Final answer:
It would feel cold in the upper thermosphere despite the high temperatures due to the low density of air molecules, which results in minimal heat transfer to objects or human skin.
Step-by-step explanation:
Despite the high temperatures in the upper thermosphere, it would feel cold due to the thin density of air molecules. The concept of temperature in a physical sense is a measure of the average kinetic energy of the molecules in a substance. In the thermosphere, there are so few air molecules that even though they move at high speeds (thus giving rise to a high-temperature reading), they seldom collide with an object, such as a satellite or a human body, if one were present.
This rarity of collisions means that there is minimal transfer of heat to an object. In environments we typically experience, there are enough air molecules that when they collide with our skin, they impart kinetic energy that we perceive as heat. Since there are not enough molecules at the altitude of the thermosphere to effectively transfer heat, the high kinetic energy of individual molecules does not translate to a sensation of warmth on the skin. Thus, the ambient environment of the thermosphere would feel extremely cold to human skin.