing--50)\">\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-1 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-vertically-aligned-stretch is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<div class=\"wp-block-group is-vertical is-content-justification-stretch is-layout-flex wp-container-core-group-is-layout-6 wp-block-group-is-layout-flex\" style=\"min-height:100%\">\n<p class=\"animated slideInLeft wp-block-paragraph\">The critical systems that are the sole reason as to why life is even allowed to exist in the ISS make up the <strong>Environmental Control and Life Support System<\/strong>&nbsp;(<strong>ECLSS<\/strong>) and include the atmosphere control system that provides or controls&nbsp;atmospheric pressure and oxygen levels, the electrical power and thermal control system, the water supply system and the communication and computers systems as well as systems for fire detection and suppression along with waste management . The highest priority for the ECLSS is the ISS atmosphere, but the system also collects, processes, and stores both waste and water produced and used by the crew\u2014a process that recycles fluid from the sink, shower, toilet, and condensation from the air.<\/p>\n\n\n\n<p class=\"animated slideInLeft fast has-body-font-family wp-block-paragraph\" style=\"font-size:clamp(1.182rem, 1.182rem + ((1vw - 0.2rem) * 1), 1.87rem);line-height:1.6\"><\/p>\n\n\n\n<div class=\"wp-block-group has-global-padding is-content-justification-left is-layout-constrained wp-container-core-group-is-layout-5 wp-block-group-is-layout-constrained\"><\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<figure class=\"wp-block-image size-large is-resized is-style-rounded animated slideInRight fast is-style-rounded--351fa2b1ed68636ab6c16110abcfc1dc\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"682\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/atmospheric-ppl-1024x682.jpg\" alt=\"\" class=\"wp-image-262\" style=\"width:541px;height:auto\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/atmospheric-ppl-1024x682.jpg 1024w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/atmospheric-ppl-300x200.jpg 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/atmospheric-ppl-768x511.jpg 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/atmospheric-ppl.jpg 1280w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Scott Kelly and&nbsp;Terry Virts inspect the Carbon Dioxide Removal Assembly on the ISS&nbsp;(NASA, Wikimedia Commons)<\/figcaption><\/figure>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull animated slideInUp o-anim-offset-100px has-accent-background-color has-background has-global-padding is-layout-constrained wp-container-core-group-is-layout-9 wp-block-group-is-layout-constrained\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--10);padding-right:var(--wp--preset--spacing--10);padding-bottom:0;padding-left:var(--wp--preset--spacing--10)\">\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-3 wp-block-columns-is-layout-flex\" style=\"padding-top:var(--wp--preset--spacing--20);padding-bottom:var(--wp--preset--spacing--30)\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full animated slideInLeft\"><img loading=\"lazy\" decoding=\"async\" width=\"720\" height=\"425\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/720px-SpaceStationCycle.svg_-1.png\" alt=\"\" class=\"wp-image-364\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/720px-SpaceStationCycle.svg_-1.png 720w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/720px-SpaceStationCycle.svg_-1-300x177.png 300w\" sizes=\"auto, (max-width: 720px) 100vw, 720px\" \/><\/figure>\n\n\n\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\">\n<figure class=\"wp-block-table animated slideInUp has-medium-font-size\"><table class=\"has-accent-background-color has-background has-fixed-layout\" style=\"border-style:none;border-width:0px\"><tbody><tr><td><\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">The interactions between the components of the ISS Environmental Control and Life Support System (ECLSS)<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-container-core-column-is-layout-5 wp-block-column-is-layout-flow\" style=\"flex-basis:60%\">\n<p class=\"animated slideInUp o-anim-offset-100px has-body-font-family has-xx-large-font-size wp-block-paragraph\" style=\"line-height:1.2\">The atmosphere control systems<\/p>\n\n\n\n<div class=\"wp-block-columns animated slideInUp is-layout-flex wp-container-core-columns-is-layout-2 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"has-body-font-family has-large-font-size wp-container-content-3 wp-block-paragraph\" style=\"line-height:1.7;text-decoration:underline\"><strong>Air revitalization system<\/strong> <\/p>\n\n\n\n<p class=\"has-body-font-family has-medium-font-size wp-container-content-4 wp-block-paragraph\" style=\"line-height:1.7\">The Air Revitalization System removes carbon dioxide, controls trace contaminants and monitors the major constituents in the cabin atmosphere. Crew-generated carbon dioxide is removed from the atmosphere by sorbent beds (Carbon Dioxide Removal Assembly (CDRA)). The beds are regenerated upon exposure to heat and space vacuum. A Trace Contaminant Control System(TCCS) ensures that over 200 various trace chemical contaminants generated from material off-gassing and crew metabolic functions remain within allowable limits. A mass spectrometer (MCA) measures the oxygen, nitrogen, hydrogen, carbon dioxide, methane and water vapour content of the cabin atmosphere. This NASA rack is placed in&nbsp;<em>Tranquility<\/em> and was flown to the station aboard&nbsp;STS-128&nbsp;and temporarily installed in the&nbsp;Japanese Experiment Module&nbsp;pressurised module during Space Shuttle&nbsp;<em>Endeavour<\/em>&nbsp;mission&nbsp;STS-130.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull animated slideInUp has-background has-global-padding is-layout-constrained wp-container-core-group-is-layout-10 wp-block-group-is-layout-constrained\" style=\"background-color:#914e06;margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--50);padding-right:var(--wp--preset--spacing--50);padding-bottom:var(--wp--preset--spacing--50);padding-left:var(--wp--preset--spacing--50)\">\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-5 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column has-global-padding is-content-justification-left is-layout-constrained wp-container-core-column-is-layout-6 wp-block-column-is-layout-constrained\" style=\"flex-basis:40%\">\n<figure class=\"wp-block-image size-large animated slideInUp\"><img loading=\"lazy\" decoding=\"async\" width=\"653\" height=\"1024\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Mockup_of_the_Oxygen_Generation_System_Rack_pillars-2-653x1024.jpg\" alt=\"\" class=\"wp-image-287\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Mockup_of_the_Oxygen_Generation_System_Rack_pillars-2-653x1024.jpg 653w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Mockup_of_the_Oxygen_Generation_System_Rack_pillars-2-191x300.jpg 191w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Mockup_of_the_Oxygen_Generation_System_Rack_pillars-2-768x1205.jpg 