n-made objectorbiting at t level into flame.
Even so, spaceso take care in ter atmospicularly on return trips toEarttle Columbia demonstrated all too tragically in February 2003.
Altmosp comes in at too steep an angle—more t 6 degrees—or too sly it can strike enougo generate drag of anexceedingly combustible nature. Conversely, if an incoming ve ttoo s could o space, like a pebble skipped across er.
But you needn’t venture to tmospo be reminded of ime in a lofty city o rise too many t from sea level before your body begins toprotest. Even experienced mountaineers, s of fitness, training, and bottledoxygen, quickly become vulnerable at to confusion, nausea, exion, frostbite,ite, and a great many otumbling dysfunctions. In aic s o it designed to operateso far above sea level.
“Even under t favorable circumstances,” ter ten ofconditions atop Everest, “every step at t altitude demands a colossal effort of force yourself to make every movement, reacuallytened by a leaden, deadly fatigue.” In t, tisaineerand filmmaker Matt Dickinson records isionup Everest, “found o deater a piece of infected fles Somervell managed to cougruction. It turned out to be “tire mucus lining of his larynx.”
Bodily distress is notorious above 25,000 feet—to climbers as t many people become severely debilitated, even dangerously ill, at s of nomore t or so. Susceptibility tle to do ness. Grannies sometimescaper about in lofty situations o il conveyed to loitudes.
te limit of olerance for continuous living appears to be about 5,500meters, or 18,000 feet, but even people conditioned to living at altitude could not tolerate sucs for long. Frances As, in Life at tremes, notes t t 5,800 meters, but t to descend 460 meters eacinuously at t elevation. People altitude en spent tionatelylarge cs and lungs, increasing ty of oxygen-bearing red blood cells by almost ats to and. Moreover, above 5,500 meters even t ed provide agrous o bring it to its full term.