FSMY: 2001 Update

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The Forward Scatter Meteor Year: 2001 Update

The following information is copied from WGN 29-3, June 2001, the bimonthly magazine of the International Meteor Organization and is reproduced with the kind permission of the author Alastair McBeath.

Table 1 - 

Forward-scatter radio meteor echo peaks found from 1993 August - 1997 June, as amended by observations from 1997 July - 2000 December.

Column one gives the solar longitude (for equinox J2000.0) an echo-count enhancement was recorded during. Longitudes given in square parentheses, "[]", indicate peaks found only since 1997 July. These parentheses' are similarly employed in columns two and three.

Column two (+ Solar Longitude) shows the spread in degrees of solar longitude sometimes noted by observers before and after the period in column one, but not necessarily in every year. A single number indicates that both the start and end solar longitudes may be so modified in some years (e.g. interval Solar Longitude = 314° to 318°, + 2°; greatest extent of enhancement thus solar Longitude = 312° to 320°), while two numbers indicate different amounts should be allowed for at the start (first number) and end (second number) of the period. Thus the interval 309° to 310° has been found to extend from 307° to 311° at times.

Column three indicates the relative strengths of the solar longitude peaks on a simple three-point scale (weak-medium-strong). This scale has been simplified from the original five point one used in the 1993 - 1997 analysis, and is no longer as numerically based as that earlier scale. Some comments on poorly confirmed peaks or unusual events are noted too.

Column four gives possible associated meteor showers (most minor ones associated by date only), and their peak solar longitudes. The three-letter IMO shower code is used for night-time shower data extracted from [6]; daylight shower information from the same source is indicated by unreferenced shower names consisting of the standard IAU constellation abbreviation, amended by adding the appropriate Bayer letter or month name in full, in brackets where necessary (e.g. the daytime b-Taurids become "b-Tau"; the April Piscids become "Psc (April)"). Other sources include: "Artoos I" and "II" [7]; "HV" [8]; "K" [9]; and "*" [10]. The use of set parentheses here ("{ }") indicates a shower whose radiant has a high southerly declination, which may never rise from some of the radio observing sites employed.

Column five gives relevant notes on each specific echo-count enhancement.

