level conditions. The atmosphere consists of 7936 nitrogen and 21jt oxygen, again very close to what the astronauts left on •arth. In an emergency ( asapBa }, cabin pressure is reduced. Carbon dioxide ia a waste product and must not be allowed to build up la the cabin. Therefore, canisters filled with lithi-UB hydroxide and activated charcoal remove carbon dioxide and odors ( aanaa ) fron the cabin's air. ?ans circulate the air around the cabin and through the canisters. Carbon dioxide reacts with lithium hydroxide to produce lithium carbonate and water vapor.
Two canisters are used at a time. With. four people abroad, an individual canister lasts 24 hours. They are changed alternately, that ifl one ia changed every 12,hours. As with other chores ( otfnaaHBoCTB ), responsibility for changing the carbon dioxide
absorbers is assigned to a different member of the crew each day.
The cabin's atmosphere Is controlled from panels. There are switches to select which source of oxygen you want to use. The oxygen supply ia carried,In the fora of a super-cold (cryogenic) liquid. Each. liquid-oxygen tank has beaters which vaporize some of the super-cold liquid.
If it gets too warm or too cold, one can adjust ( peryJiBRO-BSTI, ) the cabin temperature using the CABUf TEMP SWITCH. Below
this switch are controls tor the fans that circulate air through. lithium hydroxide canisters.
Electrical power tor the Orbiter ia generated by FUEL CEUiS. Oxygen and hydrogen are chemically combined In the celle to produce electricity. There is an important by-product ( noOoiHHfl
npOflyiT ) fron this reaction-water. About 3 kilograms of water is created every hour.
OrneTOTe Ha fi"np"ou:
1. Ms sero COCTOBT cacTetia^patfoTaomaa Ha aaoTBOM TOOJISW?
2. KaKRM otfpaaoM ywmcvca OKcaa yr.iiepo.na B Apyrae sanaxa H3 KopadJia?
3. KaK KOHTponnpyeTca cocToaHae aTuoci^epu B KopatfJie?
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RnoK yffl
TepOHH K TOKCTy TT

spaoeflight-KOOMiiiecKBfl nosaV mainly - Tsassw oopaaOM booster- ycKOpBTeJit descend- cnycKflTfcCH


fix - yRpenzJiTi> recover - npKBOAiTfc K noB-
TOpBOUy BOnOBbSlBBaBBB
payload- noJiesHaa aarpyaBa carry out " SUZOSBSi'tb

THS SPACE SHUTTLE
Until recently, every manned spacaflight was aa expensive mission. This was mainly because a new spacecraft had to be built for every flight and a new rocket to launch it.
However, the US now has a new kind of spacecraft - the space shuttle - that can be used again and again. It first went into orbit in 1981. Spaceflight will become much cheaper and there could be a manned mission every week.
The apace shuttle has wings and looks more like an aircraft then a spacecraft. It is launched into space by booster rockets.
On the way up to orbit, these fall away from the shuttle and descend into the sea by parachute so that they can be used. again. The shuttle goes on into orbit using fuel from a large tank fixed beneath it. This too drops away when the fuel is used,
and is not recovered.
/ Once in orbit, the shuttle carries out its mission. This
could be to place a satellite in orbit, or a special space laboratory.
THE RE-USABLE SPACECRAFT. Onoe its mission is over, the shu'-ttle returns to earth, earring any cargo back from space if necessary. It fires its engines to slow its motion and falls back to Earth, landing on a runway like an aircraft. Each shuttle should be able to make about 100 flights.
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