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Mockup_of_the_Oxygen_Generation_System_Rack_pillars-2-979x1536.jpg 979w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Mockup_of_the_Oxygen_Generation_System_Rack_pillars-2-1305x2048.jpg 1305w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Mockup_of_the_Oxygen_Generation_System_Rack_pillars-2-scaled.jpg 1632w\" sizes=\"auto, (max-width: 653px) 100vw, 653px\" \/><figcaption class=\"wp-element-caption\">International Space Station (ISS) Environmental Control And Life Support Systems-ECLSS Racks In BLDG 4755\/MOCKUP. Views Oxygen Generation System (OGS) Rak<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-container-core-column-is-layout-9 wp-block-column-is-layout-flow\" style=\"flex-basis:60%\">\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-4 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"animated slideInUp has-body-font-family wp-container-content-5 wp-block-paragraph\" style=\"font-size:clamp(1.255rem, 1.255rem + ((1vw - 0.2rem) * 1), 2.01rem);text-decoration:underline\"><strong>Oxygen Generating System<\/strong><\/p>\n\n\n\n<p class=\"animated slideInUp wp-container-content-6 wp-block-paragraph\">The Oxygen Generating System (OGS) is a NASA rack designed to electrolyse water from the Water Recovery System to produce oxygen and hydrogen. The oxygen is delivered to the cabin atmosphere. The unit is installed in the&nbsp;<em>Destiny<\/em>&nbsp;module. During one of the&nbsp;spacewalks&nbsp;conducted by&nbsp;STS-117&nbsp;astronauts, a hydrogen vent valve required to begin using the system was installed. The system was delivered in 2006 by&nbsp;STS-121, and became operational on 12 July 2007.The Oxygen Generation System is designed to generate oxygen at a selectable rate and is capable of operating both continuously and cyclically. It provides up to 9 kg of oxygen per day during continuous operation and a normal rate of about 5.5 kg of oxygen per day during cyclic operation.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"animated slideInUp has-body-font-family has-large-font-size wp-block-paragraph\" style=\"text-decoration:underline\"><strong>Sabatier System <\/strong>  <\/p>\n\n\n\n<p class=\"animated slideInUp wp-block-paragraph\">The NASA Sabatier system, since 2010, closes the oxygen loop in the ECLSS by combining waste hydrogen from the Oxygen generating system and carbon dioxide from the station atmosphere using the&nbsp;Sabatier reaction&nbsp;to reuse the oxygen. The outputs of this reaction are water, and methane. The water is recycled to reduce the total amount of water that must be carried to the station from Earth, and the methane is vented overboard by the now shared hydrogen vent line installed for the Oxygen generating system. Prior to the activation of the Sabatier System in October 2010 hydrogen and carbon dioxide extracted from the cabin was vented overboard.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull animated slideInUp has-base-background-color has-background has-global-padding is-layout-constrained wp-container-core-group-is-layout-13 wp-block-group-is-layout-constrained\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--50);padding-right:var(--wp--preset--spacing--50);padding-bottom:var(--wp--preset--spacing--50);padding-left:var(--wp--preset--spacing--50)\">\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-6 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<figure class=\"wp-block-image size-full is-resized is-style-rounded animated slideInLeft is-style-rounded--179ee73b7dcd848232e0b35b40eb41ef\"><img loading=\"lazy\" decoding=\"async\" width=\"450\" height=\"299\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/450px-8_July_2011_Elektron-1.jpg\" alt=\"\" class=\"wp-image-430\" style=\"aspect-ratio:4\/3;object-fit:cover;width:358px;height:auto\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/450px-8_July_2011_Elektron-1.jpg 450w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/450px-8_July_2011_Elektron-1-300x199.jpg 300w\" sizes=\"auto, (max-width: 450px) 100vw, 450px\" \/><figcaption class=\"wp-element-caption\">Elektron units in the Zvezda service module.<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full is-resized is-style-rounded animated slideInLeft is-style-rounded--410a3980fbfa1d19057ff870bc6f0884\"><img loading=\"lazy\" decoding=\"async\" width=\"1280\" height=\"848\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS-04_Yury_I._Onufrienko_performs_maintenance_on_the_Elektron_Oxygen_Generator-2.jpg\" alt=\"\" class=\"wp-image-518\" style=\"width:332px;height:auto\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS-04_Yury_I._Onufrienko_performs_maintenance_on_the_Elektron_Oxygen_Generator-2.jpg 1280w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS-04_Yury_I._Onufrienko_performs_maintenance_on_the_Elektron_Oxygen_Generator-2-300x199.jpg 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS-04_Yury_I._Onufrienko_performs_maintenance_on_the_Elektron_Oxygen_Generator-2-1024x678.jpg 1024w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS-04_Yury_I._Onufrienko_performs_maintenance_on_the_Elektron_Oxygen_Generator-2-768x509.jpg 768w\" sizes=\"auto, (max-width: 1280px) 100vw, 1280px\" \/><figcaption class=\"wp-element-caption\">Cosmonaut Yury I. Onufrienko, Expedition Four mission commander, performs maintenance on the Elektron Oxygen Generator in the Zvezda Service Module on the International Space Station (ISS).&nbsp;<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-stretch animated slideInUp is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<h2 class=\"wp-block-heading has-body-font-family has-x-large-font-size\" style=\"text-decoration:underline\"><strong>Elektron<\/strong><\/h2>\n\n\n\n<p class=\"has-body-font-family has-medium-font-size wp-block-paragraph\" style=\"line-height:1.7\">Elektron is a Russian Electrolytic Oxygen Generator, which was also used on&nbsp;Mir. It is the<strong> primary supply of oxygen <\/strong>and uses&nbsp;electrolysis&nbsp;to produce it. This process splits water molecules reclaimed from other uses on board the station into oxygen and hydrogen, then the oxygen is vented into the cabin and the hydrogen is vented into space. The three Russian Elektron oxygen generators on board the International Space Station have been plagued with problems, frequently forcing the crew to use backup sources (either bottled oxygen or the Vika system discussed below). To support the crew, NASA added the oxygen generating system discussed above. The 1&nbsp;kW (1.3&nbsp;hp) system uses approximately one litre of water per crew member per day. This water is either brought from Earth or recycled from other systems.&nbsp;<em>Mir<\/em>&nbsp;was the first spacecraft to use recycled water for oxygen production.<\/p>\n\n\n\n<p class=\"has-body-font-family has-medium-font-size wp-block-paragraph\" style=\"line-height:1.5\"><\/p>\n\n\n\n<div class=\"wp-block-group is-vertical is-content-justification-stretch is-layout-flex wp-container-core-group-is-layout-12 wp-block-group-is-layout-flex\" style=\"min-height:100%\">\n<div class=\"wp-block-group has-global-padding is-content-justification-left is-layout-constrained wp-container-core-group-is-layout-11 wp-block-group-is-layout-constrained\"><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull has-accent-background-color has-background has-global-padding is-layout-constrained wp-container-core-group-is-layout-17 wp-block-group-is-layout-constrained\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--50);padding-right:var(--wp--preset--spacing--50);padding-bottom:var(--wp--preset--spacing--50);padding-left:var(--wp--preset--spacing--50)\">\n<div style=\"height:var(--wp--preset--spacing--30)\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-7 wp-block-columns-is-layout-flex\" style=\"padding-right:0;padding-left:0\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div class=\"wp-block-group is-vertical is-content-justification-center is-nowrap is-layout-flex wp-container-core-group-is-layout-14 wp-block-group-is-layout-flex\">\n<p class=\"animated slideInUp has-body-font-family has-large-font-size wp-block-paragraph\" style=\"text-decoration:underline\"><strong>Vika<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"animated slideInUp has-medium-font-size wp-block-paragraph\" style=\"line-height:1.9\">The<strong> secondary oxygen supply<\/strong> is provided by burning oxygen-producing&nbsp;Vika&nbsp;cartridges, also known as Solid Fuel Oxygen Generation (SFOG) . Each &#8216;candle'(canisters of solid&nbsp;lithium perchlorate) takes 5\u201320 minutes to decompose at 450\u2013500&nbsp;\u00b0C (842\u2013932&nbsp;\u00b0F), producing 600 litres (130&nbsp;imp&nbsp;gal; 160&nbsp;US&nbsp;gal) of&nbsp;O<sub>2<\/sub>. Each canister can supply the oxygen needs of one crewmember for one day. This unit is manually operated. It was originally developed by &nbsp;Roscosmos&nbsp;for&nbsp;Mir.<\/p>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div class=\"wp-block-group is-vertical is-content-justification-center is-nowrap is-layout-flex wp-container-core-group-is-layout-15 wp-block-group-is-layout-flex\">\n<p class=\"animated slideInUp has-body-font-family has-large-font-size wp-block-paragraph\" style=\"text-decoration:underline\"><strong>Vozdukh<\/strong><\/p>\n\n\n\n<p class=\"animated slideInUp wp-block-paragraph\">Another Russian system, Vozdukh (Russian&nbsp;<em>\u0412\u043e\u0437\u0434\u0443\u0445<\/em>, meaning &#8220;air&#8221;), removes carbon dioxide from the air based on the use of regenerable absorbers of carbon dioxide gas.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<figure class=\"wp-block-image size-full animated slideInUp\"><img loading=\"lazy\" decoding=\"async\" width=\"2560\" height=\"1743\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss011e13009-scaled.jpg\" alt=\"\" class=\"wp-image-865\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss011e13009-scaled.jpg 2560w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss011e13009-300x204.jpg 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss011e13009-1024x697.jpg 1024w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss011e13009-768x523.jpg 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss011e13009-1536x1046.jpg 1536w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss011e13009-2048x1394.jpg 2048w\" sizes=\"auto, (max-width: 2560px) 100vw, 2560px\" \/><figcaption class=\"wp-element-caption\"><em>Cosmonaut Sergei K. Krikalev works with the European Space Agency Matroshka radiation experiment in the Zvezda service module of the International Space Station. In the upper right of the foreground is the TGK backup oxygen system, with the ceramic mitigation screen in place.<\/em><\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div class=\"wp-block-group is-vertical is-content-justification-center is-nowrap is-layout-flex wp-container-core-group-is-layout-16 wp-block-group-is-layout-flex\">\n<p class=\"animated slideInUp has-large-font-size wp-block-paragraph\" style=\"text-decoration:underline\"><strong>chemical oxygen generato<\/strong>r  <\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"animated slideInUp wp-block-paragraph\">is a device that releases&nbsp;oxygen&nbsp;via a&nbsp;chemical reaction. The oxygen source is usually an inorganic&nbsp;superoxide,&nbsp;chlorate, or&nbsp;perchlorate.&nbsp;Ozonides&nbsp;are a promising group of oxygen sources, as well. The generators are usually ignited by a&nbsp;firing pin, and the chemical reaction is usually&nbsp;exothermic, making the generator a potential&nbsp;fire hazard.&nbsp;Potassium superoxide&nbsp;was used as an oxygen source on early crewed missions of the&nbsp;Soviet space program, in&nbsp;submarines&nbsp;for use in emergency situations, for&nbsp;firefighters, and for&nbsp;mine rescue.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull has-global-padding is-layout-constrained wp-container-core-group-is-layout-23 wp-block-group-is-layout-constrained\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--50);padding-right:var(--wp--preset--spacing--50);padding-bottom:var(--wp--preset--spacing--50);padding-left:var(--wp--preset--spacing--50)\">\n<div class=\"wp-block-group alignwide animated slideInUp has-background has-global-padding is-layout-constrained wp-container-core-group-is-layout-22 wp-block-group-is-layout-constrained\" style=\"border-radius:16px;background-color:#914e06;padding-top:var(--wp--preset--spacing--50);padding-right:var(--wp--preset--spacing--40);padding-bottom:var(--wp--preset--spacing--50);padding-left:var(--wp--preset--spacing--40)\">\n<div class=\"wp-block-group alignwide is-vertical is-content-justification-stretch is-layout-flex wp-container-core-group-is-layout-18 wp-block-group-is-layout-flex\">\n<h2 class=\"wp-block-heading has-text-align-center animated slideInUp has-body-font-family\"><strong>The Advanced Closed Loop System (ACLS)<\/strong>  <\/h2>\n\n\n\n<p class=\"has-text-align-center has-medium-font-size wp-block-paragraph\" style=\"margin-top:var(--wp--preset--spacing--10)\">The ACLS is an&nbsp;ESA&nbsp;rack that converts carbon dioxide and water into oxygen and methane. This is very different from the NASA oxygen-generating rack that is reliant on a steady supply of water from Earth in order to generate oxygen. This water-saving capability will reduce the need to launch an extra 400 liters of water in cargo resupply per year. 50% of the carbon dioxide that it processes can be converted to oxygen and by itself it can regenerate enough oxygen for 3 astronauts. The other 50% of carbon dioxide is jettisoned from the ISS along with the methane that is generated. ACLS has <strong>three subsystems<\/strong>&nbsp;:<\/p>\n<\/div>\n\n\n\n<div style=\"height:var(--wp--preset--spacing--30)\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-8 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"border-top-color:var(--wp--preset--color--contrast-3);border-top-width:1px;padding-top:var(--wp--preset--spacing--30);padding-right:var(--wp--preset--spacing--30);padding-bottom:var(--wp--preset--spacing--10);padding-left:var(--wp--preset--spacing--30)\">\n<h4 class=\"wp-block-heading has-text-align-center has-body-font-family has-large-font-size\" style=\"padding-top:1px;text-decoration:underline\"><strong>The Carbon dioxide Concentration Assembly (CCA) <\/strong><\/h4>\n\n\n\n<h5 class=\"wp-block-heading has-text-align-center has-body-font-family has-medium-font-size\">uses an amine reaction to absorb and concentrate carbon dioxide from cabin air to keep carbon dioxide within acceptable levels.