Thursday 10 March 2016

167) “Satellites are allegedly floating around in the thermosphere where temperatures are claimed to be upwards of 4,530 degrees Fahrenheit. The metals used in satellites, however, such as aluminum, gold and titanium have melting points of 1,221, 1,948, and 3,034 degrees respectively, all far lower than they could possibly handle.

A slightly more technical claim, but still an ignorant one. What is temperature? It’s the amount of energy bound up in the agitated motion of atoms. And it’s true that there are highly agitated atoms in the orbital altitude of many satellites. It’s called the thermosphere and it’s well known to science.

Why is Dubay wrong then?

Because those atoms are spread incredibly thin! 

They are right up in the region between the upper atmosphere and the vacuum of space. If they were as closely packed as the atoms in the lower atmosphere, it would indeed be too hot, in the normal everyday sense. 

But as there are only a few of these “hot” atoms in every cubic metre of space around the satellites, they have no effect. 

The highly diluted gas in this layer can reach 2,500 °C (4,530 °F) during the day. Even though the temperature is so high, one would not feel warm in the thermosphere, because it is so near vacuum that there is not enough contact with the few atoms of gas to transfer much heat. A normal thermometer would be significantly below 0 °C (32 °F), because the energy lost by thermal radiation would exceed the energy acquired from the atmospheric gas by direct contact. In the anacoustic zone above 160 kilometres (99 mi), the density is so low that molecular interactions are too infrequent to permit the transmission of sound. [Wikipedia].

For a more technical explanation start here:

But as always with Wikipedia, just use it as a starting point – check the references for yourself. if you want more detailed and precise descriptions of issues about heat and spacecraft, try these: 

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