Coldest place in the Universe

[HQ]

http://www.smh.com.au/articles/2003/...638427695.html

"It is only one degree warmer than absolute zero, the coldest possible temperature, when atoms cease to vibrate and radiate no heat whatsoever.

What is interesting for astronomers is that the nebula is colder than the microwave radiation which pervades all of space."

[HQ]

"Man has produced yet chillier temperatures. In 1995, American researchers cooled rubidium atoms to less than 170 billionths of a degree above absolute zero."

Originally posted by HQ
"Man has produced yet chillier temperatures. In 1995, American researchers cooled rubidium atoms to less than 170 billionths of a degree above absolute zero."

FYI

At absolute zero, contrary to popular misconception, movement still goes on. IIRC, the average electron speed of atoms is still computable at 1/6th of the speed of light. Electrons do not "freeze". I once did the computation as a homework exercice.

And IIRC again, helium remains liquid. At least, the cooled liquid helium to a a few ten thousand of 0 Kelvin and it remained liquid IIRC again.

That's from the top of my head, booting up lazy neurons that did not flex their myelyn for twenty years...
The best book to learn on the topic is Thermal Physics by Reif.

It starts it's introduction to Statistical Mechanics with the fundamental example of a drunk man hanging out on a lamp post and counting how many times he walks on a given sidewalk stone as he attempts to leave the lampost.

You have no idea how much of physics rests on how a really drunk man behave...

[StuartD]

how exactly do they know just how cold it is?

Did they send someone over there with a winter jacket and say "Damn, it's cold over here" ?

[twinkley]

Hahahahaha

That was my first question too Stuart!

How do they know that its so cold? Its bazillions of miles away!

twinkley

[HQ]

Originally posted by twinkley
How do they know that its so cold? Its bazillions of miles away!

Just lick your finger and point it as close as you can to the nebula. Duh!

[HQ]

Actually, this is how it's done:

"One can say the Boomerang acts as a refrigerator," said astronomer Lars-Ake Nyman, who measured its temperature using the European Southern Observatory radio telescope in Chile. He did this by comparing signals received from carbon monoxide in the nebula with signals from the background radiation.

[twinkley]

Okay....


so then how do they measure carbon monoxide in the nebula?

A really really long thermometer??


hehehehehee

twinkley

[HQ]

...something like that!

[StuartD]

Originally posted by twinkley
Okay....


so then how do they measure carbon monoxide in the nebula?

A really really long thermometer??


hehehehehee

twinkley

I hope it's not a rectal thermometer!

[Yo Adrian]

272 degrees below zero? Ah heeeeeeeell nah...

[webgurl]

Do American's still think Canadians live in an igloo ??