Heat can be transmitted by radiationThat's how it gets from the Sun to us, so for the thermometer experiment, it would slowly reach the temperature of it's surroundings, but it would be pretty slow as the only transmission of heat would be radiation.
Anyway, the 3K microwave background is actually called that because it has the spectrum of a black body at 3K, it doesn't necessarily imply that space is at 3K.
Because of the lack of pressure, any moisture on the surface of your body would pretty instantly vapourise - this would extract a lot of heat energy from surrounding tissues, so if you had your eyes open then they'd probably start freezing pretty quick. But it would be a race to see whether they'd explode out of your head due to the pressure gradient first.
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Tue 30 Dec 2008, 11:01,
archived)
Anyway, the 3K microwave background is actually called that because it has the spectrum of a black body at 3K, it doesn't necessarily imply that space is at 3K.
Because of the lack of pressure, any moisture on the surface of your body would pretty instantly vapourise - this would extract a lot of heat energy from surrounding tissues, so if you had your eyes open then they'd probably start freezing pretty quick. But it would be a race to see whether they'd explode out of your head due to the pressure gradient first.