getting hit by meteors, lightning, cars

  • Thread starter Claire Petersky
  • Start date



Bill wrote:
> Scott L wrote:
>> Bill wrote:
>>>
>>> My number was off the top of my head as I remembered it from
>>> oh,...grade school, so ooooops, sorry. There were a lot less people
>>> back in the 50's and they usually knew enough to get in out of the
>>> storm. You can get trapped in a bad spot though, as I found out when
>>> a storm hit when I was in the middle of a lake and had to get flat
>>> inside an aluminum boat. I can't argue with 200 per year given that
>>> we have almost 300 million walking around. I don't think the records
>>> were that great when I was in school????? Bill Baka

>>
>> Lying flat in the boat is more dangerous than crouching in
>> the bottom, preferably on one foot. :) The problem with
>> lying flat is that there can be quite a charge differential
>> between your head and feet, and that can generate a current
>> that will interfere with the electricity of your heartbeat.
>>
>> Lightning is one of *the* meteorological killers. I believe
>> it's exceeded only by heatwaves.

>
> Getting down inside the boat seemed like the thing to do in a sudden
> thunderstorm, especially in Minnesota or Wisconsin where they ambush
> you by rolling in over the trees. It was an aluminum boat so it should
> have been a good conductor. I wonder what the statistics say about
> being caught like that since those two states live on the tourist
> fishing vacations of people from Chicago and other big cities during
> the summer. The charge differential is what gets people under trees
> when the tree is hit, as in going up one leg, through the chest and
> heart, then down the other leg. Lightning is not to be messed with,
> fun to watch but not to be trapped in.


I'll mention that aluminium oxide (which all Al in contact with air
spontaneously and very quickly gets coated with) is an excellent
*insulator*. Don't know how much lightning cares about it or how boats
are trated, but I would suppose that getting an electrical current
through one in any normal circumstances would be rather difficult.

--
What a beautiful image - Gartner wonks piled high on a burning bush,
screaming that "maybe IIS isn't so good after all" and "our statistics
show a sudden increase in temperature."
-- Chris Rovers
 
Claire Petersky wrote:
> "Marlene Blanshay" <[email protected]> wrote in message
> news:[email protected]...
>
>>Bill wrote:
>>
>>>amakyonin wrote:
>>>
>>>
>>>
>>>>Bill wrote:
>>>>
>>>>
>>>>>Claire Petersky wrote:
>>>>>
>>>>>
>>>>>
>>>>>>What are the relative statistics for:
>>>>>>
>>>>>>Being hit by a meteor
>>>>>
>>>>>Pretty unlikely. I did hear of a car being hit by a meteor that made the
>>>>>news last year, but no people. Went through the trunk.
>>>>
>>>>Cars and houses get hit on a fairly routine basis (a least a few per
>>>>decade). There was a report of a girl in the UK who was hit on her foot
>>>>by a meteor a few years ago.
>>>>
>>>>http://news.bbc.co.uk/2/hi/uk_news/england/2218755.stm
>>>
>>>
>>>Wow!
>>>She is so lucky that most of it burned up. Any larger and she might have
>>>lost that foot. Looking at that makes me wonder if there aren't millions
>>>of
>>>little meteorites that hit every year but have so little energy that they
>>>go undetected???

>
>
>>almost certainly.. most meteors burn up in the atmosphere and by the time
>>they hit us they're the size of pebbles, which is probably why we never
>>even notice. Earth is being hit by meteors all the time.

>
>
> A kid in my daughter's elementary school did his science fair project on
> frequency of meteorites in our area. He did small rock samples around the
> neighborhood, from streambeds and such. Then he used magnetism as a way to
> try to separate out the meteorites as a first pass. Once separated, he used
> others ways to identify them as such. It turned out there were plenty. They
> mostly were very small, maybe 1/4 - 1/2 cm across, but you could see them
> under the magnifying glass, and they looked just like the examples in the
> book he had. I thought it was the best science fair project this year.
>

that's pretty cool. i remember seeing moonrocks and meteors and samples
of rock taken from the moon at the National Air and Space museum.. The
moonrocks basically looked like, well, rocks...but it was behind a
display case. The museum really is a cool place.
 
Harri Haataja wrote:

> ... aluminium oxide is an excellent
> *insulator*. Don't know how much lightning cares about it....


