Philosophy Now Forum

"Grandpa, grandpa!"

Grandpa: "Yes (sigh), what is it?"

Grandson: "I stumped my physics teacher today with a question he couldn't answer. I asked him what the temperature of space was, you know, the kind where there no molecules around. Maybe you can answer that one."

Can you help out Grandpa with this? (btw my physics teacher got nervous when I asked him that question).

There are high-speed particles in seemingly empty interstellar space (cosmic rays, solar wind, etc) and a few "gaseous" atoms per cubic meter. The latter are too thin to mediate energy as heat conduction, but a thermometer circa the Earth's orbit could still register several degrees above freezing via absorption of sunlight by its limited surface area. Whereas a human body with an uninsulated suit, blocked from the sun and lacking the thermally "equalivalent-plus" environment of a warm atmosphere, would quickly become cold as its inadequate generated energy dissipated away as EM waves.

Thermal radiation pervades the whole universe, especially as the Cosmic Microwave Background. Accordingly, the temperature of space in even the barest region is at least 2.725 K (or -270 Celsius; minus 455 fahrenheit).

You should probably learn to use google I think.

http://www.universetoday.com/77070/how-cold-is-space/

It's bloody cold though. Cold but because there is no part of the universe that has no energy it is always greater than 0 Kelvin (K).

If your physics teacher got nervous it's because he is not a university professor of Astrophysics and related subjects, although he should of known tbh as it's general knowledge in physics you perhaps learn pre degree, I would personally be a little embarrassed if I was teaching any level of physics and did not know this. Nervousness means someone does not know. The average temperature of space across the universe not including matter concerns such as planets and stars is very close to 0K. It's a simple question and a simple answer.

Blaggard wrote:You should probably learn to use google I think.

http://www.universetoday.com/77070/how-cold-is-space/

It's bloody cold though. Cold but because there is no part of the universe that has no energy it is always greater than 0 Kelvin (K).

If your physics teacher got nervous it's because he is not a university professor of Astrophysics and related subjects, although he should of known tbh as it's general knowledge in physics you perhaps learn pre degree, I would personally be a little embarrassed if I was teaching any level of physics and did not know this. Nervousness means someone does not know. The average temperature of space across the universe not including matter concerns such as planets and stars is very close to 0K. It's a simple question and a simple answer.

This happened in the early 70s at a community college.

PhilX

You were taught by a moron, it happens, not every teacher can teach just like not every religious preacher can preach. It's a funny old world, but some people are just shit at their jobs, are or were you shocked by such a revelation? how did it affect your education? In what way is it still doing so, since you seem to have brought it up. Clearly it's a major issue for you after 40 or so years?

Blaggard wrote:You were taught by a moron, it happens, not every teacher can teach just like not every religious preacher can preach. It's a funny old world, but some people are just shit at their jobs, are or were you shocked by such a revelation? how did it affect your education? In what way is it still doing so, since you seem to have brought it up. Clearly it's a major issue for you after 40 or so years?

Not a major issue, but it still stayed in mind after all these years. I think what may surprise people is I found errors in over half the math texts I read through, whether it be the answer key or some other part of the text. Here's something else which may be a real issue. My understanding is that for engineers and scientists, over half of what you learn will be obsolete by the time you graduate college.

PhilX

Philosophy Explorer wrote:This happened in the early 70s at a community college.

As indicated in your OP, the physics teacher seemed to be discussing heat transference in the limited context of interacting atoms and molecules. The CMB was still relatively new to the public back then (Penzias and Wilson didn't win a Nobel Prize till '78). In a mundane "you local yokels are unlikely to pursue this as a career, anyway" classroom, the peculiarities and consequences of quantum mechanics [in outer space / anywhere else] were probably likewise still as much ignored as in biology. Sample of the cautious establishment of the era: "Unlikely as it may seem, these iconoclasts spun modern physics in a new direction, forcing mainstream physicists to pay attention to the strange but exciting underpinnings of quantum theory." --Hippie days: How a handful of countercultural scientists changed the course of physics in the 1970s

To this day, energy travel and thermal measurements discussed only in terms of the kinetic / mechanistic relations of fermion matter is what is often dispensed to kids (though perhaps a more justifiable initial step for that age group): "Because hot and cold are ways of talking about how fast molecules are moving, and there are so few molecules in space, space really doesn't have any temperature at all."

Hammock said:

" ...the peculiarities and consequences of quantum mechanics [in outer space / anywhere else] were probably likewise still as much ignored as in biology."

My memory is hazy here. But I do recall another teacher back then remarking that QM was a dead subject.

PhilX

Philosophy Explorer wrote:

Blaggard wrote:You were taught by a moron, it happens, not every teacher can teach just like not every religious preacher can preach. It's a funny old world, but some people are just shit at their jobs, are or were you shocked by such a revelation? how did it affect your education? In what way is it still doing so, since you seem to have brought it up. Clearly it's a major issue for you after 40 or so years?

Not a major issue, but it still stayed in mind after all these years. I think what may surprise people is I found errors in over half the math texts I read through, whether it be the answer key or some other part of the text. Here's something else which may be a real issue. My understanding is that for engineers and scientists, over half of what you learn will be obsolete by the time you graduate college.

PhilX

Such a bad teacher. It happens.

In science these days things become obsolete within about 10 years but it does depend on the subject, if you are interested in the subject you never stop learning, if you aren't you do, and then slide past the bench mark of yester year. You have to keep up it is true. But it does sound like what you said was an appalling teacher.