(SNES) Friday Novemger 16; Saturday/Sunday November 17/18 == LEONIDS ==

[Les Coleman <colemans@riconnect.com>]

Hi FDO Friends and SNE Gazers

For our SNE friends, I won't normally post our logs on SNE Gazers but
the Leonids were something very special.


Friday,  November  16,  2001:    21  People.   Despite weather forecasts
calling for "mostly clear" weather, the skies at FDO this Friday started
out mostly cloudy and just got worse as the public arrived.  We expected
clearing eventually (and got it, as  you will see) but early guests  and
the staff were  very disappointed not  to be able  to do much  observing
prior to about 10 PM, when the clearing began to move in.  Staff members
included Les, Doug and Steve, and  we had several families on hand  with
children in  tow.   All we  could really  show them  was a  dim look  at
Saturn, seen through clouds so thick that the planet was often invisible
to the naked eye.  But  first timers were impressed nonetheless as  even
under the worst conditions, the ringed planet shows its stuff!

During occasional patches of partial clearing  we did get a peak at  the
globular M2 (barely) and the fine  bright double star Zeta Aquarii.   We
had hoped to  show the public  comet Linear WM1,  now an easy  target in
binoculars, but  the skies  around Perseus  refused to  clear even for a
moment.  With next to nothing to see in the sky, Les had an eager  crowd
gather around  the computer  for some  fine animations  courtesy of  Sky
Chart III.  Imaginary  trips through the solar  system on the back  of a
comet and journeys to Alpha  Centauri amazed and entertained everyone  -
as we held out hope for some clearing overhead.

Just after many of the public left, we noticed that the wind was picking
up, the  temperatures were  dropping, and  the skies  were beginning  to
clear  steadily.    By  11:30  PM  it  was totally clear from horizon to
horizon,  although  the  transparency  remained  only  fair.   Those who
remained  were  treated  to  some  fine  views of Saturn, with its moons
Titan,  Rhea,  Dione,  Iapetus,  and  Enceladus.   We looked for the dim
Mimas,  near  eastern  elongation,  but  couldn't  spot  it  this night.
Jupiter was also well seen, but there were no transits to watch and  the
Great Red Spot wasn't due to come around until quite late at night.

We did eventually get a look at Comet Linear WM1, but in the still  hazy
air  it  was  not  impressive  -  no  tail  seen.  It was easy to see in
binoculars - between mag. 6.5 and 7.0, and will surely be better seen on
a clearer night.  Nearby we enjoyed a look at the open cluster  NGC1342.
While observing it, Steve and Doug noted that the true field of view  in
the 40 mm Konig is not as large as expected (by about 25% or more).   We
have noticed this before, but not thoroughly checked out the cause.   It
may be a  case of exaggerated  claims by the  manufacturer, or it  could
have something to do with the JMI electronic focuser, which sits in  the
light path and increases the  scope's effective focal length.   A little
detective work will reveal all.

With several guests still on hand  and Orion rising we turned the  scope
to the marvelous M42 - the Orion Nebula.  It was simply spectacular,  as
usual, especially with the Oxygen III filter in place.  We also observed
the much dimmer, comet shaped, M78. The outline was faint yet  distinct.
Still in Orion we checked  the 16" scope's recently recollimated  optics
with splits of  the difficult double  stars Zeta (Alnitak),  Eta Ori, 52
Ori, and 32 Ori.  The last  is the most difficult, with a separation  of
just 1.0 arc second  and magnitudes of 4.5  and 5.7.  But  the big scope
spit  it  fairly  easily  at  303  X, indicating that the collimation is
rather good.  A crowd favorite, the dazzling Rigel, was a wide and clean
split.

Doug took  a moment  to check  out open  cluster NGC2112  in Orion.  His
memory was that this is a poor  cluster in his 8" SCT, and indeed,  even
in the 16" the  cluster is not very  impressive - fairly large  in area,
with 50 or so  faint stars scattered about.   More interesting were  the
twin clusters NGC1807 and  1817, just over the  line into Taurus.   Many
brighter members  as well  as lots  of dimmer  stars superimposed on the
Milky Way background.  NGC1817 is the more attractive of the two.