Considering that lightning travels hundreds of meters through the air
to get between ground and cloud, a few micrometers of it probably
doesn't matter much.

The usual advice given for above-treeline mountain hiking is to crouch
on the balls of your feet to minimize damage should you be struck by
lightning.

RFM
 
Harri Haataja wrote:
>
>
> I'll mention that aluminium oxide (which all Al in contact with air
> spontaneously and very quickly gets coated with) is an excellent
> *insulator*.


If that were true, touching the two wires of your ohmmeter to a piece
of aluminum would not produce the reading "Zero ohms." Try it.

> Don't know how much lightning cares about it or how boats
> are trated, but I would suppose that getting an electrical current
> through one in any normal circumstances would be rather difficult.


Not in the least. FWIW, the electrons to deliver this message were
pushed along through aluminum wires for much of the way. IIRC, most
cross country high tension lines are aluminum.

- Frank Krygowski
 
Fritz M wrote:

>
> Harri Haataja wrote:
>
>> ... aluminium oxide is an excellent
>> *insulator*. Don't know how much lightning cares about it....

>
> Considering that lightning travels hundreds of meters through the air
> to get between ground and cloud, a few micrometers of it probably
> doesn't matter much.


Free air arc jumping is about a million volts per meter, hence a billion
volts per kilometer. No, I don't think that little oxide layer will count.
>
> The usual advice given for above-treeline mountain hiking is to crouch
> on the balls of your feet to minimize damage should you be struck by
> lightning.


Damage to your feet? If you get hit in a crouch your muscles will shoot you
straight up or so it would seem. You are nailed either way. Crawling under
a rock seems more logical, if there are rocks.
>
> RFM


Above tree line watch out for attack snow storms too. I was on Mt. Hood in
Oregon at 10,000 feet and it went from sweat and sun to white out blizzard
in about 30 seconds.
Moral...never trust the weather.
Bill Baka
 
Claire Petersky wrote:

> "Marlene Blanshay" <[email protected]> wrote in message
> news:[email protected]...
>> Bill wrote:
>>> amakyonin wrote:
>>>
>>>
>>>>Bill wrote:
>>>>
>>>>>Claire Petersky wrote:
>>>>>
>>>>>
>>>>>>What are the relative statistics for:
>>>>>>
>>>>>>Being hit by a meteor
>>>>>
>>>>>Pretty unlikely. I did hear of a car being hit by a meteor that made
>>>>>the news last year, but no people. Went through the trunk.
>>>>
>>>>Cars and houses get hit on a fairly routine basis (a least a few per
>>>>decade). There was a report of a girl in the UK who was hit on her foot
>>>>by a meteor a few years ago.
>>>>
>>>>http://news.bbc.co.uk/2/hi/uk_news/england/2218755.stm
>>>
>>>
>>> Wow!
>>> She is so lucky that most of it burned up. Any larger and she might have
>>> lost that foot. Looking at that makes me wonder if there aren't millions
>>> of
>>> little meteorites that hit every year but have so little energy that
>>> they go undetected???

>
>> almost certainly.. most meteors burn up in the atmosphere and by the time
>> they hit us they're the size of pebbles, which is probably why we never
>> even notice. Earth is being hit by meteors all the time.

>
> A kid in my daughter's elementary school did his science fair project on
> frequency of meteorites in our area. He did small rock samples around the
> neighborhood, from streambeds and such. Then he used magnetism as a way to
> try to separate out the meteorites as a first pass.


If a magnetic rock is a sign of a meteor rock then we have plenty. I took my
grandson, 12 years old, out with a strong magnet and came back with a hand
full of small pebbles. They were all rounded by stream action so I don't
know where the road department got them.
Interesting possibilities though.

> Once separated, he
> used others ways to identify them as such. It turned out there were
> plenty. They mostly were very small, maybe 1/4 - 1/2 cm across, but you
> could see them under the magnifying glass, and they looked just like the
> examples in the book he had. I thought it was the best science fair
> project this year.
>

Keeping the kids interested is actually kind of fun, since even as an adult
you can learn from them as you teach.
Bill Baka
 
[email protected] wrote:

>Harri Haataja wrote:
>>
>> I'll mention that aluminium oxide (which all Al in contact with air
>> spontaneously and very quickly gets coated with) is an excellent
>> *insulator*.

