2 approaches to observing glints, quadruple glint, OBS, PPAS

Walter Nissen (dk058@cleveland.Freenet.Edu)
Tue, 1 Sep 1998 19:56:27 -0400 (EDT)

Below you will find a report of a quadruple glint.  Like the triple glint 
reported earlier, the dips between the glints were very shallow.  Also a 
late glint which was about 7.6 magnitudes brighter than the predicted 
glint; and a bright early glint.  Also, 2 more triple glints, neither so 
very shallow, and a "10 out of 11 session". 
 
I'm making OBS more rapidly than I can report them, so I have nothing 
ready (yet) about the bizarre, spectacular OBS I made on orbit 1 or 2 of 
the 19980819 launch. 
 
 
There are 2 possible approaches to observing Iridial glints. 
 
One can attempt to obtain the highest rate of return for minimal 
investment.  Don't bother with any objects which might be in a 
questionable status; nor of marginal brightness.  Available tools permit a 
high degree of optimization of this approach. 
 
On the other hand, one can more comprehensively attempt to observe 
whatever presents itself.  Include all reasonably possible objects and 
accept whatever phenomena occur, such as short, repetitive flashes, 
disappointments, big surprises, whatever.  To use this approach, accept 
faint glint predictions and locate the active region(s) of the sky, if 
any.  As the predictions below show, for my location, about 19980830 09, 
this region was about altitude 50 degrees above azimuth 230.  And I'm now 
asking for all glint predictions brighter than mag 6.  Follow all objects, 
predicted or unpredicted, in the active plane when they are anywhere near 
this region, say, within 90 or 120 degrees.  This takes somewhat more 
effort, but you see more.  Prompt adoption of my proposed nomenclature for 
the Iridia will greatly facilitate use of this approach.  More data from 
this approach may permit further optimization of tools for the first 
approach.  To evaluate the relevance of this paragraph, you may wish to 
reread it, after perusing the OBS below. 
 
 
I have noticed that, on many passes, Iridial payloads are surprisingly 
constant in magnitude during large sections of the pass.  As is fairly 
common with payloads in general, which are boxier and more shadowy than a 
sphere, sometimes there is an exaggerated phase effect, being brighter 
than expected at favorable phase angles and dimmer than expected at 
unfavorable phase angles.  Another phenomenon with which I am not so 
familiar has affected many Iridia, which were easier to pick up near the 
horizon than expected and then stayed pretty much constant up to 
culmination.  I have noticed this particularly on ascending passes 
(usually evening passes).  In the instance reported below, 19980828  907, 
the object faded steadily, as is typical of most objects, and I noted this 
with a tiny bit of surprise. 
 
 
OBS: 
 
Ir P09 62 mag 2 or 3   glint           19980827  92301.5? 
          mag 2?                       19980827  92318.6? 
          down to mag 5 or 6           19980827  92419.8? 
          intervals: 17.15 s & 61.18 s. 
 
Ir P0A 63 mag 2?  nr Algenib           19980827            later mag 5? 
 
Ir P00 64 mag 4?       glint           19980827  94206.6? 
 
Accuracy for the above times is degraded because, among other things, for 
more than half an hour, there was nothing on WWV 5 MHz, 10 MHz, nor 15 
MHz.  "Palm on forehead" time: I suppose the poor reception lately is due 
to the solar activity separately reported. 
 
 
Ir P21 33 mag 2?       glint           19980828  15804.57 
          down to mag 5?            ~20 s later 
This glint was not predicted.  I wasn't able to see the predicted glint 
from this object 5 minutes later because my building blocks the lower part 
of my Northern sky. 
 
Ir P06 72 not seen in Aur 
          mag 6 or 7  BR pi-6 Ori      19980828  823? 
 
