(meteorobs) Observation December 13/14 2012 (Geminids adventure part II)

Thu Jan 17 01:21:33 EST 2013

Just a small correction to the following paragraph at the end of my report; should read the following:

"In the two nights combined, I recorded 989 meteors (of which 839 were Geminids) not including the many seen during breaks.  I also photographed 220 Geminids.  Overall, this ranks as my favourite Geminids return!  Raymond and I packed up and left later that day.  1200km later, we were home."

Cheers,
Pierre

On 2013-01-16, at 12:49 AM, Pierre Martin <pmartin at teksavvy.com> wrote:

> Geminids adventure part II
> 
> 
> On the next day, Raymond and I got concerned when we saw the deep blue sky filling up with cirrus late in the afternoon.  Where did it come from?  The weather should be perfect, and we really didn't want to miss out on the Geminids peak night.  This prompted Raymond to switch on his satellite phone and connect it as a modem with his tablet PC so that he could access internet.  We pulled up the latest CSC and it continued to show excellent observing conditions for the night.  A phone call to a friend reassured us that the cirrus was just a small band that would be entirely gone by 8pm.  Sure enough, the sky eventually became absolutely beautiful just as the weather had promised, with stunning transparency for the entire night!  In fact, the sky was even better than the previous night, reaching mag 6.5 plus.  The stage was set!  I was especially excited about this night as the prime observing time (around 1-2am when radiant at its maximum elevation) would be occurring at a poin
> t in the Geminids activity profile known as "fireball window".  That was something that I had not yet experienced with this shower.
> 
> A special guest and a friend of Raymond joined us on this night to observe and photograph the shower.  It was John Chumack of Dayton, Ohio!  A well known name in the U.S., John is a highly experienced astro-imager who runs the Galactic Images website.  Many of his images regularly appear in popular magazines, Spaceweather.com, NASA and APOD.  The Geminids kept me busy, but I was fascinated by John's automated imaging techniques, and I also enjoyed listening in to the conversations he was having with Raymond.
> 
> I started observing as early as 7:30pm to look for Geminid earthgrazers and keep an eye out for possible 46p'ids (though none were seen).  The first Geminid that Raymond and I both saw was an 80 degrees long earthgrazer that looked like a rock skipping on the surface of water.  The rates were already quite good throughout the evening hours, despite the low radiant.  But shortly after midnight (period 4) the Geminids really kicked into high gear!!  For a good couple of hours, the rates surged to well over a Geminid per minute on average - with many instances of several meteors coming quickly in short spans of time.  The most striking thing was that they were clearly much brighter than the previous night with numerous negative mag meteors.  The "Fireball Window" manifested itself in the post-midnight hours... I recorded eleven fireball-class Geminids (one -7, one -6, one -5, three -4s and five -3s).  Plus another of mag -5 appearing to split into two pieces while I was attendin
> g my cameras.  The brightest Geminids were typically bluish or blue-green.  Raymond, John and I would often find ourselves shouting out and cheering when something big would streak by :)  A few more people came to join us; a nearby family, which happens to be members of the CAS.  They were pleasant and they enjoyed viewing the meteors with us for a while.
> 
> I was surprised at the quality of the night sky there.  Although it's in the green part of the light pollution map, I felt as though it could easily have been a level darker than that.  Even though there are a couple of small towns nearby, the glows were dim and quite unobtrusive.  Perhaps the excellent sky transparency made a difference too.
> 
> During the last period of observing (4:31-5:50am), it was obvious that the Geminids were past maximum rates and were now dropping off... fast.  During that time, I only saw 32 Geminids in an hour's teff.  Clearly, the shower was winding down just as the night was ending - talk about good timing!
> 
> By the end, I was exhausted and I had mostly lost my voice from having spoken into my tape recorder almost non-stop.  But I was absolutely thrilled with such a fantastic night!  I recorded 525 meteors (including 458 Geminids).  This shower is still, in my opinion, the finest and most reliable!
> 
> Photo results for Dec 13/14:
> 
> http://goo.gl/IUuas
> The early evening as the cirrus clouds receded to the east, single shot with 1 Geminid below Jupiter and the Hyades (the other streaks are planes), Canon 5D with Canon 15mm f/2.8 Fisheye, ISO1600, 30 sec exposure at f/2.8
> 
> http://goo.gl/0atkB