<\/h5>\n\n\n\n<p class=\"has-text-align-center has-medium-font-size wp-block-paragraph\">The carbon dioxide is removed from the station air by an amine scrubber<\/p>\n\n\n\n<div class=\"wp-block-group is-vertical is-content-justification-stretch is-layout-flex wp-container-core-group-is-layout-19 wp-block-group-is-layout-flex\">\n<hr class=\"wp-block-separator has-text-color has-contrast-3-color has-alpha-channel-opacity has-contrast-3-background-color has-background is-style-wide\"\/>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"border-top-color:var(--wp--preset--color--contrast-3);border-top-width:1px;padding-top:var(--wp--preset--spacing--30);padding-right:var(--wp--preset--spacing--30);padding-bottom:var(--wp--preset--spacing--10);padding-left:var(--wp--preset--spacing--30)\">\n<h4 class=\"wp-block-heading has-text-align-center has-body-font-family has-large-font-size\" style=\"padding-top:1px;text-decoration:underline\"><strong>the Carbon dioxide Reprocessing Assembly (CRA)<\/strong><\/h4>\n\n\n\n<h5 class=\"wp-block-heading has-text-align-center has-body-font-family has-medium-font-size\">A \u2018Sabatier reactor\u2019 reacts CO<sub>2<\/sub>&nbsp;from CCA with hydrogen from the OGA to produce water and methane.<\/h5>\n\n\n\n<p class=\"has-text-align-center wp-block-paragraph\">the amine is removed from the scrubber by steam and converted to methane and water by a&nbsp;Sabatier reaction&nbsp;using hydrogen electrolyically produced from water.<\/p>\n\n\n\n<div class=\"wp-block-group is-vertical is-content-justification-stretch is-layout-flex wp-container-core-group-is-layout-20 wp-block-group-is-layout-flex\">\n<hr class=\"wp-block-separator has-text-color has-contrast-3-color has-alpha-channel-opacity has-contrast-3-background-color has-background is-style-wide\"\/>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"border-top-color:var(--wp--preset--color--contrast);border-top-width:2px;padding-top:var(--wp--preset--spacing--30);padding-right:var(--wp--preset--spacing--30);padding-bottom:var(--wp--preset--spacing--10);padding-left:var(--wp--preset--spacing--30)\">\n<h4 class=\"wp-block-heading has-text-align-center has-body-font-family\" style=\"text-decoration:underline\"><strong>The Oxygen Generation Assembly (OGA)<\/strong><\/h4>\n\n\n\n<h5 class=\"wp-block-heading has-text-align-center has-body-font-family has-medium-font-size\">an electrolyser that separates water into oxygen and hydrogen.<\/h5>\n\n\n\n<p class=\"has-text-align-center wp-block-paragraph\"> The methane is vented, the water is recycled by electrolysis producing hydrogen and oxygen making the cycle repeat <\/p>\n\n\n\n<div class=\"wp-block-group is-vertical is-content-justification-stretch is-layout-flex wp-container-core-group-is-layout-21 wp-block-group-is-layout-flex\">\n<hr class=\"wp-block-separator has-text-color has-contrast-3-color has-alpha-channel-opacity has-contrast-3-background-color has-background is-style-wide\"\/>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">The ACLS is a technology demonstrator (planned to operate from 1 to 2 years) but if it is successful it will be left on board the ISS permanently. It was delivered on the&nbsp;Kounotori 7&nbsp;launch in September 2018 and installed in the&nbsp;<em>Destiny<\/em>&nbsp;module. A year after delivery, most of it was working and new parts were expected to get all three subsystems fully functional in 2020.<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull has-background is-layout-flow wp-block-group-is-layout-flow\" style=\"background-color:#f5eac1;padding-top:6vw;padding-right:6vw;padding-bottom:6vw;padding-left:6vw\">\n<div class=\"wp-block-group is-vertical is-nowrap is-layout-flex wp-container-core-group-is-layout-24 wp-block-group-is-layout-flex\" style=\"padding-right:0;padding-left:0\">\n<p class=\"animated slideInLeft has-text-color wp-block-paragraph\" style=\"color:#000000;font-size:6vw;font-style:normal;font-weight:700;letter-spacing:0px;line-height:0.9;text-decoration:none;text-transform:none\">Power and thermal control.<\/p>\n\n\n\n<h2 class=\"wp-block-heading animated slideInLeft has-base-color has-text-color has-link-color has-body-font-family wp-elements-f5f0af5fa25514428804de3f0bdbb062\" style=\"text-decoration:underline\"><strong>Solar arrays<\/strong><\/h2>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignwide is-vertical is-nowrap is-layout-flex wp-container-core-group-is-layout-25 wp-block-group-is-layout-flex\" style=\"padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-9 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column animated slideInLeft is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33.38%\">\n<p class=\"animated slideInLeft has-base-color has-text-color has-link-color wp-elements-5281c09f4cb0e31fc3f79c8962ebb640 wp-block-paragraph\">Double-sided&nbsp;solar arrays&nbsp;provide&nbsp;electrical power&nbsp;to the ISS. These bifacial cells collect direct sunlight on one side and light&nbsp;reflected off&nbsp;from the Earth on the other, and are more efficient and operate at a lower temperature than single-sided cells commonly used on Earth. Each ISS solar array wing (often abbreviated &#8220;SAW&#8221;) consists of two retractable &#8220;blankets&#8221; of solar cells with a mast between them. Each wing is the largest ever deployed in space, weighing over 2,400 pounds and using nearly 33,000 solar arrays, each measuring 8-cm square with 4,100 diodes. When fully extended, each is 35 metres (115&nbsp;ft) in length and 12 metres (39&nbsp;ft) wide. Each SAW is capable of generating nearly 31 Kilowatts (kW) of direct current power. When retracted, each wing folds into a solar array blanket box just 51 centimetres (20&nbsp;in) high and 4.57 metres (15.0&nbsp;ft) in length.<\/p>\n\n\n\n<p class=\"animated slideInLeft has-base-color has-text-color has-link-color wp-elements-586276acaf534e9ae5ef438b97795252 wp-block-paragraph\">The Russian segment of the station, like most spacecraft, uses 28&nbsp;V&nbsp;low voltage&nbsp;DC&nbsp;from two rotating solar arrays mounted on&nbsp;<em>Zvezda<\/em>. The USOS uses 130\u2013180&nbsp;V&nbsp;DC from the USOS&nbsp;PV array, power is stabilised and distributed at 160&nbsp;V&nbsp;DC and converted to the user-required 124&nbsp;V&nbsp;DC. The&nbsp;higher distribution voltage&nbsp;allows smaller, lighter conductors, at the expense of crew safety. The two station segments share power with converters. The USOS solar arrays are arranged as four wing pairs, for a total production of 75 to 90 kilowatts.