I saw a science program that said the coldest spot in our solar system is on one of Neptune's moons, where it is about 3 degrees above absolute zero, "where molecules stop moving". I'm curious, is that what Temperature means--some kind of function of moving molecules? And why can't there be temps lower than absolute zero? We can go negative on the Fahrenheit and Centigrade scales--why not Kelvin's?
Originally posted by PinkFloydThe answer to the last question is simple. Celcius is defined by 0 degrees being the temperature at which water freezes and 100 degrees being the temperature at which water boils. I believe this must be at a given pressure, but I don't know what that measurement is.
I saw a science program that said the coldest spot in our solar system is on one of Neptune's moons, where it is about 3 degrees above absolute zero, "where molecules stop moving". I'm curious, is that what Temperature means--some kind of function of moving molecules? And why can't there be temps lower than absolute zero? We can go negative on the Fahrenheit and Centigrade scales--why not Kelvin's?
Fahrenheit is similar in how it determines its degrees - except it's based on a solution.
I'm pretty sure that Kelvin is defined by 0 degrees being that absolute zero temperature.
I'm also pretty sure that temperature does have a lot to do with how fast molecules move, although this is getting to where I'm very rusty in my scientific knowledge.
Originally posted by PinkFloydYes, temperature is a measure of the average kinetic energy of the particles that make up an object, atmosphere or whatever. At absolute zero there is no movement of particles. There's no such think as "negative movement" because temperature ignores direction of motion.
I saw a science program that said the coldest spot in our solar system is on one of Neptune's moons, where it is about 3 degrees above absolute zero, "where molecules stop moving". I'm curious, is that what Temperature means--some kind of function of moving molecules? And why can't there be temps lower than absolute zero? We can go negative on the Fahrenheit and Centigrade scales--why not Kelvin's?
Other temperature scales set their zero at a point where there's still kinetic energy in the particles, so less kinetic energy makes sense.
Originally posted by AThousandYoungThank you.
Yes, temperature is a measure of the average kinetic energy of the particles that make up an object, atmosphere or whatever. At absolute zero there is no movement of particles. There's no such think as "negative movement" because temperature ignores direction of motion.
Other temperature scales set their zero at a point where there's still kinetic energy in the particles, so less kinetic energy makes sense.
Originally posted by PsychoPawnTechnically (pedant alert) this is no longer true. Nowadays the Celsius scale is defined by absolute zero being -273.15 degrees, and the triple point of water being 0.01 degrees.
Celcius is defined by 0 degrees being the temperature at which water freezes and 100 degrees being the temperature at which water boils.
🙂
(The triple point is the only temperature at which water can exist as solid, liquid and gas phases in thermodynamic equilibrium)
Originally posted by mtthwAnd even if something could achieve absolute zero, there is still energy in the system due to quantum uncertainty so even absolute zero does not mean totally zero energy.
Technically (pedant alert) this is no longer true. Nowadays the Celsius scale is defined by absolute zero being -273.15 degrees, and the triple point of water being 0.01 degrees.
🙂
(The triple point is the only temperature at which water can exist as solid, liquid and gas phases in thermodynamic equilibrium)
Originally posted by PinkFloydI think one of the coldest spots in the solar system is Triton and Pluto, both at about -391 degrees F. I think thats about 30 degrees Kelvin, not 3 degrees. The Cosmic Background Radiation comes in at about 2.7 degrees Kelvin so it seems to me nothing in the universe (unaided by machinery) can get to 3 K. BTW, Triton has liquid nitrogen (!) Volcanoes!
I saw a science program that said the coldest spot in our solar system is on one of Neptune's moons, where it is about 3 degrees above absolute zero, "where molecules stop moving". I'm curious, is that what Temperature means--some kind of function of moving molecules? And why can't there be temps lower than absolute zero? We can go negative on the Fahrenheit and Centigrade scales--why not Kelvin's?
Originally posted by FabianFnasWhy do you know so much about that scientific stuff ?? Do you study physics ?
The coldest spot in the solar system, perhaps the coldest spot in universe is at cryolaboratories on Earth. Only milli-kelvins (mikro- ? nano- ?) from the absolute zero point.
In the deepest space, between galaxies, there is only 3 Kelvin. Quite hot in comparison.
Originally posted by FabianFnasI thought Thatcher was the coldest point in the universe.
The coldest spot in the solar system, perhaps the coldest spot in universe is at cryolaboratories on Earth. Only milli-kelvins (mikro- ? nano- ?) from the absolute zero point.
In the deepest space, between galaxies, there is only 3 Kelvin. Quite hot in comparison.
Originally posted by FabianFnasNanokelvin, and working on picokelvin. The latest, a magnetic trap double laser cooler, called the Picokelvinator🙂
The coldest spot in the solar system, perhaps the coldest spot in universe is at cryolaboratories on Earth. Only milli-kelvins (mikro- ? nano- ?) from the absolute zero point.
In the deepest space, between galaxies, there is only 3 Kelvin. Quite hot in comparison.
Originally posted by sonhouseHave you ever heard of the casimir effect?
And even if something could achieve absolute zero, there is still energy in the system due to quantum uncertainty so even absolute zero does not mean totally zero energy.
Theoretically it can produce negative mass/energy etc (lower than the random quantum fluctuations). We might need a few more years than we have got to find out much about that though!
Originally posted by ivan2908Thank you for the compliment.
Why do you know so much about that scientific stuff ?? Do you study physics ?
I have a deep interest of natural science in general, astronomy in specifics. But I don't longer study it in organized form, but I read scientific magazines, search on internet, discuss, and attend lectures when/where I can.
Science is simply fun!
Originally posted by flexmoreYes, I have heard and read about the Casimir effect and we are actively studying it right now. It seems in nanomachines, like nanosized gears, the casimir effect has a detrimental action on the friction-like activity, called 'stiction'. The casimir effect was proven to be real only recently but now we can see it in nanomachines, it bolluxes up gears by attracting teeth together with an extra force that has to be overcome, in addition to the regular magnetic and electric field forces.
Have you ever heard of the casimir effect?
Theoretically it can produce negative mass/energy etc (lower than the random quantum fluctuations). We might need a few more years than we have got to find out much about that though!