Ir P07 73 not seen (fr El Nath to gamma Eri) 
 
Ir P08 70 not seen nr Capella          19980828  838 
          mag 7?  nr lambda Tau and beyond 
 
Ir P09 62 mag 7?  fr epsilon Per to 
          beyond Menkar                19980828  847 
 
Ir P0A 63 mag 6?  R of gamma Cet       19980828  859 
 
Ir P00 64 mag 5 or 6  R of Saturn,     19980828  907 
          then actually dimmed normally as it departed 
 
Ir P01 65 identification slightly uncertain; I had difficulty locating it, 
          then saw a bright object apparently moving along the proper track 
          mag 3?  fr A Alpheratz 
          mag 3?       glint           19980828  91647.34 
          only down to mag 4? at h = 30 in South 
 
Ir P02 66 mag 5?  BR of Alpheratz 
          brightened suddenly to 
                                mag 4? 19980828  92525.79     kept brightening 
          mag 3?       glint           19980828  92537.71 
          mag 2?       glint           19980828  92617.73 
          mag 3 or 4   glint           19980828  92713.72 
          mag 3 or 4   glint           19980828  92744.82 
          down to mag 5 or 6           19980828  92818.74 
          down to mag 7?               19980828  92855.77 
Dips between glints were only perhaps .5 mag or less, at least on one "side" 
of the curve. 
 
Ir P03 67 mag 4 or 5   glint           19980828  93539.73 
          down to mag 5?               19980828  93614.66 
          mag 4?       glint           19980828  93658.28 
          down to mag 5 or 6           19980828  93733.08 
          down to mag 7?               19980828  93809.52 
 
Ir P04 68 mag 6?  B Markab             19980828  943 
          mag 5 or 6   glint     along a line between Circlet & nr Jupiter 
          mag 6?  BL Jupiter 
 
Ir P05 74 mag 6? fr BR Markab to h=15? 19980828  952     difficult in twilight 
 
Ir P06 72 not seen B zeta Peg          19980828 1001 
 
So I looked for all 11 operating objects in plane 0, and saw 10 of them. 
 
 
Ir P05 74 mag 6? between Menkar and Saturn down to h=30?? in South 
 
Ir P06 72 mag 5.5 or 6 nr delta Cas, lost at mag 7? h=40?? in South 
 
Ir P07 73 mag 6?  B Caph 
          up to mag 5?                 19980830  90402.81 
          mag 2 or 3   glint           19980830  90442.44 
          down to mag 5?               19980830  90514.19 
          lost mag 7?                  19980830  90629.44 
 
Ir P08 70 mag 5 or 5.5 
          up to mag 5?                 19980830  91322.11 
          mag -2 or -3 glint           19980830  91353.02  naked eye 
          mag 3?       glint           19980830  91436.93 
          mag 3 or 4   glint           19980830  91528.46 
          sudden drop to mag 6?        19980830  91601.89 
          lost mag 7?                  19980830  91619.19 
 
Ir P09 62 mag 5 or 6 
          up to mag 5?                 19980830  92213.56 
          mag 4 or 5   glint           19980830  92254.95 
          mag 3 or 4   glint           19980830  92325.48 
          down to mag 5?               19980830  92351.62 
          mag -2.9?    glint           19980830  92438.19  naked eye 
          down to mag 5?               19980830  92456.18 
          lost mag 7?                  19980830  92518.54 
The naked eye OBS was made only a few degrees from mag -2.9 Jupiter, and 
is -2.9 +/- .3.  Note prediction below of mag 4.7. 
 
Ir P0A 63 mag 5 or 6 
          up to mag 5?                 19980830  93345?? 
          mag 4?       glint           19980830  93349.19 
          down to mag 5?               19980830  93358.20 
          lost mag 7?                  19980830  93432.02 
 
Ir P00 64 mag 6?  B mu Peg to BR Jupiter 
          lost mag 7?                  19980830  94339.10 
 
Ir P01 65 possibly seen briefly B zeta Peg 
 
Ir P02 66 not seen 
 
 
P09 is the designation used in my recent post suggesting a convenient 
nomenclature for visual observation.  Historically, Ir 62. 
 
Flat maxima, PPAS code: M, are quite difficult to judge.  A goodly number 
of timings of glints, and "down to"s, are probably 2 to 4 s late.  The 
timing recorded at 19980830 90442.44 seemed especially late, perhaps 4 or 
5 s. 
 
