RadioBanter - View Single Post - No antennae radiate all the power fed to them!

rickman · November 3rd 14, 08:41 PM posted to rec.radio.amateur.antenna

On 11/3/2014 3:09 PM, wrote:
rickman wrote:
On 11/3/2014 1:07 PM, wrote:
rickman wrote:
On 11/2/2014 4:11 PM, wrote:
Lostgallifreyan wrote:
wrote in news
The only external heat source in space is the Sun; solution, sun shade.

Maybe not. I just did a bit of Googling for 'superconductors in space' minus
quotes. There's a lot of statements abotu space missions ended because
required helium or hydrogen coolant ran out,

Yeah, the coolent ran out for the things that GENERATE a lot of heat
and need to be cooled more than radiation can provide. Radiative cooling
does not provide for a lot of cooling.

and also of space having latent
temperatures up to 100K, so a sun shade won't help a lot there with current
materials.

There really is no such thing as temperature in space as it is a vacuum.

That is a gross oversimplification. The temperature of space is the
temperature of the background radiation, even in a near vacuum.

That is also an simplification.

But not a gross oversimplification.

True.

Shall we go into why an ordinary thermometer exposed to the Sun at about
Earth's distance from the Sun allowed to stabilze will read the
tempurature of space as about 7 C and what are the unstated assumptions
for this to happen?

The number I found was about 4 °C. I believe it was posted with all the
assumptions...

--

Rick