> Composite of 4 Geminids captured early in the evening, stacked digitally, Canon 7D with Canon 17-55mm f/2.8, ISO1600, 1 min exposures at f/2.8. Tracked with Vixen GPDX
> 
> http://goo.gl/PsqwR
> Composite of 98 Geminids captured between 9:00PM and 6:00AM the next morning, stacked digitally, Canon 7D with Canon 17-55mm f/2.8, ISO1600, 30 sec exposures at f/2.8 (meteors); ISO400, 4.5 min exposure at f/4.5 (star field). Tracked with Vixen GPDX.
> 
> http://goo.gl/GA9xM
> Composite of 53 Geminids captured between 9:00PM and 6:00AM the next morning, stacked digitally, Canon 5D with Canon 50mm f/1.4, ISO1600, 25 sec exposures at f/2.0 (meteors); ISO800, 4.5 min exposure at f/4.5 (star field). Tracked with Vixen GPDX
> 
> http://goo.gl/2s51c
> A late night Geminid between Orion and Jupiter. Single shot, Canon 5D with Canon 50mm f/1.4, ISO1600, 25 sec exposure at f/2.8
> 
> Here's two animations of multiple frames showing bright geminids leaving persistent trains seen twisting and drifting across the sky.  Be sure to wait for the Animated GIFs to load completely, then it will loop.  Visually, the trains were visible only a few seconds, but the camera captured them for much longer than that:
> 
> http://goo.gl/i2FVn
> (series of exposures spanning 7 minutes. Note the group of satellites all moving slowly together (geo sats?)
> 
> http://goo.gl/Uxnl5
> (series of exposures spanning 3 minutes)
> 
> My formal report:
> 
> Dec 13/14 2012 00:30-10:50 UT (19:30-05:50 EST)
> Breaks (lots of breaks to attend cameras or late-night snacks): 00:38-44, 01:36-02:30, 02:43-45, 02:53-03:01, 04:30-05:21, 06:49:53, 07:29-32, 07:45-08:28, 08:31-34, 10:16(30sec), 10:20(20sec), 10:22:37 UT
> Location: Cincinnati Dark Sky Site, Peebles, Ohio, U.S.A
> (Long: 83 deg 27' 35" W; Lat: 38 deg 52' 32")
> 
> Observed showers and radiant position:
> Geminids (GEM) - 07:28 (112) +32
> Antihelion (ANT) - 06:12 (093) +23
> Monocerotids (MON) - 06:48 (102) +08
> Sigma Hydrids (HYD) - 08:16 (129) +02
> December Leonis Minorids (DLM) - 10:22 (155) +34
> Coma Berenicids (COM) - 11:30 (172) +19
> December Alpha Draconids (DAD) - 14:00 (210) +58
> 
> Period 1:
> 00:30-01:36 UT; clear; F 1.00; LM 6.40; facing E 50 deg; teff 1.00 hr.
> GEM: thirty-seven: -2; -1(5); 0(4); +1(7); +2(4); +3(5); +4(10); +5(1); mean: +1.83
> ANT: two: +3(2)
> Sporadics: five: +2; +3(2); +4(2); mean: +3.2
> Total meteors: forty-four
> 
> Period 2:
> 02:30-03:40 UT; clear; F 1.00; LM 6.42; facing SE 50 deg; teff 1.00 hr.
> GEM: sixty-five: -2(2); -1(7); 0(11); +1(10); +2(10); +3(10), +4(11), +5(4); mean: +1.74
> MON: two: +2(2)
> Sporadics: two: +4; +5; mean: +4.5
> Total meteors: sixty-nine
> 
> Period 3:
> 03:40-04:30 UT; clear; F 1.00; LM 6.45; facing SE 50 deg; teff 0.83 hr.
> GEM: sixty-five: -2; -1(7); 0(5); +1(6); +2(12); +3(18); +4(14); +5(2); mean: +2.17
> MON: one: +3
> Sporadics: three: 0; +3; +5; mean: +2.66
> Total meteors: sixty-nine
> 
> Period 4:
> 05:21-06:21 UT; clear; F 1.00; LM 6.50; facing SE 50 deg; teff 1.00 hr.
> GEM: eighty-five: -3(2); -2(3); -1(8); 0(8); +1(5); +2(16); +3(18); +4(16); +5(9); mean: +2.11
> MON: two: -2; +5; mean: +1.5
> HYD: two: +3(2)
> ANT: one: +4
> COM: one: +2
> Sporadics: five: +2(2); +3; +4(2); mean: +3
> Total meteors: ninety-six
> 
> Period 5:
> 06:21-07:25 UT; clear; F 1.00; LM 6.53; facing SE 50 deg; teff 1.00 hr.
> GEM: eighty-six: -5; -4; -3(2); -2(3); -1(6); 0(12); +1(10); +2(16); +3(11); +4(17); +5(7); mean: +1.75
> MON: two: +4(2)
> ANT: one: +5
> DLM: one: +4
> COM: one: -2
> Sporadics: ten: -1; +1; +3(3); +4(3); +5(2); mean: +3.1
> Total meteors: one-hundred-one
> 
> Period 6:
> 07:25-07:45 UT; clear; F 1.00; LM 6.53; facing SE 50 deg; teff 0.283 hr. (short period due to breaks)
> GEM: seventeen: -6; -2; -1; 0(2); +1(2); +2(2); +3(5); +4(2); +5; mean: +1.47
> HYD: one: +3
> Sporadics: three: +2; +3; +4; mean: +3
> Total meteors: twenty-one
> 
> Period 7:
> 08:28-09:31 UT; clear; F 1.00; LM 6.53; facing SW 50 deg; teff 1.00 hr.
> GEM: seventy-one: -7; -4; -3; -2(2); -1(6); 0(7); +1(10) +2(9); +3(15); +4(13); +5(6); mean: +1.84
> HYD: two: +1; +4; mean: +2.5
> ANT: one: +4
> MON: one: +4
> DLM: one: -1
> COM: one: +3
> Sporadics: four: +2(2); +3; +4; mean: +2.75
> Total meteors: eighty-one
> 
> Period 8:
> 09:31-10:50 UT; clear; F 1.00; LM 6.53; facing SW 50 deg; teff 1.05 hr.
> GEM: thirty-two: -4; -2(2); -1; 0(4); +1(4); +2(9); +3(5); +4(5); +5(1); mean: +1.65
> COM: two: 0; +2; mean: +1
> Sporadics: ten: +1; +2; +3(3); +4(2); +5(3); mean: +3.5
> Total meteors: forty-four
> 
> 
> In the two nights combined, I recorded 989 Geminids (not including the many seen during breaks) and photographed 220 of them.  Overall, this ranks as my favourite Geminids return!  Raymond and I packed up and left later that day.  1200km later, we were home.
> 
> All in all, a wonderful road trip and observing adventure!  
> 
> Clear skies,
> 
> Pierre Martin
> Ottawa, Canada
> 
> 
> 
> 
> 
> 
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