Moving into Gemini Steve and Doug revisited the ever popular "Eskimo" or
"Clown Face"  planetary nebula  NGC2392.   Doug could  make out both the
Eskimo's parka  and face;  Steve could  see only  the parka.   (A little
imagination may have  helped Doug!)   Nearby the very  rich, though dim,
open cluster NGC2420 put  on quite a show  in the 16" -  over 100 stars,
though none are brighter  than magnitude 11.   In Doug's 8" SCT  this is
always a disappointing cluster - not so with the big eye at FDO!

With a Saturday all-nighter for the Leonids in mind, Steve hit the  road
at about  12:30 AM,  leaving just  Les and  Doug to  enjoy the improving
skies for a  bit longer.   Leo was rising  in the east,  so Les reclined
outside on meteor  patrol, snug as  a bug in  his sleeping bag  and lawn
chair.   During periods  of silence,  Doug suspected  that Les  may have
nodded off,  but the  occasional "WHOA!!",  or "WOW!!!!"  dispelled that
thought!  There weren't  many Leonids seen, but  the few that were  were
quite bright, some  with trails extending  well across the  sky.  Inside
the dome,  Doug killed  all the  lights for  an attempt  at the  elusive
Horsehead  Nebula.    The  first  step  is  to  carefully  identify  the
surrounding star field - which is now becoming quite familiar to several
FDOers.  Once done, you go to averted vision to see if you can spot this
very  challenging,  low  contrast  object.    With  the  40  mm   Konig,
unfiltered, Doug had no luck.  Dropping the OIII filter in darkened  the
overall view, as expected, but there  was still no trace of the  Horse's
head.  This attempt proves  how important a totally dry  and transparent
sky is for seeing the Horsehead.  Doug had seen it only once before, for
sure, and that was on an exceptionally dark and clear night last winter.
We'll  certainly  make  further  attempts  at  this famous object in the
coming weeks and months.

Les and Doug talked about staying longer, but with better skies in store
for Saturday  night -  to say  nothing of  some VERY  long hours  - they
decided to close up and head  out "early", locking the gate at  1:50 AM.
Leaving was  difficult, as  the skies  were still  improving.   And sure
enough, on  the way  home Doug  spotted several  bright Leonids whizzing
over his car, including a brilliant fireball just above the MA / CT line
at 3 AM.  So hopes are high for the shower peak in the predawn hours  of
Sunday AM!


A word  of thanks  to Doug  who wrote  the above.   Les  was not  at the
eyepiece much tonight as he kept vigil on the early Leonids and sporadic
meteors.

                      Leonid Meteor Shower Event

Saturday/Sunday November 17/18 70-100 people.

Comet Tempel-Tuttle has  an elongated orbited  which takes it  from just
inside the  Earth's orbit  [T-T =  0.98 AUs;  Earth =  1.00 AU]  to just
outside the orbit of Uranus [T-T  = 19.68; Uranus = 19.19 AUs].   Uranus
causes a  series of  perturbations to  T-T's orbit.   Instead of exactly
tracing  the  same  path  over  and  over,  T-T takes a series of nearby
trails.  As the Earth passes through  the orbit of the comet, we have  a
brilliant shower if Earth hits a  specific trail or a poor one  if Earth
misses them.  We could predict the showers better if this was all  there
was to the calculation  but outgassing by the  comet and the solar  wind
also have an effect of the particles that become meteors.

This year the predictions were that the northeastern United States would
be the target of several trails laid down in the 18th and 19th centuries.
Judging by the show on Sunday morning, the prediction was fine.