If you find a time given only to the nearest minute which is not 
consistent to the stated (or unstated) accuracy for a recorded OBS, the 
OBS is real, and the time is simply a rough time which was conveniently 
available.  I try not to veer too far toward OCD (obsessive-compulsive 
disorder); though I do try to make the precise times precise because that 
may be useful.  E.g., 19980828  823? may fall into this category. 
 
 
To change the subject a bit, after I started dialing 1-900-410-TIME to 
cope with the missing WWV on one occasion, it took almost 12 s to be 
connected to the preliminary announcement and an additional 17 seconds 
before I heard the first beep.  I believe I was not charged for these 
29 s. 
 
 
Ir P2S 27 has been rather irregular lately.  There are a couple of bright 
flashes fairly close together, one or both of which don't occur on each 
rev, making it very tricky.  The one below is pretty consistent. 
 
PPAS(beginning): 
Walter I. Nissen, Jr., CDP, dk058@cleveland.freenet.edu, 55 Barrett RD #808, 
Berea, OH 44017-1657, USA, 440-243-4980, -81d 51.823', 41d 22.413', 256m, 7x35 
86- 19BJ 98-08-20  1:32:57.1 WN   34.5  .3  12    2.87 FF', sm, SPOT 1 BJ = 
                                                       17206, mag 5? -> inv 
96- 37 B 98-08-20  1:38:48.1 WN   25.6 1.    4    6.4  AA', TOMS R = 23941, 
                                                       mag 4 or 5 -> mag 6? 
93- 61 A 98-08-20  2:21: 3.7 WN   49.7  .4   4   12.4  FF', Spot 3 = 22823, 
                                          mostly mag 4? Fs, 1 mag 0?, 1 mag 1? 
85- 79 B 98-08-26  1:15:19.5 WN  141.8 1.5   6   23.6  A or M, C* 1680 r = 16012 
97- 51 D 98-08-26  1:54:33.5 WN   38.8  .8  10    3.9  FF', Iridium 27 = 24947 
 
 
Cheers. 
 
Walter Nissen                   dk058@cleveland.freenet.edu 
-81.8637, 41.3735, 256m elevation 
 
--- 
 
Details: 
Latitude:  41.37350  Longitude:  -81.86370  Altitude:  256.0 m 
Time Zone: UTC  +0.0 h 
                      Iridium Coordinates  Range   Sat   Solar                Peak  Std    Maximum Flare 
Ir   Date      Time    Azm El   RA   Decl  (km)  N Ill Azm  Elev M FlrAng Mag  Mag  Mag Latitude Longitude 
62 98- 8-27  9:22:30.0 246 67  0h38  29.1  844.7 D Lit  61 -15.2 L 10.15  4.6 -8.5  4.8  42.7613  -81.0449 
62 98- 8-27  9:22:55.0 224 60  0h52  17.5  888.6 D Lit  61 -15.1 L  4.23  2.5 -8.4  2.7  41.3827  -80.9955 
62 98- 8-27  9:23:30.0 208 49  1h05   3.5 1000.1 D Lit  61 -15.1 L 12.82  5.4 -8.2  5.3  39.4571  -80.9356 
 
63 98- 8-27  9:31:30.0 263 55 23h44  29.4  927.9 D Lit  62 -13.7 L 14.84  5.6 -8.3  5.7  43.2000  -83.3680 
63 98- 8-27  9:32:10.0 236 49  0h12  13.1  991.7 D Lit  62 -13.6 L  6.22  3.6 -8.2  3.6  40.9934  -83.2888 
63 98- 8-27  9:32:50.0 220 40  0h31  -0.6 1124.3 D Lit  63 -13.5 L 13.51  5.7 -8.0  5.4  38.7936  -83.2235 
 
64 98- 8-27  9:41:10.0 249 42 23h34  14.4 1092.7 D Lit  64 -12.1 L 14.69  5.9 -8.0  5.6  41.4297  -85.5718 
64 98- 8-27  9:41:30.0 240 40 23h46   7.8 1140.9 D Lit  64 -12.1 L 13.95  5.8 -8.0  5.5  40.3290  -85.5362 
64 98- 8-27  9:41:40.0 236 38 23h52   4.7 1170.6 D Lit  64 -12.0 L 14.34  5.9 -7.9  5.6  39.7792  -85.5197 
 
