Hi, This is not a matter of "theory", but rather a very practical issue for all spacecraft and astronaut space suits. Spacecraft such as the ISS have heat radiators to radiate away the extra heat of machinery, astronauts and what is being picked up by the sun's thermal radiation. That this works is demonstrated by the continued operation of the ISS. The issue is even more severe, I believe, for astronaut space suits where large scale heat radiators are impractical. If you want further information, then the NASA web pages provide ample detail.

The body loses heat by radiation, microwaves and photons.

Yeah. There are three modes of heat transfer, Conduction, convection and radiation. Of course there is no matter for the first two but the third one does not require any medium.

but sir i believe that and according to my theory is there is no medium in space then no any radiation take place, by these questions i am trying to find that what is the characteristics of medium in space and till now i got some results from this that that medium is made up of fundamental particles and also if we will try to measure their behaviour then we get the result as electron type, because i think this answer is not sufficient to answer that photon is a EM wave and it not require any medium to travell and i am trying to figure out that why this thing happens, and if we will get these answers then we will be very near to understand every process in real way.....

and i am very interested to know every process briefly from the fundamental level and which make some sense that yeah this is the reality...

Space is not nothing, but something which can be filled, by matter and by radiation - photons. From thermodynamical view it is a could bath of about 2.7 K. (The problem of space was touched even by eleatic philosophers - Melissus e.g., by Descartes, Newton, Ernst Mach, Einstein, by quantum electrodynamics etc.) Interesting question...

From an experimental viewpoint, this is essentially how asteroids cool. If we look at certain asteroids, we see that the crystal structures on finds are compatible with very low cooling rates, compatible with the theoretical predictions for the asteroid having cooled down in space under the sole influence of radiation.

Hi, This is not a matter of "theory", but rather a very practical issue for all spacecraft and astronaut space suits. Spacecraft such as the ISS have heat radiators to radiate away the extra heat of machinery, astronauts and what is being picked up by the sun's thermal radiation. That this works is demonstrated by the continued operation of the ISS. The issue is even more severe, I believe, for astronaut space suits where large scale heat radiators are impractical. If you want further information, then the NASA web pages provide ample detail.

There is a well known theory-it's called thermodynamics. Electromagnetic waves do propagate in vacuum, so that's no problem; what the problem is what else is there, beyond the body in question, since the statement that it has a finite temperature only makes sense  if there's something else. 

So it might be useful to study a textbook on thermodynamics. E.g. http://www.feynmanlectures.caltech.edu/ might be a good starting point.

I think this is no interesting problem because it is no problem...

then please tell me one thing that electromagnetic wave means particle required no medium then how electromagnetism is responsible to travel or boost the particles in space so that they can go from one place to another place...

That's part of a course in physics-for which the Feynman lectures are a good introduction. 

ok thank you

This question inspired modern approach to space. Space itself is some kind of medium through which propagate (not only) photons of radiation.

Hi,

You are absolutely right in saying that in empty space nothing happens. Empty space is an idealization which basically means you introduced a coordinate system and nothing else. There are no bodies in empty space nor interactions nor fields. In real space, there are quantized fields which can interact with your hot body removing energy.

No need for quantum effects-the description can be formulated purely classically. Temperature means that the energy of the body is known only on average. So there's a bath, of unspecified degrees of freedom, that describe the fact that the body in question is in thermal equilibrium with them. So it's nothing new that the temperature of the body won't change under these circumstances-it's been known for centuries and is taught in all courses on thermodynamics.

The hot body will radiate electromagnetic waves, very nearly

according to Black Body radiation. It does not matter if the space

is empty, enm waves can go through it.

The body will then cool down.

Bodies really do cool by radiation: the following link has some nice examples. They are not in outer space, but they do not depend on surrounding matter to work, so they are pertinent to the question.

https://en.wikipedia.org/wiki/Radiative_cooling

dr Leyraz

This wikipedia entry is an example of an awful lemma in this encyclopedia, as the heading by Wikipedia itself rightly says:

"This article includes a list of references, but its sources remain unclear because it has insufficient inline citations"

Also the lemma "thermal radiation" it is referring to in the first sentence is poor as also mentioned by Wikipedia.

As mentioned by other repliers here: it is a basic observation that all bodies at a temperature above 0 K emit radiation. Even the questioner can feel it when he faces a stove or anything heated. The problem with RG is that too many newcomers (want to) invent the wheel from ignorance

Dear Dr. ten Brink,

I do not claim the Wikipedia article to be an excellent account of the theory. But it does give concrete examples, such as ice making in India, the role of reflection in roofs, and several others, which, I hoped, might give the questioner some real world basis for the phenomenon, so that he might see that this is not merely an abstract issue involving the properties of space, but a concrete everyday effect, repeatedly used for various important practical purposes.

``The questioner can feel it when he faces a stove'': indeed, but in my opinion it is important that the questioner be informed that this is what he feels when he faces a hot stove.

dr Leyvraz

Actually I was annoyed to see this question of which I was attended as a follower of you

I repeat that this question is childish and not appropriate for ResearchGate with its subquestion

"according to my theory" what does he mean with that?

The other issue is that I get also annoyed with Wikipedia and its contributors. Some lemmas are excellent others are just noise like these ones on radiation

Harry ten Brink

If your education has exposed you to heat-loss through conduction, but not heat-loss via radiation, you might understandably develop the impression that a body cannot lose heat, unless it is in thermal contact with another body.

The rule of heat-loss via radiation is called Stefan Boltzmann's Law.