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33%\">\n<div style=\"height:2vw\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<figure class=\"wp-block-image size-large animated slideInRight\"><img loading=\"lazy\" decoding=\"async\" width=\"675\" height=\"1024\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/P4_deployed-675x1024.jpg\" alt=\"\" class=\"wp-image-895\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/P4_deployed-675x1024.jpg 675w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/P4_deployed-198x300.jpg 198w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/P4_deployed-768x1165.jpg 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/P4_deployed-rotated.jpg 844w\" sizes=\"auto, (max-width: 675px) 100vw, 675px\" \/><figcaption class=\"wp-element-caption\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-base-color\">One of the eight truss mounted pairs of USOS solar arrays<\/mark><\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33.62%\">\n<figure class=\"wp-block-image size-full animated slideInRight\"><img loading=\"lazy\" decoding=\"async\" width=\"598\" height=\"900\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss-solar-arrays-nasa-2-rotated.jpg\" alt=\"\" class=\"wp-image-905\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss-solar-arrays-nasa-2-rotated.jpg 598w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/iss-solar-arrays-nasa-2-199x300.jpg 199w\" sizes=\"auto, (max-width: 598px) 100vw, 598px\" \/><\/figure>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-10 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:69%\">\n<figure class=\"wp-block-image size-full animated slideInLeft\"><img loading=\"lazy\" decoding=\"async\" width=\"786\" height=\"493\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/EATCS-1.png\" alt=\"\" class=\"wp-image-901\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/EATCS-1.png 786w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/EATCS-1-300x188.png 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/EATCS-1-768x482.png 768w\" sizes=\"auto, (max-width: 786px) 100vw, 786px\" \/><figcaption class=\"wp-element-caption\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-base-color\">ISS External Active Thermal Control System (EATCS) diagram<\/mark><\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33%\">\n<p class=\"animated slideInRight has-base-color has-text-color has-link-color wp-elements-ccdaa46a50d02573603cbc1a3c4460d1 wp-block-paragraph\">These arrays normally track the Sun to maximise power generation. In the complete configuration, the solar arrays track the Sun by rotating the&nbsp;<em>alpha&nbsp;gimbal<\/em>&nbsp;once per orbit; the&nbsp;<em>beta gimbal<\/em>&nbsp;follows slower changes in the angle of the Sun to the orbital plane. The&nbsp;Night Glider mode&nbsp;aligns the solar arrays parallel to the ground at night to reduce the significant aerodynamic drag at the station&#8217;s relatively low orbital altitude. Several different tracking modes are used in operations, ranging from full Sun-tracking, to the drag-reduction mode (<em>night glider<\/em>&nbsp;and&nbsp;<em>Sun slicer<\/em>&nbsp;modes), to a drag-maximization mode used to lower the altitude.<\/p>\n\n\n\n<p class=\"animated slideInRight has-base-color has-text-color has-link-color wp-elements-5dc2afed3fab1c06e6cf74e912d877fc wp-block-paragraph\">Altogether, the eight solar array wings can generate about 240 kilowatts in direct sunlight, or about 84 to 120 kilowatts average power (cycling between sunlight and shade).<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading animated slideInUp has-base-color has-text-color has-link-color has-body-font-family wp-elements-078cef9f53f7c023127d7d04c5e34730\" style=\"text-decoration:underline\"><strong>Batteries<\/strong><\/h2>\n\n\n\n<p class=\"animated slideInUp has-base-color has-text-color has-link-color wp-elements-424195f53481706f42805059599770e3 wp-block-paragraph\">The station originally used rechargeable&nbsp;nickel\u2013hydrogen batteries&nbsp;(NiH<sub>2<\/sub>) for continuous power during the 45 minutes of every 90-minute orbit that it is eclipsed by the Earth. The batteries are recharged on the day side of the orbit. They had a 6.5-year lifetime (over 37,000 charge\/discharge cycles) and were regularly replaced over the anticipated 20-year life of the station. Starting in 2016, the nickel\u2013hydrogen batteries were replaced by&nbsp;lithium-ion batteries, which are expected to last until the end of the ISS program.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull has-global-padding is-layout-constrained wp-container-core-group-is-layout-29 wp-block-group-is-layout-constrained\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--50);padding-right:var(--wp--preset--spacing--50);padding-bottom:var(--wp--preset--spacing--50);padding-left:var(--wp--preset--spacing--50)\">\n<div class=\"wp-block-group alignwide has-global-padding is-layout-constrained wp-container-core-group-is-layout-28 wp-block-group-is-layout-constrained\">\n<h2 class=\"wp-block-heading has-text-align-center is-style-default animated slideInUp has-body-font-family\" style=\"text-decoration:underline\"><strong>Thermal control<\/strong><\/h2>\n\n\n\n<div class=\"wp-block-group is-vertical is-content-justification-center is-layout-flex wp-container-core-group-is-layout-27 wp-block-group-is-layout-flex\">\n<p class=\"has-text-align-center animated slideInUp has-body-font-family wp-block-paragraph\">The station&#8217;s systems and experiments consume a large amount of electrical power, almost all of which is converted to heat. To keep the internal temperature within workable limits, a passive thermal control system (PTCS) is made of external surface materials, insulation such as MLI, and heat pipes. If the PTCS cannot keep up with the heat load, an External Active Thermal Control System (EATCS) maintains the temperature. <\/p>\n<\/div>\n\n\n\n<div style=\"height:var(--wp--preset--spacing--40)\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-11 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:40%\">\n<p class=\"animated slideInLeft wp-block-paragraph\">The EATCS consists of an internal, non-toxic, water coolant loop used to cool and dehumidify the atmosphere, which transfers collected heat into an external liquid&nbsp;ammonia&nbsp;loop. From the heat exchangers, ammonia is pumped into external radiators that emit heat as infrared radiation, then back to the station.&nbsp;The EATCS provides cooling for all the US pressurised modules, including&nbsp;<em>Kib\u014d<\/em>&nbsp;and&nbsp;<em>Columbus<\/em>, as well as the main power distribution electronics of the S0, S1 and P1 trusses. It can reject up to 70&nbsp;kW. This is much more than the 14&nbsp;kW of the Early External Active Thermal Control System (EEATCS) via the Early Ammonia Servicer (EAS), which was launched on&nbsp;STS-105&nbsp;and installed onto the P6 Truss.