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human
ELI5: If heat travels in space, why do we think things close to the Sun still freeze?

I'm reading Apollo 13, and they keep talking about how they need to be careful of the Sun overheating their ship on the way to the Moon. But in so many movies and media, it all shows people/objects/water freezing in the vacuum of space. Why does the ship need to be protected if things are freezing?

Edit: I think I get it - radiation causes things in view of the Sun to still heat up, and things not facing the sun freeze in the vacuum. 

With liquids in a vacuum, they boil, giving off heat until they have no heat left, and then they freeze. A person would do the same - our body would try to exert as much heat as possible, which would cause us to overheat, but then we'd run out of heat, and freeze. If any part of us was close to the Sun (like how close the Earth or Moon is), that would also overheat due to radiation, and burn. Is that right?
gpt
What travels through space is electromagnetic energy. Visible light, heat (infrared), radio waves, microwaves, x-rays, gamma rays...all of these are different kinds of electromagnetic energy. 

A ship in space near Earth will get hot from the sunlight just like stuff on earth gets hot when you leave it out in the sun. The object absorbs the energy coming from the sun and it becomes heat (infrared).

But here's the tricky thing. Here on earth, we see that hot objects will cool down pretty quickly if you just leave it in a cooler place. The heat leaves as both infrared radiation (like if you hold your hand close to something hot and feel its warmth, that's infrared), and also through conduction into other things. Everything is surrounded by air which will take in some heat, and so will the surface that the hot thing sits on (like when a hot mug of tea makes the table warm.)

In space, there is no air or table. So the ship still radiates infrared like anything else, but but it can't also conduct heat away into other stuff. As long as the ship is fairly close to the sun, it will need to use reflectors and rotating parts to keep to stay cool. 

But the farther you go from the sun, the weaker its energy is. At some point, the ship will radiate out its heat faster than the sun warms it. So in this case, the ship will need a source of heat on board to compensate.

Without an internal heat source, anything that loses heat faster than it gets warmed by the sun will indeed freeze.