33 98- 8-28  2:01:30.0 348 29  9h42  73.8 1417.4 A Lit 304 -19.6 L 13.72  7.0 -6.8  5.5  30.2083  -83.5366 
33 98- 8-28  2:03:37.5 356 12  7h34  60.5 2189.7 A Lit 305 -19.9 L  1.97  3.2 -5.8  0.8  37.4502  -80.9695 
33 98- 8-28  2:06:30.0 000 00  7h02  48.2 3310.7 A Lit 305 -20.3 L  9.41  7.9 -5.0  4.6  48.7366  -76.2867 
 
65 98- 8-28  9:16:30.0 243 67  0h41  28.4  843.3 D Lit  60 -16.4 L 10.32  4.6 -8.5  4.8  42.6747  -80.6296 
65 98- 8-28  9:16:50.0 225 61  0h51  19.0  877.9 D Lit  60 -16.4 L  6.12  3.4 -8.4  3.6  41.5768  -80.5916 
65 98- 8-28  9:17:30.0 207 48  1h06   2.9 1004.2 D Lit  60 -16.2 L 14.18  5.7 -8.1  5.6  39.3865  -80.5256 
 
66 98- 8-28  9:25:30.0 260 56 23h49  28.1  930.2 D Lit  61 -14.9 L 12.46  5.2 -8.3  5.3  43.0175  -82.8976 
66 98- 8-28  9:26:05.0 236 50  0h12  13.9  988.3 D Lit  62 -14.8 L  4.19  2.7 -8.2  2.7  41.1011  -82.8317 
66 98- 8-28  9:26:50.0 218 40  0h33  -1.5 1139.1 D Lit  62 -14.7 L 13.82  5.8 -7.9  5.5  38.6456  -82.7617 
 
67 98- 8-28  9:35:00.0 251 43 23h30  16.3 1073.7 D Lit  63 -13.4 L 13.66  5.7 -8.1  5.5  41.7295  -85.1899 
67 98- 8-28  9:35:20.0 242 41 23h43   9.5 1117.9 D Lit  63 -13.3 L 12.36  5.5 -8.0  5.2  40.6320  -85.1546 
67 98- 8-28  9:35:40.0 234 38 23h54   3.2 1177.4 D Lit  63 -13.3 L 13.40  5.8 -7.9  5.4  39.5364  -85.1226 
 
73 98- 8-30  9:04:20.0 240 68  0h43  28.2  838.8 D Lit  58 -18.8 L 12.61  5.1 -8.5  5.3  42.6542  -79.7666 
73 98- 8-30  9:04:40.0 222 62  0h53  18.8  874.4 D Lit  58 -18.8 L 10.05  4.6 -8.4  4.8  41.5675  -79.7311 
73 98- 8-30  9:05:10.0 208 52  1h04   6.3  964.5 D Lit  58 -18.7 L 14.49  5.6 -8.2  5.6  39.9416  -79.6833 
 
70 98- 8-30  9:13:20.0 260 57 23h47  29.0  915.3 D Lit  60 -17.4 L 11.80  5.0 -8.3  5.1  43.1068  -82.0959 
70 98- 8-30  9:13:52.4 237 52  0h10  15.5  965.0 D Lit  60 -17.3 L  0.73 -1.9 -8.3 -1.9  41.3460  -82.0374 
70 98- 8-30  9:14:40.0 217 41  0h32  -1.2 1121.2 D Lit  60 -17.1 L 13.70  5.8 -8.0  5.5  38.7698  -81.9653 
 
62 98- 8-30  9:22:30.0 263 46 23h13  24.5 1033.1 D Lit  61 -15.9 L 14.95  5.8 -8.1  5.7  42.9684  -84.3583 
62 98- 8-30  9:23:10.0 242 42 23h41  10.4 1101.2 D Lit  62 -15.8 L  8.92  4.7 -8.0  4.5  40.7949  -84.2884 
62 98- 8-30  9:23:50.0 227 35  0h02  -1.9 1231.4 D Lit  62 -15.6 L 13.63  5.9 -7.8  5.5  38.6303  -84.2299 
 
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