(meteorobs) Observation November 16/17 2009 + images

Tue Dec 8 23:06:05 EST 2009

Here's my belated report on the Leonid meteor shower:

What a great night!!  I had the pleasure of spending the entire night  
at Bootland Farm (located west of Ottawa), under crystal clear skies  
for the peak night.  I was among a lot of company.  In fact, it was a  
surprisingly well attended night with 9 cars in the observing field,  
despite it being a weeknight.  Half of those present had telescopes  
setup and the other half had come to join me for observing/ 
photographing the Leonids.  Four of us managed to pull an all-nighter,  
staying up observing until 6AM!  (That was fun!)  Overhead, the skies  
were excellent with very good transparency and stars down to mag 6.5  
at the zenith.  Only the last hour had declining limiting magnitude  
due to morning twilight.  The long night of observing was a pleasure  
in that the ground conditions were surprisingly dry for most of the  
night, thanks to a very light breeze that kept the air in movement.   
It wasn't until nearly the end of the night that we felt a layer of  
frost settling down.  All in all, a very comfortable night that went  
down just below freezing.

Just minutes from my arrival at Bootland Farm, driving along Flat  
Rapids Road, I witnessed, at precisely 8:58PM EST a truly amazing  
sight... A magnitude -8 slow moving earthgrazing sporadic fireball!!!   
The meteor gradually swelled up and took several seconds to travel  
along a nearly horizontal line from south-west to west, changing from  
blue to orange, before fragmenting spectacularly into several pieces.   
I was so taken by this sight that I am surprised I managed to keep my  
car under control.  This meteor definitely had a relatively shallow  
angle and I wouldn't be surprised if meteorite fragments were dropped  
somewhere just south of Algonquin Park (based on my rather crude  
visual sighting from inside a moving car and from studying an  
astrophotographer's lucky image of the same meteor captured about  
200km south-west of my location).  Unfortunately, my attempt to locate  
more images to provide the folks at the University of Western Ontario  
a chance to maybe do a more precise analysis on this has not been  
fruitful yet.  Upon my arrival at Bootland Farm, I was greeted by  
excited observers who had all witnessed the amazing meteor!

I took my time setting up my equatorial mount, cameras and  
accessories, ensuring that everything worked.  I shared my mount with  
Ivo's camera, so we were running three Digital SLR's together, all  
with wide angle lenses.  Although dew was not an issue yet, I opted  
not to take any chances, learning from past experience that dew/frost  
will almost always appear at some point in the night.   Our anti-dew  
system was crude but cheap and effective... chemical hand warmers in a  
sock, wrapped and taped around the lens.  The warmers provides more  
than enough heat to keep our lenses dry for several hours.

I signed just after 11pm EST, to start looking for Leonid earthgrazers  
with the radiant still hugging the horizon.  Perhaps, this was wishful  
thinking to bring back memories of the great 2001 Leonids!  For the  
next hour, I did not catch any earthgrazers but I did see two nice  
Leonids of mag 0 with fairly long 30 and 40 degrees path lengths.   
After this first hour, I took a break.

I signed "on" again at 1:27am EST.  Leonid activity was slowly  
increasing.  For the next 45 minutes, I caught 10 Leonids, as well as  
a good number of sporadics.  After that, I took another break to  
attend my cameras and grab a snack.

I got back to business at 3:00am EST.  For the next hour, the Leonids  
were quite pleasantly active with 30 of them seen.  No outbursts, but  
definitely a mild enhancement of activity.  And they were a bit on the  
bright side too.  During this hour, no less than four negative  
magnitude Leonids were seen (all -1's), as well as several mag 0 and  
+1's.  Almost all of the reasonably bright Leonids left wakes or  
persistent trains, and blue-green was a typical color.

The Leonids remained remarkably consistent all the way until dawn.   
When I signed "off" at 6am EST, I had bagged exactly 100 Leonids!   
What I saw certainly supports the experts' predictions of a plateau of  
slightly enhanced rates into the morning hours of the 17th.  Although  
no fireballs were seen while I was actively observing, I was surprised  
at the large number of mag 0 and +1 Leonids that I saw.  The average  
Leonid magnitude was over a full magnitude brighter than the average  
sporadic.

