Question: What makes space so cold?

Roan Haggar answered on 16 Feb 2021:

That’s a good question! Basically, space is cold because there’s no sources of heat in space. On Earth, you can feel heat coming from the Sun if you stand outside on a sunny day. But, the stuff around us also produces heat and can keep us warm. For example, at night the air is usually somewhere between 0 and 20 degrees, even when there’s no sunlight to heat it up. So, even when there’s no heat from the Sun, the temperature on Earth still isn’t too cold (compared to space!).
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In space there’s no air, and so there’s nothing else to provide warmth. If you were in space and quite near to the Sun then its heat would keep you warm (just like a sunny day on Earth). But, if you were being shaded from the Sun, or you were a long way away from it (for example, near Pluto), then there would be nothing to keep you warm at all. This is one of the reasons astronauts have to wear special suits, to stop them from freezing! Hope this helps!