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Re: (meteorobs) Re: sky measuring sticks+reentry+more



     As a "newbie" I certainly appreciate Norman's advice, with his list of
"measuring sticks" now printed out and clipped to my clipboard for use later this
week, I hope.  My meager first attempts at plotting have shown me the truth in his
words about the need to know stars down to 4rth magnitude, a major mental project
which, like learning a language, might require quite a bit of maintenance.
Personally, I have no qualms about putting down the charts and just counting for
the rest of the year.  I tend to develop a lazy streak at 3 and 4 in the morning.
    It was also nice to hear a useful definition of simultaneous meteors.  I do,
however, understand the definition of the word, in general terms, and would have
modified it (near-simultaneous) and probably given an interval (to the best of my
abilites) had the two meteors not been in the sky at the same time.  As I recall,
the meteors in question did not appear (light up) at the same time but the second
did appear before the first vanished. They simply did not "appear" (light up) at
the exact same moment. Had they at least appeared to have come from a common area,
I would have noted that, too.  I recall another pair a couple of  months ago that
did come from the same region, that seemed to be running a race, with one directly
behind the other.  These were simultaneous in Norman's definition, I believe, --
though they did not "appear" at the same time, they were at one point both visible
in the sky together.  I will, in the future, however, try to dispense with
vagarities like""for all practical purposes."  Whew!

     Over the weekend, I noticed that most of the meteors I observed were quite
faint and fast.  I plotted A-T meteors from the coordinates given by NAMN.
However, none of these were slow or even medium.  They were all rather  zippy.  Is
it possible that I have misnamed them, and that these were not A-T's, since I have
read other posters describe them as not fast?  I labeled them as SPO which
wouldn't change, but I noted them as A-T.  I certainly saw many of these speedy
guys --  but I feel I may be wrong in my designation.  Some were plotted, all were
aligned by ruler or cord back to, or near the lower left of the apex of
triangulum.
Thanks,  Kim S. Youmans



nmcleod@peganet.com wrote:

> The recent thread on measuring angles in the sky brought up some rather
> involved mechanical methods of doing the measuring.  I have used the
> following natural measuring sticks throughout my life, in degrees :
>
> Pollux - Castor  5
> head of Aquila  5
> belt of Orion  3
> Deneb - Albireo  23
> open bowl of Big Dipper  10
> pointers of Big Dipper  5
> Mizar - Alcaid  7
> W of Cassiopeia width  14
> altitude of Polaris for my location - variable
>
> That's it.  Once these are known, you don't need to rely on body parts.
> Southern hemisphere observers will need something additional that they can
> see from there.   The short distances are far more important for meteors,
> and I saw little discussion on these.  Once you reach 20-degree meteor path
> lengths, a length to the nearest 5 degrees is sufficient.  I frankly can't
> tell the difference between 39 and 40 degrees, for example, anyway.
>
> The public is unable to judge any kind of angle.  They understand  "horizon"
> all right.  The term  "overhead"  sounds like a precise term but it is
> actually vague.  An uninformed person might say a bright meteor  "passed
> overhead"  if it was as low as 65 degrees !  Just because your neck hurts
> when you look up doesn't mean you are looking at the zenith.  Try deciding
> where the zenith is just by looking up.  Then get a star chart with
> declinations on it and find out where your zenith really is.  I could be off
> by 10 degrees going by feel alone.
>
>  Any elevation between  "horizon"  and  "overhead"  the public tends to call
> "45 degrees."  That is the best-known non-right-angle angle.  Be suspicious
> any time someone reports seeing something at elevation 45.  That happened to
> me in one astronomy class ; a student saw a fireball in the north 45 degrees
> up.  I went over to his place and had him point out where he saw it --
> turned out it was only 15 degrees up !  It was below Polaris, which was 27
> degrees.  That's quite an oversight when I had discussed this in class.
>
> To plot meteors it is essential to know stars down to at least 4th
> magnitude.  There aren't enough brighter stars to work with and get any
> semblance of accurate plots.  Learning the constellations should be done
> first.  I used the Rey book, The Stars : A New Way to See Them, the best
> available, and had a good working knowledge of the sky in just four months.
> A year of just recording some meteor data along with learning constellations
> ought to be done before trying plots.   Few plots occur right between two
> stars.  Most often I have to use a couple of stars that the meteor missed by
> a degree or two to anchor the path.  I use a ruler against the sky.
>
> There was another reentry last week which Chip in Pensacola definitely saw.
> It also passed over the Tampa-St. Petersburg area and caused yet another
> ruckus on the Art Bell show with Peter Davenport.  We lost a pastor in Tampa
> to the UFO side because he saw this one, and for the first time he didn't
> know what he was seeing.  The radio principals lament the refusal of
> scientists to return telephone calls and wonder why.  They conjecture that
> scientists don't know what it was either, that secrets are being withheld
> from the public, and that we are being lied to.  I can help them out : calls
> aren't returned because Mr. Davenport won't believe scientists anyway hence
> they know not to waste their time with him.  I found that out for myself two
> years ago with the Seattle reentry ; nothing I said was accepted.  We can
> reach people numbered in the hundreds with rational scientific discussion,
> but Art Bell reaches millions with grossly and willfully  ignorant
> discussion, outnumbering us by 10000 to 1.  I still haven't seen one of
> these spectacular reentries and this latest one missed me by only a hundred
> miles, plus it was mostly cloudy here.
>
> On Aug 19 GWG wrote :
>
> > In Norman's case, his glasses may allow him to see 7th
> >magnitude stars, but restrict his field of view; thus making the
> [perception] correction
> >inaccurate for him. For most others, the correction probably works just fine.
>
> My glasses have a field of view 140 degrees wide and 110 degrees vertical.
> I see so few meteors near or beyond the frames that I don't consider them to
> be any restriction.  I have always gone after the largest lenses possible.
> That was a bit hard in the late 60's when small lenses became fashionable,
> some little more than slits.  Then big lenses returned by the early 70's,
> and since then plenty of very big ones have been available.
>
> On July 11 Kim wrote :
>
> >Meteors 14 and 13 were, for all practical purposes,
> >simultaneous, with 14 occuring immediatly after the
> >appearance of 13.
>
> A strict definition of  "simultaneous"  needs to be observed, that is, both
> meteors had to be visible together  for any noticeable portion of their
> appearances.  If any break between them occurs, or if one starts just as the
> other ends, then they are not simultaneous.  I have noted all occurrences of
> simultaneous meteors from my beginning.  Probably the easiest way to see two
> at once is to have a slow one in progress, then have a fast one flash into
> view.  Many times I have noted a beginner or casual Perseid observer saying
> "several were visible at once,"  when he meant to say  "several were visible
> in quick succession."  There have been only six times in 39 years when I saw
> three simultaneous meteors, and I have never seen four.
>
> In Chris Crawford's group setup, will meteor data be recorded?  I hope
> individual rates will be produced rather than an attempt to find how many
> unique meteors appeared.  The latter can't be used for comparison with
> individuals.
>
> We got by without any problem from Floyd.  Tomorrow night I would expect to
> be clear.  What sky I could see yesterday was free of haze.
>
> Norman
>
> Norman W. McLeod III
> Asst Visual Program Coordinator
> American Meteor Society
>
> Fort Myers, Florida
> nmcleod@peganet.com
>
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