>
>If that were true, touching the two wires of your ohmmeter to a piece
>of aluminum would not produce the reading "Zero ohms." Try it.


Well, not zero... but pretty stinkin' low. Thing is, if there's a
really nasty "crust" on the aluminum, you probably would get a much,
much higher reading if you didn't penetrate it to the base material.
That's why they outlawed aluminum house wiring... the resistance of
the oxidized bits created a lot of heat and burned down a lot of
houses.

>> Don't know how much lightning cares about it or how boats
>> are trated, but I would suppose that getting an electrical current
>> through one in any normal circumstances would be rather difficult.

>
>Not in the least. FWIW, the electrons to deliver this message were
>pushed along through aluminum wires for much of the way. IIRC, most
>cross country high tension lines are aluminum.


I'm surprised that is actually the case... it would seem to be a truly
awful choice. Much higher resistance than steel or copper, and
without the tensile strength (though its lighter weight would somewhat
offset that). I guess it's a trade-off between weight, cost and power
loss. If they can build all the towers cheaper (or use fewer of 'em)
I'm betting it works out. I wonder if it's a special alloy that
conducts electricity better than "plain ol' aluminum"?

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame
 
[email protected] wrote:
> Harri Haataja wrote:
>
>>
>>I'll mention that aluminium oxide (which all Al in contact with air
>>spontaneously and very quickly gets coated with) is an excellent
>>*insulator*.

>
>
> If that were true, touching the two wires of your ohmmeter to a piece
> of aluminum would not produce the reading "Zero ohms." Try it.
>
>
>>Don't know how much lightning cares about it or how boats
>>are trated, but I would suppose that getting an electrical current
>>through one in any normal circumstances would be rather difficult.

>
>
> Not in the least. FWIW, the electrons to deliver this message were
> pushed along through aluminum wires for much of the way. IIRC, most
> cross country high tension lines are aluminum.
>
> - Frank Krygowski
>

Around here they're all copper. Thieves fry themselves often trying to
steal it for drug money.

Arlie Cooper
 
Claire Petersky wrote:
>
> "Marlene Blanshay" <[email protected]> wrote in message
> news:[email protected]...
> > Bill wrote:
> >> amakyonin wrote:
> >>
> >>
> >>>Bill wrote:
> >>>
> >>>>Claire Petersky wrote:
> >>>>
> >>>>
> >>>>>What are the relative statistics for:
> >>>>>
> >>>>>Being hit by a meteor
> >>>>
> >>>>Pretty unlikely. I did hear of a car being hit by a meteor that made the
> >>>>news last year, but no people. Went through the trunk.
> >>>
> >>>Cars and houses get hit on a fairly routine basis (a least a few per
> >>>decade). There was a report of a girl in the UK who was hit on her foot
> >>>by a meteor a few years ago.
> >>>
> >>>http://news.bbc.co.uk/2/hi/uk_news/england/2218755.stm
> >>
> >>
> >> Wow!
> >> She is so lucky that most of it burned up. Any larger and she might have
> >> lost that foot. Looking at that makes me wonder if there aren't millions
> >> of
> >> little meteorites that hit every year but have so little energy that they
> >> go undetected???

>
> > almost certainly.. most meteors burn up in the atmosphere and by the time
> > they hit us they're the size of pebbles, which is probably why we never
> > even notice. Earth is being hit by meteors all the time.

>
> A kid in my daughter's elementary school did his science fair project on
> frequency of meteorites in our area. He did small rock samples around the
> neighborhood, from streambeds and such. Then he used magnetism as a way to
> try to separate out the meteorites as a first pass. Once separated, he used
> others ways to identify them as such. It turned out there were plenty. They
> mostly were very small, maybe 1/4 - 1/2 cm across, but you could see them
> under the magnifying glass, and they looked just like the examples in the
> book he had. I thought it was the best science fair project this year.
>
> --
> Warm Regards,


That is so cool! I did have some cool experiences as a child but with the
passing years I have come to undertsnd that there's a whole world of cool things
that never even occurred to me back then.

Having a 6" or 8" reflector telescope to haul outside, into the snow, and stare
into until I'm a popcicle is a long-time dream of mine.

--
Michael