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<figure class=\"wp-block-image size-large is-style-rounded animated slideInUp is-style-rounded--8a80700a688e426802aa16ae4c80a719\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"669\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/EATCS_Overview-1024x669.png\" alt=\"\" class=\"wp-image-962\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/EATCS_Overview-1024x669.png 1024w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/EATCS_Overview-300x196.png 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/EATCS_Overview-768x502.png 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/EATCS_Overview.png 1280w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">EATCS schematic overview<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<div style=\"height:var(--wp--preset--spacing--40)\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-12 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<figure class=\"wp-block-image size-full is-style-rounded animated slideInUp is-style-rounded--ce2bc1d114232a41a3f4ee09c8827261\"><img loading=\"lazy\" decoding=\"async\" width=\"553\" height=\"466\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/DDCU_cold_plate_design.png\" alt=\"\" class=\"wp-image-966\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/DDCU_cold_plate_design.png 553w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/DDCU_cold_plate_design-300x253.png 300w\" sizes=\"auto, (max-width: 553px) 100vw, 553px\" \/><figcaption class=\"wp-element-caption\">DDCU cold plate design<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large animated slideInUp\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"372\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Early_Ammonia_Servicer-1024x372.png\" alt=\"\" class=\"wp-image-967\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Early_Ammonia_Servicer-1024x372.png 1024w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Early_Ammonia_Servicer-300x109.png 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Early_Ammonia_Servicer-768x279.png 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Early_Ammonia_Servicer-1536x558.png 1536w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Early_Ammonia_Servicer.png 1920w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Early Ammonia Servicer<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:40%\">\n<p class=\"animated slideInRight wp-block-paragraph\">There are two independent Loops (Loop A &amp; Loop B) that combined make up the EATCS. The EATCS Loops perform three primary functions:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li class=\"animated slideInRight\">Heat Collection &#8211; Each Loop draws heat from five Heat Exchangers (HXs) mounted on the&nbsp;Destiny Laboratory,&nbsp;Node-2&nbsp;&amp;&nbsp;Node-3&nbsp;as well as cold plates under three DC-to-DC Conversion Units (DDCUs)<\/li>\n\n\n\n<li class=\"animated slideInRight\">Heat Transportation &#8211; The Pump Module (PM) provides flow and accumulator functions and maintains proper temperature control at the pump outlet for each Loop. <\/li>\n\n\n\n<li class=\"animated slideInRight\">Heat Rejection &#8211; Ammonia passes from the ATA through a two way path of the Flex Hose Rotary Coupler (FHRC) where heat captured while passing through the Heat Exchangers is directed to be expelled through the Heat Rejection System Radiators (HRSRs).<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<div class=\"wp-block-group alignfull has-background is-layout-flow wp-block-group-is-layout-flow\" style=\"background-color:#f2f0e9\">\n<div style=\"height:70px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-columns alignwide are-vertically-aligned-center is-layout-flex wp-container-core-columns-is-layout-13 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<h2 class=\"wp-block-heading animated slideInLeft has-base-color has-text-color has-link-color has-body-font-family wp-elements-ae98e394368ae093ea38ed09dde3eab6\" style=\"text-decoration:underline\"><strong>Electrical system of the International Space Station<\/strong><\/h2>\n\n\n\n<p class=\"has-text-color wp-block-paragraph\" style=\"color:#000000;font-size:clamp(18.959px, 1.185rem + ((1vw - 3.2px) * 1), 30px);line-height:1.1\"><\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<hr class=\"wp-block-separator has-text-color has-css-opacity has-background is-style-wide\" style=\"background-color:#000000;color:#000000\"\/>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-14 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full animated slideInUp\"><img loading=\"lazy\" decoding=\"async\" width=\"918\" height=\"560\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Electrical_Power_Distribution.png\" alt=\"\" class=\"wp-image-958\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Electrical_Power_Distribution.png 918w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Electrical_Power_Distribution-300x183.png 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Electrical_Power_Distribution-768x468.png 768w\" sizes=\"auto, (max-width: 918px) 100vw, 918px\" \/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"animated slideInRight has-base-color has-text-color has-link-color wp-elements-11be9352706dede7c2b27b41a7de267b wp-block-paragraph\">The&nbsp;<strong>electrical system of the International Space Station<\/strong>&nbsp;is a critical resource for the&nbsp;International Space Station&nbsp;(ISS) because it allows the crew to live comfortably, to safely operate the station, and to perform scientific experiments. The ISS electrical system uses&nbsp;solar cells&nbsp;to directly convert sunlight to&nbsp;electricity. Large numbers of cells are assembled in arrays to produce high power levels. This method of harnessing&nbsp;solar power&nbsp;is called&nbsp;photovoltaics.<\/p>\n\n\n\n<p class=\"animated slideInRight has-base-color has-text-color has-link-color wp-elements-63773b644e329487412a8b0ee79db63e wp-block-paragraph\">The process of collecting sunlight, converting it to electricity, and managing and distributing this electricity builds up excess heat that can damage spacecraft equipment. This heat must be eliminated for reliable operation of the&nbsp;space station&nbsp;in orbit. The ISS power system uses&nbsp;radiators&nbsp;to dissipate the heat away from the spacecraft. The radiators are shaded from sunlight and aligned toward the cold void of deep space.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"animated slideInRight has-text-color has-extra-small-font-size wp-block-paragraph\" style=\"color:#000000\">No darkness would ever settle upon those lamps, as no darkness had settled upon them for hundreds of years. It seemed dreadful that the town should blaze for ever in the same spot; dreadful at least to people going away to adventure upon the sea, and beholding it as a circumscribed mound, eternally burnt, eternally scarred. From the deck of the ship the great city appeared a crouched and cowardly figure, a sedentary miser.