This is known as gravitational theory, the extrapolation of an idea originally conceived by Isaac Newton in the 17th century, and today increasingly dismissed by most clear-thinking people who have their feet firmly on the ground. WHY DO THINGS FLOAT in space when they’re beyond 100km from the Earth? Does gravity magically stop affecting objects at this distance? The official answer is that above 100km objects are essentially free-falling, but if something is traveling fast enough laterally, like the space shuttle at 28,000 km/h, then this speed will cause the object to perpetually fall along the convex curve of the Earth, thereby never actually reaching the ground-hence maintaining itself “in orbit.” While graphite has a high melting point (5500☌), it is also an excellent conductor of heat-although their spacecraft would most likely fall apart long before it cooked the astronauts to a crisp! Humans cannot survive exposures above 70☌. NASA uses aluminum, magnesium, titanium, and epoxy-graphite composites to build its spacecraft-all of which would melt in these high temperatures of the thermosphere.Īluminum and magnesium both melt at 660☌, titanium at 1668☌. A crematorium reaches 1000☌, and a blast furnace for melting iron can go as high as 2300☌. Beyond this point, the heat increases dramatically, rising rapidly up to 125 miles, where temperatures can reach 2500☌!įOR REFERENCE: the oven in your kitchen can hit 240☌ max. This atmospheric layer starts at about 50 miles high, where temperatures start to rise until the Kármán line is reached at 62 miles. FORGET about the lethal Van Allen radiation belts, that stretch for thousands of miles around the Earth, the number one reason why nothing has ever gone into space is THE THERMOSPHERE: