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Re: [Phys-L] electricity in the atmosphere

Thanks, John, for highlighting the NOVA episode, At the Edge of Space. To me
it is one of their best in showing how scientists actually do science. None
of this phony "scientific method" stuff. I have used the full episode when I
taught our lowest level general education physics class. I have students
watch it outside of class and write a short analysis (not a summary) and
answer a set of questions about it.

My daughter is taking an intro geology course and they require the students to
know the phony scientific method: hypothesis-theory-law. I can't believe this
stuff is still taught at the university level.

On Sat, February 10, 2018 9:35 am, John Denker via Phys-l wrote:
On 02/09/2018 06:47 PM, Derek McKenzie wrote:

I particularly appreciate the number estimates, as well as the idea of
modeling the phenomenon as a spherical capacitor.

For those who want to know more about the model.....

*) Magnificent reference:
"Electricity in the Atmosphere"

If you haven't recently read the Feynman lectures cover-to-cover,
I strongly recommend it.

*) Decent introduction at the qualitative level (no equations):

*) The books by Uman are useful but even the latest "revised"
edition is 50 years out of date. I haven't seen the 700-page tome by Rakov and
Uman but I gather it is more up-to-date.

*) Sprites in the upper atmosphere were predicted in 1921
by C.T.R. Wilson but not observed until 1989, and are still a hot topic of

Longer version:

That NOVA episode gives a realistic portrayal of scientists
doing their job. In particular, ask your students how they would feel if they
spent years putting together a team and building equipment, then when the
conditions are right staying up all night and spending an additional
$100,000.00 to carry
out the mission, and coming back with ... nothing! If you don't know what that
feels like, you don't know what it's like to be a scientist.

Most remarkably, NOVA did not leave out the painful part of
the story.

A few nights later, good conditions come around again, so
they carry out the mission again, and come back with ... data. Gorgeous, highly
informative data.

Additional points to tell students:
-- Not all physics was done in the 1600s. There are still
interesting unanswered questions. -- Physics is mostly a team sport; you don't
have to be a lone genius like Galileo or Newton or Einstein to make a
contribution. -- A lot of it requires building fancy instruments and
exploiting modern technology. -- OTOH it usually doesn't require CERN-sized
teams or CERN-sized instruments. Sometimes a Gulfstream-V full
of fancy cameras will do nicely. -- There is joy at the end of the rainbow, but
you have to tolerate a lot of risk and pain before you get there. This requires
strength of character. Technical skill is not enough. -- It must be emphasized
that exploring blind alleys is part of the cost of obtaining information. A
mission that comes back with no data of the desired kind is not a mistake and
not a waste. Scientists take calculated risks, carefully balancing risk
versus reward. Don't take any more risk than necessary, or any less.

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