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(meteorobs) Re: Meteor Hunt of November 19/20, 2003!
Mark and All,
Here are answers to your questions and a few suggestions:
1:15am EST is not too early for the Leonids as the radiant should be 25-30
degrees in elevation. Granted you will normally see more activity when the
radiant is higher but with the numerous predictions of enhanced activity one
should view as soon as the radiant clears the horizon.
Your "outdated" radiant coordinates were probably close unless they were a
week old or more.
A shower member can appear at any distance from a radiant, even zero (point
meteor). The key is the length of the path. A long meteor cannot appear near
its radiant. A general rule is that a meteor cannot appear less than twice
its path length from its radiant. Therefore a meteor five degrees long must
appear at least ten degrees away from its radiant in order to be considered
a shower member.
Odds are on November 20 the three meteors you saw coming from inside the
"sickle" were indeed Leonids. If they appeared to come from an area to the
north of the "sickle" then I would have called them members of the northern
apex radiant.
A fifty percent obstruction is pretty high and involves a large correction
factor. I would suggest making the top of the trees the bottom of you field
of view so that no actual blockage of your field of view occurs. Obstruction
also implies that you cannot see through it which is not the case for thin
clouds. I would suggest making magnitude estimates every fifteen minutes to
more accurately reflect your observing conditions. If you would follow these
suggestions then you would list no obstructions and a variable limiting
magnitude throughout your session.
I would like to hear more about your portable "atomic clock". I may have to
trade in my talking clock for one of these (if they are not too expensive)!
I hope this helps!
Bob Lunsford
----- Original Message -----
From: "Mark Fox" <unclefireballmtf@yahoo.com>
To: <Meteorobs@meteorobs.org>
Sent: Tuesday, November 25, 2003 11:22 AM
Subject: (meteorobs) Meteor Hunt of November 19/20, 2003!
> November 25, 2003
>
> Greetings Meteor Enthusiasts!
>
> I'm sorry for the late report, but this one was my
> second biggest that I ever typed.
>
> It looked promising on Tuesday for doing some post
> Leonid observations on the night of 19/20. Thus, I
> did some "sample" hunting from 8:14:30 - 8:24:30 PM
> EST to see how things looked, under a clear sky of
> about 5.4 LM. No meteors. Then, rather early in the
> night, I woke up for the big hunt. However, only
> when I got dressed did I realize I had read my watch
> wrong. ~1:15 PM EST was a bit early for the Leonids I
> thought. Still, I decided to start observing.
>
> In almost an hour of hunting I "bagged" 13 meteors, an
> amazing number for me. Most were sporadics, with
> possibly three Leonids. As I mentioned before, I
> fumbled a lot during the hunt, and feel uncertain if
> the data I compiled is as accurate as it may look, due
> also to the slightly outdated radiant coordinates I
> used. I feel the magnitudes of the meteors, for
> instance, could be a little on the dim side if any are
> off.
>
> In regards to the possible Leonids I saw:
>
> 1. I have forgotten how many degrees between a meteor
> radiant and the path of a meteor for one to be a
> shower member. Was it twice the path length of a
> meteor? The possible 20 deg. Leonid that produced
> the 1 sec. train started somewhere around 20 deg. from
> the radiant.
>
> 2. Also, since the "NPX radiant" was active near the
> Leonid radiant, but at a lower rate, is it safe to
> label the three possible Leonids as Leonids? All were
> traced back to the "sickle area". Are there any
> further distinguishing marks that can be employed in
> telling apart Northern Apex meteors from Leonids?
>
> Like always, I appreciate any comments or corrections
> with the report that begins now:
>
>
> DATE: November 19/20, 2003 BEGIN: 6:50 UT
> END: 7:53 UT
> OBSERVER: Mark Fox
> LOCATION: Long: 85 deg. 49' W; Lat.: 43 deg. 27' N
> City & State: Newaygo, Newaygo, Co., MI USA
> Elevation: 762 feet (observed by our lake shore)
> Start Temperature: 38 F (03 C) @ 6:43 UT
> End Temperature: 37 F (03 C) @ 7:56 UT
> Wind: Calm.
> RECORDING METHOD: Designate Tape Recorder or Manual:
> manual (paper & pencil) + a traveling atomic clock
> -----------------------------------------------------
>
> OBSERVED SHOWERS: (Use 3 letter Codes)
> LEO
> NPX
> AMO
> SPO
> -----------------------------------------------------
>
> LEO RADIANT HEIGHT: about 35-40. deg. (At start of
> session.)
> -----------------------------------------------------
>
> OBSERVING PERIODS:
> (On average, 10 sec/meteor should be subtracted for
> recording purposes.)
> 0 = None seen; / = shower not watched.
>
> PERIOD(UT) FIELD LM TEFF LEO NPX AMO SPO
> 6:50-7:53 *RA 07 39 18.1 ~5.4 0.95 3? 0 0 10
> Dec +05 13 30
>
> *Note: This area is where alpha Canis Minoris
> (Procyon) is located. However, I also monitored
> the Orion and Canis Major regions closely at times.