<\/p>\n<\/div>\n<\/div>\n\n\n\n<div style=\"height:40px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\">\n<div class=\"wp-block-columns alignfull is-layout-flex wp-container-core-columns-is-layout-16 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<div class=\"wp-block-cover is-light animated slideInLeft\" style=\"min-height:600px;aspect-ratio:unset;aspect-ratio:unset;\"><span aria-hidden=\"true\" class=\"wp-block-cover__background has-background-dim-100 has-background-dim\" style=\"background-color:#f6f6f6\"><\/span><div class=\"wp-block-cover__inner-container is-layout-flow wp-block-cover-is-layout-flow\">\n<figure class=\"wp-block-image aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1280\" height=\"853\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ECLSS_at_the_ECLSS_Test_Facility.jpg\" alt=\"\" class=\"wp-image-969\" style=\"width:453px;height:auto\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ECLSS_at_the_ECLSS_Test_Facility.jpg 1280w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ECLSS_at_the_ECLSS_Test_Facility-300x200.jpg 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ECLSS_at_the_ECLSS_Test_Facility-1024x682.jpg 1024w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ECLSS_at_the_ECLSS_Test_Facility-768x512.jpg 768w\" sizes=\"auto, (max-width: 1280px) 100vw, 1280px\" \/><figcaption class=\"wp-element-caption\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-base-color\">The three ECLSS racks on display at the Marshall Space Flight Center ECLSS Test Facility in 2012. From left to right, the Water Recovery System (Rack 1), WRS (Rack 2) and Oxygen Generating System.<\/mark><\/figcaption><\/figure>\n<\/div><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">The Water Recovery System consists of a Urine Processor Assembly and a Water Processor Assembly, housed in two of the three ECLSS racks.<\/p>\n\n\n\n<p class=\"animated slideInUp wp-block-paragraph\">The Urine Processor Assembly uses a low pressure vacuum distillation process that uses a centrifuge to compensate for the lack of gravity and thus aid in separating liquids and gasses.&nbsp;The Urine Processor Assembly is designed to handle a load of 9&nbsp;kg\/day, corresponding to the needs of a 6-person crew.&nbsp;Although the design called for recovery of 85% of the water content, subsequent experience with calcium sulfate precipitation&nbsp;(in the free-fall conditions present on the ISS, calcium levels in urine are elevated due to bone density loss) has led to a revised operational level of recovering 70% of the water content.<\/p>\n\n\n\n<p class=\"animated slideInUp wp-block-paragraph\">Water from the Urine Processor Assembly and from waste water sources are combined to feed the Water Processor Assembly that filters out gasses and solid materials before passing through filter beds and then a high-temperature catalytic reactor assembly. The water is then tested by onboard sensors and unacceptable water is cycled back through the water processor assembly.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\" style=\"padding-top:1em;padding-right:1em;padding-bottom:1em;padding-left:1em\">\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\">\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-15 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:320px\">\n<p class=\"animated slideInLeft has-x-large-font-size wp-block-paragraph\" style=\"line-height:1.6;text-decoration:underline\"><strong>Water recovery system<\/strong><\/p>\n\n\n\n<p class=\"animated slideInUp wp-block-paragraph\">The ISS has two water recovery systems.\u00a0<em>Zvezda<\/em>\u00a0contains a\u00a0water\u00a0recovery system that processes water vapor from the atmosphere that could be used for drinking in an emergency but is normally fed to the\u00a0Elektron\u00a0system to produce\u00a0oxygen. The American segment has a Water Recovery System installed during\u00a0STS-126 that can process water vapour collected from the atmosphere and\u00a0urine\u00a0into water that is intended for drinking. The Water Recovery System was installed initially in\u00a0<em>Destiny<\/em>\u00a0on a temporary basis in November 2008 and moved into\u00a0<em>Tranquility<\/em>\u00a0(Node 3) in February 2010.<\/p>\n<\/div>\n<\/div>\n\n\n\n<figure class=\"wp-block-image size-large animated slideInRight\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1024\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Recycling_water_on_the_ISS_How_it_works_pt._2_pillars-1024x1024.png\" alt=\"\" class=\"wp-image-1032\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Recycling_water_on_the_ISS_How_it_works_pt._2_pillars-1024x1024.png 1024w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Recycling_water_on_the_ISS_How_it_works_pt._2_pillars-300x300.png 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Recycling_water_on_the_ISS_How_it_works_pt._2_pillars-150x150.png 150w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Recycling_water_on_the_ISS_How_it_works_pt._2_pillars-768x768.png 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Recycling_water_on_the_ISS_How_it_works_pt._2_pillars-1536x1536.png 1536w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/Recycling_water_on_the_ISS_How_it_works_pt._2_pillars.png 1920w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-media-text alignwide has-media-on-the-right is-stacked-on-mobile is-vertically-aligned-center animated slideInUp has-background\" style=\"background-color:#f1f5c7;grid-template-columns:auto 39%\"><div class=\"wp-block-media-text__content\">\n<div class=\"wp-block-group is-layout-flow wp-block-group-is-layout-flow\" style=\"padding-top:2em;padding-right:2em;padding-bottom:2em;padding-left:2em\">\n<h2 class=\"wp-block-heading animated slideInLeft has-base-color has-text-color has-link-color wp-elements-7bb3708d875412971d2b6f2ff4c539f3\" style=\"text-decoration:underline\"><strong>Communication systems<\/strong><\/h2>\n\n\n\n<p class=\"animated slideInLeft has-base-color has-text-color has-link-color wp-elements-516251f23e7f6041799ecc1d68967913 wp-block-paragraph\">Radio communications provide&nbsp;telemetry&nbsp;and scientific data links between the station and&nbsp;mission control centres. Radio links are also used during&nbsp;rendezvous and docking procedures&nbsp;and for audio and video communication between crew members, flight controllers and family members. As a result, the ISS is equipped with internal and external communication systems used for different purposes.<\/p>\n\n\n\n<p class=\"animated slideInLeft has-base-color has-text-color has-link-color wp-elements-16848111cd5d5131892d9436dbb29c0b wp-block-paragraph\">The Russian Orbital Segment communicates directly with the ground via the&nbsp;<em>Lira<\/em>&nbsp;antenna&nbsp;mounted to&nbsp;<em>Zvezda<\/em>.&nbsp;The&nbsp;<em>Lira<\/em>&nbsp;antenna also has the capability to use the&nbsp;<em>Luch<\/em>&nbsp;data relay satellite system. Another Russian communications system is the&nbsp;Voskhod-M, which enables internal telephone communications between&nbsp;<em>Zvezda<\/em>,&nbsp;<em>Zarya<\/em>,&nbsp;<em>Pirs<\/em>,&nbsp;<em>Poisk<\/em>, and the USOS and provides a VHF radio link to ground control centres via antennas on&nbsp;<em>Zvezda<\/em>&#8216;s&nbsp;exterior. The&nbsp;US Orbital Segment&nbsp;(USOS) makes use of two separate radio links:&nbsp;S band&nbsp;(audio, telemetry, commanding \u2013 located on the P1\/S1 truss) and&nbsp;K<sub>u<\/sub>&nbsp;band&nbsp;(audio, video and data \u2013 located on the&nbsp;Z1 truss) systems. These transmissions are routed via the United States&nbsp;Tracking and Data Relay Satellite&nbsp;System (TDRSS) in&nbsp;geostationary orbit, allowing for almost continuous real-time communications with&nbsp;Christopher C. Kraft Jr. Mission Control Center&nbsp;(MCC-H) in&nbsp;Houston.