How is space “cold” when it’s a vacuum? Isn’t temperature transferred between mass? If anything, shouldn’t you overheat when in a vacuum, because your body generates heat?
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Things can be very cold but almost not conduct heat. Touching metal at -100 °C can hurt a lot, and cause serious damage to the skin. Meanwhile, touching plastics is relatively fine; with aerogel, you possibly won’t even notice the cold. That is due to their low thermal conductivity, which your body can overcome. Stuff feels hot or cold when it transfers heat to or from you.
It’s the same with the vacuum of space. Stuff in space (this includes entire planets, astronauts, satellites, asteroids, you name it) cannot conduct heat away in any immediately notable manner.
However, there is another method for things to exchange temperature: light, thermal radiation in particular. Everything emits light, the hotter the more and brighter. You can feel the radiating heat of a campfire even upwind. It’s also what makes very hot objects such as molten steel, incandescent lightbulbs or the sun itself glow brightly. Even your body does so, just at a significantly lower intensity, and effectively all of it as light our eyes cannot see.
It typically takes much longer to radiate heat away as light as to conduct it. Hence your body will heat itself up. Even worse, any sunlight will also add to that. Your own light is just too weak to counter those; it only changes long after you would have boiled to death. Or you stay in the shadow of a planet, in which case stuff will slowly cool down to deep freeze.
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