What makes space so cold?
Answers
Answer:
The reason outer space is so cold is because cold is what you get when there is no source of heat nearby.
At our distance from the sun, if you put, say, a Mac Truck in space, the side facing the sun will quickly get hot enough to burn you. The reason is obvious: sunlight contains energy, and in near-Earth space, there is no atmosphere to filter that energy, so it’s even more intense than it is down here. Now, on Earth, if you put something out in the sun, it warms up. The air picks up some of that warmth and rises, and the resulting current wicks heat away. In space, none of that can happen. Space is like a giant thermos, a perfect insulator, so our hypothetical truck won’t just heat up to 140 degrees like a strip of asphalt on Earth—it’ll heat up to more like two hundred and fifty degrees.
Answer:
The reason outer space is so cold is because cold is what you get when there is no source of heat nearby. ... Objects in space cannot cool off by thermal conduction or convection, but they can cool off by radiating infrared light. All objects do this, and they radiate more the hotter they get.