Temperature in a vacume

[RTFishall]

If the vacuum of space is nothing, how can it have a temperature and if it has, how can it be measured?

[jadyn]

http://www.newton.dep.anl.gov/askasci/chem03/c hem03305.htm

[jadyn]

http://www.madsci.org/posts/archives/2005-05/1 117199358.Ch.r.html

[gen2]

I would take issue with much of both of those answers linked to above.

In both cases the thermometer is reading the temperature of the thermometer itself when separated from its surroundings by a vacuum. The thermometer is NOT measuring the temperature of the vacuum. A vacuum does not have a temperature - it is NOT absolute zero, it is NOT room temperature, and it is NOT any other specified temperature.

In a vacuum, the perceived temperature depends upon the reletionship between radiation absorbed and radiation emitted.

[jadyn]

Fascinating. As I understand, both the links provided were from people working in higher education in american universities.

Would you consider yourself on on par with their knowledge, expertise and experience gen2? Can you substantiate your statement?

[New Judge]

The bigger issue to grasp here is that space (even inter-stellar space) is never a complete vacuum. There are always odd particles here and there and they will have energy which will take the temperature (however measured) above absolute zero.

[Tom Braider]

I'm sure gen2 could substantiate her statement, jadyn. It's axiomatic that in the complete absence of matter there can be no temperature. But that doesn't make your sources wrong; it's just a matter of how you phrase the question. To say that the vacuum of space has no temperature is true but it's not the whole story; you need to know about what happens to the temperature of a body in that vacuum (and to know that space isn't a perfect vacuum) to get the whole picture.