To top it off, the sporadics provided nice consistent rates.  The  
North Taurids were surprisingly active with some nice average speed  
meteors.  There was also a definite presence from the Alpha  
Monocerotids.  All in all, a very productive night!  I enjoyed the  
quiet night, the good company under dark skies, the Leonids flashing  
by and the occasional howls of the coyotes.  At the end, I was quite  
exhausted and I managed to sleep quite easily in my car until 11am!   
When I woke up, I was surprised to see another car still there...  
Turns out that Ivo had a long snooze all bundled up in his car too :)

Here's a composite image of all the Leonids captured with Canon 30D  
(ISO800) and 18mm lens at f2.8:

http://www.flickr.com/photos/13845235@N03/4116625652/sizes/o/

And the composite in the Orion region with Canon 300D (ISO800) and  
35mm lens at f2.2:

http://www.flickr.com/photos/13845235@N03/4115868249/sizes/o/

Now I'm keeping fingers and toes crossed for the upcoming Dec 13/14  
Geminids!!!  With the peak well situated for North America this year,  
I am expecting an excellent shower!

Pierre Martin
Ottawa, Ontario

DATE: November 16/17 2009
BEGIN: 04:10 UT (23:10 EDT) END: 11:00 UT (06:00 EDT)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -76 29' West; Lat: 45 23' North
Observing site: Bootland Farm, Ontario, CANADA
RECORDING METHOD: talking clock/tape recorder, cord align
----------------------------------------------------------

OBSERVED SHOWERS:_______________________________radiant position
AND (Andromedids)_______________________________01:33 +33
ERI (Omicron Eridanids)_________________________04:02 -02
NTA (North Taurids)_____________________________04:06 +23
STA (South Taurids)_____________________________04:09 +15
NOO (IMO video - November Orionids)_____________05:32 +16
AMO (Alpha Monocerotids)________________________07:28 +02
LEO (Leonids)___________________________________10:09 +23
SPO (sporadics)
----------------------------------------------------------

OBSERVING PERIODS: 0 = none seen; / = shower not observed

PERIOD(UT)___FIELD________Teff___LM____SPO_LEO_NTA_STA_AMO_AND_ERI_NOO

04:10-05:20___08:40 +64___1.17___6.40___6___2___2___1___0___0___0___0
06:27-07:13___07:29 +13___0.76___6.47___9__10___2___0___1___0___0___0
08:00-09:00___08:47 +12___1.00___6.48___9__30___2___1___1___0___0___1
09:00-10:01___09:36 +14___1.00___6.48___8__30___2___0___2___0___0___0
10:01-11:00___10:37 +14___0.92___6.06__10__28___0___0___1___0___0___0

TOTALS:___________________4.85_________42__100__8___2___5___0___0___1  
= 158

Notes: The first column (Period UT) refers to observing periods, in  
Universal Time. The second column (Field) is the area in in the sky  
where I centered my field of view. The third column (TEFF) Teff is  
simply the total time during the observing session spent actually  
watching the sky. Breaks and/or dead time are not included in the  
reported Teff. It is reported in decimal format such that a 60 minute  
observing session would be reported as Teff = 1.00.  The column (LM)  
is the average naked eye limiting magnitude seen.  All following  
columns indicate the number of meteors for each shower observed.  For  
more info, see:http://www.namnmeteors.org/guidechap2.html
------------------------

MAGNITUDE DISTRIBUTIONS:

SHOWER
______-2__-1___0__+1__+2__+3__+4__+5______AVE

SPO____0___1___1___4___2__17__10___7_____+3.16
LEO____1___4__15__21__16__15__19___9_____+2.13
NTA____0___0___1___3___0___1___1___2_____+2.50
AMO____0___0___0___0___1___1___2___1_____+3.60
STA____0___0___0___0___0___0___1___1_____+4.50
NOO____0___0___0___0___0___1___0___0_____+3.00

Notes: Magnitude -8 is comparable to a quarter moon, magnitude -4 with  
the planet Venus, magnitude -1 with the brightest star Sirius,  
magnitude +2 to +3 with most average naked eye stars and magnitude +6  
to +7 are the faintest stars the naked eye can see under typical dark  
conditions. A meteor of at least magnitude -3 is considered a fireball  
(IMO definition). The above table contains the magnitudes from all  
observed meteors, and the average (last column) for showers.
------------------------

SKY OBSCURED (FOV) (UT): None

------------------------

Dead time: 5 min (breaks)

Breaks (UT): 5:20-6:27, 7:13-8:00, 9:27-28, 10:02-06