The sky was clear all night but not exceptionally dark.  Coma  Bernices,
the Beehive, Andromeda, and M35, M6, and M37 were instantly identifiable
to the naked  eye.  I  could make out  seven of the  Pleiades but a  few
folks said they could see another star as well.  We've been having  very
dry weather and pollution  and dust are beginning  to cause a very  thin
haze.  All in all, I rate  the sky about magnitude 6.0 and on  our scale
of 0 to  10 about a  6.5 [which is  quite good].   Upper level winds had
been bad the night  before but were quite  gentle on this evening  which
was a good thing with the temperature dropping into the upper 20s.  FRom
scattered reports across the web, FDO  may just have had about the  best
viewing in the north east.   Clouds obscured many parts of northern  New
England  and  although  Massachussetts  and  New  York had partly cloudy
conditions, we were blessed with cloudeless conditions and only a bit of
haze.

FDO members have talked about holding an all night event of Saturday and
Sunday  for  quite  some  time.    Here  and  there people showed modest
interest.  We expected that between a dozen and a score of people  would
show up.  We came closer to that many arriving per hour.  We don't  have
an exact count but  for the first time  in memory, people had  to park a
sizable distance away.   The lawn  was covered with  recliners and beach
chairs on the side  where the park trees  didn't obscure the view.   Our
best guess is that over seventy people stayed a substantial part of  the
night with maybe thirty  more come and went.   In some ways  it was more
like a party or a pot  luck supper with lots of folks  bringing goodies.
(Many  Thanks!)    Coffee,  tea,  and  cocoa  was availble in the Nature
Center.  The Nature  Center provided a warm  area for a number  of folks
who  got  chilled  by  the  subfreezing  air,  along  with a snooze area
(scarcely used) and facilities.

Most people heeded the warning and brought plenty of blankets,  sleeping
bags, heavy  clothing, jugs  of various  warm brown  beveridges and more
mittens, gloves, ear muffs and  hats than Bartholomew Cubbins.   Some of
the beach  and lawn  chairs had  seen better  days.   A shift  of weight
brought  more  than  one  to  an  ignominius  end  to  the amusement and
"helpful" comments of those in the area.

Useless events  of the  night included  renaming the  stars with English
terms that reminded one of the Latin or Arabic names.  My favorites were
"Pasture  and  Cowlicks",  "Pro  Siren",  "Poles R Us", "Alpha Hydroxy",
"Gamma Gobulin",  "Bell of  Tricks" and  "Al&Debbie's Barn".   Somehow I
doubt the IAU has much reason for concern.  And even more bizarre  cause
for concern had something to do with the adherance of a pan of  brownies
to a belt buckle.   No I won't attempt to  explain it.  It was  funny at
the time, but it certainly made no sense.

The actual meteor  shower was wonderful.   We have  no definitive count.
No one wanted to be stationed looking at constellations where the action
wasn't.   And counting  action in  the constellations  around Leo became
overwhelming.  A  not too scientific  sampling for several  minutes us a
figure in excess of 1800 per hour, but it did not include periods before
and after which were much less dramatic.  My guess is we saw  altogether
more than two thousand and less than five thousand but I won't back that
figure with more than a shrug.

Many of the meteors  were large and brilliant.   Those who attended  the
Perseids early in the  year where taken by  the fact that these  meteors
were  faster  moving  in  appearance  and  brighter  of average.  Bright
meteors  with  green/blue  tails  and  yellow/orange  globes  were   not
uncommon.  At  least a dozen  long duration meteors  left glowing trails
which faded very  slowly.  The  longest duration was  somewhat over nine
minutes.  The glow  had to be associated  with the meteor because  there
was no moonlight to cause an illumination.  One meteor appeared directly
in the  circle of  Leo's sickle.   It  was headed  directly at us and it
appeared as a bright dot rather than a streak.

Rather than trying to capture  many people's ideas about what  happened,
we  are  going  to  collect  every  message about our night watching the
Leonids and create a spot for them on the website.  More about this when
we get it up and running.

Les Coleman
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