&nbsp;Data channels for the Canadarm2, European&nbsp;<em>Columbus<\/em>&nbsp;laboratory and Japanese&nbsp;<em>Kib\u014d<\/em>&nbsp;modules were originally also routed via the S band and K<sub>u<\/sub>&nbsp;band systems, with the&nbsp;European Data Relay System&nbsp;and a similar Japanese system intended to eventually complement the TDRSS in this role.&nbsp;Communications between modules are carried on an internal&nbsp;wireless network.<\/p>\n<\/div>\n<\/div><figure class=\"wp-block-media-text__media\"><img loading=\"lazy\" decoding=\"async\" width=\"866\" height=\"1024\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS_Communication_Systems-866x1024.png\" alt=\"\" class=\"wp-image-1182 size-full\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS_Communication_Systems-866x1024.png 866w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS_Communication_Systems-254x300.png 254w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS_Communication_Systems-768x908.png 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS_Communication_Systems-1299x1536.png 1299w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/ISS_Communication_Systems.png 1402w\" sizes=\"auto, (max-width: 866px) 100vw, 866px\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<div class=\"wp-block-media-text alignwide is-stacked-on-mobile is-vertically-aligned-center animated slideInUp has-background\" style=\"background-color:#fffdea\"><figure class=\"wp-block-media-text__media\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"680\" src=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/main-qimg-94795b84df5bf458b8601e8fae21e20c-c-1024x680.jpg\" alt=\"\" class=\"wp-image-1185 size-full\" srcset=\"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/main-qimg-94795b84df5bf458b8601e8fae21e20c-c-1024x680.jpg 1024w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/main-qimg-94795b84df5bf458b8601e8fae21e20c-c-300x199.jpg 300w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/main-qimg-94795b84df5bf458b8601e8fae21e20c-c-768x510.jpg 768w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/main-qimg-94795b84df5bf458b8601e8fae21e20c-c-1536x1020.jpg 1536w, http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-content\/uploads\/2024\/06\/main-qimg-94795b84df5bf458b8601e8fae21e20c-c-2048x1360.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure><div class=\"wp-block-media-text__content\">\n<p class=\"animated slideInRight has-base-color has-text-color has-link-color wp-elements-ea0061814cd8ed7d7eae188881143a82 wp-block-paragraph\">UHF radio&nbsp;is used by astronauts and cosmonauts conducting EVAs and other spacecraft that dock to or undock from the station.&nbsp;Automated spacecraft are fitted with their own communications equipment; the ATV used a&nbsp;laser&nbsp;attached to the spacecraft and the Proximity Communications Equipment attached to&nbsp;<em>Zvezda<\/em>&nbsp;to accurately dock with the station.<\/p>\n\n\n\n<p class=\"animated slideInRight has-base-color has-text-color has-link-color wp-elements-2bdaaac57a2fed4cf17ff70c00969a47 wp-block-paragraph\">The ISS is equipped with about 100&nbsp;IBM\/Lenovo ThinkPad&nbsp;and&nbsp;HP ZBook 15&nbsp;laptop computers. The laptops have run&nbsp;Windows 95,&nbsp;Windows 2000,&nbsp;Windows XP,&nbsp;Windows 7,&nbsp;Windows 10&nbsp;and&nbsp;Linux&nbsp;operating systems.&nbsp;Each computer is a&nbsp;commercial off-the-shelf&nbsp;purchase which is then modified for safety and operation including updates to connectors, cooling and power to accommodate the station&#8217;s 28V DC power system and weightless environment. Heat generated by the laptops does not rise but stagnates around the laptop, so additional forced ventilation is required. Portable Computer System (PCS) laptops connect to the Primary Command &amp; Control computer (C&amp;C MDM) as remote terminals via a USB to&nbsp;1553&nbsp;adapter.&nbsp;Station Support Computer (SSC) laptops aboard the ISS are connected to the station&#8217;s&nbsp;wireless LAN&nbsp;via&nbsp;Wi-Fi&nbsp;and ethernet, which connects to the ground via K<sub>u<\/sub>&nbsp;band. While originally this provided speeds of 10&nbsp;Mbit\/s&nbsp;download and 3&nbsp;Mbit\/s upload from the station,&nbsp;NASA upgraded the system in late August 2019 and increased the speeds to 600&nbsp;Mbit\/s.&nbsp;Laptop hard drives occasionally fail and must be replaced.&nbsp;Other computer hardware failures include instances in 2001, 2007 and 2017; some of these failures have required EVAs to replace computer modules in externally mounted devices.<\/p>\n\n\n\n<p class=\"animated slideInRight has-base-color has-text-color has-link-color wp-elements-213eaadd32daa487fdcd0a9b52ba2903 wp-block-paragraph\">The operating system used for key station functions is the&nbsp;Debian&nbsp;Linux distribution.&nbsp;The migration from&nbsp;Microsoft Windows&nbsp;to Linux was made in May 2013 for reasons of reliability, stability and flexibility.<\/p>\n\n\n\n<p class=\"animated slideInRight has-base-color has-text-color has-link-color wp-elements-3e007cae91262a748acac11a6cb64921 wp-block-paragraph\">In 2017, an SG100 Cloud Computer was launched to the ISS as part of OA-7 mission.&nbsp;It was manufactured by&nbsp;NCSIST&nbsp;of&nbsp;Taiwan&nbsp;and designed in collaboration with&nbsp;Academia Sinica, and&nbsp;National Central University&nbsp;under contract for NASA.<\/p>\n\n\n\n<p class=\"animated slideInRight has-base-color has-text-color has-link-color wp-elements-3e287579590a2d222aa0ca9a169f07fe wp-block-paragraph\">ISS crew members have access to the&nbsp;Internet, and thus&nbsp;the web.&nbsp;This was first enabled in 2010, allowing NASA astronaut&nbsp;T.J. Creamer&nbsp;to make the first&nbsp;tweet&nbsp;from space.&nbsp;Access is achieved via an Internet-enabled computer in Houston, using&nbsp;remote desktop mode, thereby protecting the ISS from virus infection and hacking attempts.<\/p>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>On Board systems of the ISS the systems that act as the stations life support The critical systems that are the sole reason as to why life is even allowed to exist in the ISS make up the Environmental Control and Life Support System&nbsp;(ECLSS) and include the atmosphere control system that provides or controls&nbsp;atmospheric pressure [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-130","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-json\/wp\/v2\/pages\/130","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-json\/wp\/v2\/comments?post=130"}],"version-history":[{"count":290,"href":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-json\/wp\/v2\/pages\/130\/revisions"}],"predecessor-version":[{"id":1504,"href":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-json\/wp\/v2\/pages\/130\/revisions\/1504"}],"wp:attachment":[{"href":"http:\/\/itnas.civil.duth.gr\/cmss\/2024a\/wp-json\/wp\/v2\/media?parent=130"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}