> -----------------------------------------------------
>
> MAGNITUDE DISTRIBUTIONS:
>
>
> SHOWER -2 -1 0 +0.5 +1 +1.5 +2 +3 +4 +5
> LEO 0 0 2 0 0 0 0 1 0 0
> NPX 0 0 0 0 0 0 0 0 0 0
> AMO 0 0 0 0 0 0 0 0 0 0
> SPO 0 1 0 1 3 1 2 1 0 1
>
> Total: 13 meteors
> -----------------------------------------------------
>
>
> FIELD OF VIEW OBSCURED:
>
> ~50% FROM: 6:50 UT
> TO: 7:53 UT
>
> Note: The above was due to tree obstructions and
> haze/thin clouds. ~15 deg. above the horizon (of my
> field of view) were obscured by haze throughout my
> observations. Thin clouds started to become annoying
> at the end of my session, but overall, I think the
> obstructions on average were ~50%.
> ----------------------------------------------------
>
> DEAD TIME: ~ 6 min.
>
> BREAKS: none
> -----------------------------------------------------
>
> LIMITING MAGNITUDE:
>
> AVERAGE
> STAR STAR
> TIME AREA COUNT LM
>
> 0:32:00 4 7+ 5.1+
> 0:37:00 8 9 5.5
> 0:40:00 4 7+ 5.1+
> 1:00:00 8 ~10 5.9
> 1:00:00 4 ~8 ~5.3
> 1:00:00 9 6 -
>
> MEAN LIMITING MAGNITUDE: ~5.4
> ----------------------------------------------------
>
> METEOR DATA:
>
>
> SPEED
> # TIME(UT) SHOWER MAG (1-5) COLOR TRAIN(SEC)
> -----------------------------------------------------
> 1 6:54:18 SPO ~2 5 Wh. -
> 2 6:58:30 SPO? -1 3 Wh. -
> 3 7:02:27 SPO 2 3 Yel. -
> 4 7:08:57 SPO 1 5 - -
> 5 7:16:17 SPO 3 5 Red -
> 6 7:19 SPO 1 3 Wh. -
> 7 7:23:35 SPO 5 - - -
> 8 7:33:00 LEO? 0+ 5 Wh. 1 (Wh.)
> 9 7:33:30 SPO ~1 ~3 - -
> 10 7:36:30 SPO 0.5 - Wh. -
> 11 7:39:20 SPO ~ 1.5 - Wh./Yel. -
> 12 7:43:55 LEO? 0 3 Yel. -
> 13 (7:56:28) LEO? 3 5 Yel. -
> -----------------------------------------------------
>
>
> PATH GENERAL LOCATION
> # SHOWER LENGTH (and/or START
> & END POINTS)
>
> 1 SPO 10+ deg. ~Gem.
>
> 2 SPO? 20 deg. CMa; SE
>
> 3 SPO ~5 deg. Head of Leo; E-SE?
>
> 4 SPO 15 deg. Same as before.
>
> 5 SPO 10 deg. Near Ori.'s belt; S
>
> 6 SPO ~12 deg. Passed by beta Orionis; S
>
> 7 SPO 2 deg. Between Gem. & top of Ori.; E
>
> 8 LEO? ~20 deg. Between the two dogs; SW
>
> 9 SPO ~10 deg. -
>
> 10 SPO 12 deg. Sliced through Leo; E
>
> 11 SPO ~10 deg. -
>
> 12 LEO? 12 deg. Under CMa; S
>
> 13 LEO? ~12 deg. CMi; SW
> -----------------------------------------------------
>
> # SHOWER "APPROXIMATE" DEGREES / SEC.
>
> 1 SPO ~15 deg./sec.
> 2 SPO? 10 deg./sec.
> 3 SPO ~7 deg./sec.
> 4 SPO ~15+ deg./sec.
> 5 SPO 15 deg./sec.
> 6 SPO ~12 deg./sec.
> 7 SPO 8? deg./sec.
> 8 LEO? ~10 deg./sec.
> 9 SPO ~10 deg./sec.
> 10 SPO 12 deg./sec.
> 11 SPO ~10 deg./sec.
> 12 LEO? 12 deg./sec.
> 13 LEO? ~12 deg./sec.
>
>
> -----------------------------------------------------
>
> SPEED (VELOCITY) SCALE:
> 0 = Stationary
> 1 = Very Slow
> 2 = Slow
> 3 = Medium
> 4 = Fast
> 5 = Very Fast
>
> ----------------------------------------------------
> REMARKS:
>
> 1. The meteor time could be off some seconds due to my
> slow response in recording them.
>
> 2. LEO = Leonids; NPX = Northern Apex meteors; AMO =
> Alpha Monocerotids; SPO = sporadics.
>
> 3. CMa = Canis Major; CMi = Canis Minor; Ori = Orion;
> etc.
>
> 4. The meteor directions indicated in this report are
> estimates, but can be considered true north
> directions.
>
> 5. Meteor # 2 could have been a Taurid, even though it
> did seem a "tad" fast.
>
> 6. Meteor # 9 is sketchy except for the time.
>
> 7. Meteor # 13 was seen after the "official" session,
> but included in this report nonetheless.
> Is that okay?
>
> Bright and rocky Geminids!
>
> Mark Fox
> Newaygo, MI USA
>
>
>
>
>
>
>
>
>
>
>
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