Solar Longitude interval + Solar Longitude Strength Possible Associated showers Notes
281 - 287° none 281° medium; 282° - 283° strong; 284° - 287° weak 283° QUA; 287° r-Geminids ([9] 11-12). Main peak generally at 283°.
289° 1° -0° in 2000 only weak 287° r-Geminids ([9] 11-12); 290 - 291° d-Cancrids ([8] 143). Poorly confirmed in 1999 and 2000.
290° - 294° none weak 290° - 291° d-Cancrids ([8] 143); 292° - 296° d-Cancrids ([9] 5-7). No clear single peak.
295° none weak; clear only in 1997 and 2000 292° - 296° d-Cancrids ([9] 5-7). Hardly noticeable in 1998 - 1999.
298° weak 297° DCA. Only seen since 1997.
300° - 302° weak 300° d-Cancrids ([9] 5-7); 300° a-Hydrids ([9] 12-14);  Canes Venaticids ([9] 19-20). Usually best at 299°, and may blend over 298° - 300°+.
[304° - 305°] [none] [weak] 304° Canes Venaticids ([9] 19-20); 304° - 305° January Coma Berenicids [11]. First found in 1998; weakly recovered in 1999 - 2000; notably in long duration echoes.
309° - 310° 2° -1° weak 309° - 313° Capricornids-Sagittarids ([9] 25-26); 312° - 313° Cap/Sgr. Continued to 311° in 1999 and 2000.
314° - 318° 314° weak; 315° medium; 316° - 318° weak. 309° - 313° Capricornids-Sagittarids ([9] 25-26); 312° - 313° Cap/Sgr; 316° - 321° Aurigids ([9] 23-25); {319° ACE}. Main peak time seems variable, 314° (1999), 313° (2000).
320° - 322° none weak 316° - 321° Aurigids ([9] 23-25); {319° ACE}; 325° c-Cap.  Confirmed 1998 - 2000.
[326°] [1°(?)-0°] [weak] 325° c-Cap.  325° in 1998, but 326° only since.
328° 1°-2° weak 325° c-Cap; 330° - 336° d-Leonids ([8] 148). Confirmed 1998 - 2000.
[331°] [none] [weak] 330° - 336° d-Leonids ([8] 148). Seen since 1998, but poorly found in 1999.
333° - 342° none 333° - 335° weak; 336° - 337° medium; 338° - 342° weak. 330° - 336° d-Leonids ([8] 148); 336° DLE; 340° - 355° Virginids ([8] 155); 319° r-Leonids ([9] 48). Generally confirmed 1998 - 2000.
 344° 0° -1° weak 340° - 355° Virginids ([8] 155). Confirmed 1998 - 2000.
 346° - 347° none weak 340° - 355° Virginids ([8] 155). Typically found on both dates.
 350° none? weak 340° - 355° Virginids ([8] 155). poorly confirmed, ~349° - 352°  (?).
 352° - 355° none weak 340° - 355° Virginids ([8] 155); {353° GNO} Typically best at 352° or 354°.
 357° - 358° 1° -0° weak 340° - 355° Virginids ([8] 155)?; 359° - 0°  θ-Virginids ([9] 44 - 46). Confirmed 1998 - 2000.
 359° - 4° none 359° medium (?); 0° - 3° weak; 4° medium (?). 359° - 0° θ-Virginids ([9] 44 - 46);  0° b-Leonids ([9] 35 - 37). 389° in 1998 - 1999; 4° in 1999 - 2000; 2° was weak-medium in 1999 too.
7° - 8° 1° -3° weak 7° - 9° h-Draconids ([9] 33 - 35). Commonly ill defined
14° - 19° 1° -0° 14° - 16° weak; 17° medium (?); 18° - 19° weak. 17° - 28° a-Virginids ([9] 60 - 64). Commonly ill defined
21° 1° -0° weak 17° - 28° a-Virginids ([9] 60 - 64). 21° since 1999
22° - 24° none weak 17° - 28° a-Virginids ([9] 60 - 64); 24° - 25° g-Virginids ([9] 64 - 65). First found 1997; very weak poorly-confirmed in 1999 - 2000.
25° - 27° 1° -0° weak 17° - 28° a-Virginids ([9] 60 - 64); 24° - 25° g-Virginids ([9] 64 - 65). Sometimes blends with previous peak.
30° - 33° none 32° medium; others weak 30° Psc (April); 32° LYR. Better defined than in original FSMY.
34° - 39° 0° -2° weak {33° - 34° PPU}; 34° d-Psc. Commonly ill defined
40° weak 45° - 46° ETA. May blend with previous peaks.
42° - 50° none 42° - 45° weak; 46° strong; 47° - 50° medium. 45° - 46° ETA; 49° e-Ari. Variable peak strengths and timings.
52° - 53° none 52° weak; 53° medium. 45° - 46° ETA; 55° - 56° Ari (May) Confirmed 1998 - 2000.
54° - 58° none weak 55° - 56° Ari (May); 59° o-Cet. Generally confirmed 1998 - 2000.
[60° - 61°] [none] [weak] 59° o-Cet. First found 1998.
62° - 66° none weak 66° - 70° Sagattarids ([8] 168). Poorly confirmed 1998 - 2000.
69° weak 66° - 70° Sagattarids ([8] 168). Revised activity using 1998 - 2000 data.
71° none weak - medium? 66° - 70° Sagattarids ([8] 168). Stronger activity not confirmed 1998 - 2000.
73° none weak 66° - 70° Sagattarids ([8] 168). Confirmed 1998 - 1999.
75° - 82° 2° -0° 75° medium; 76° weak; 77° medium; 78° weak; 79° medium; 80° -  82° weak 77° Ari; 79° z-Per. Stronger peaks a 75° - 76°,  78° -  79° and 81° - 82° / 83°.
84° 1° -2° weak 85° June Lyrids ([9] 99 - 103);  90° Sagittarids ([8] 168). Confirmed 1998 - 2000. May blend with previous peaks.
89° - 97° none 89° - 90° weak; 91° - 93° medium;  94° - 97° weak.  90° Sagattarids ([8] 168); 96° JBO; 97° b-Tau. Strong June Boötid peak at 95° - 96° in 1998 only. Other peak timings variable.
99° weak 97° b-Tau. Generally confirmed 1997 - 2000.
107° 4°(?) -21° weak 107° - 108° JPE. Typically poorly confirmed 1997 - 2000.
111° - 114° none weak {111° PHE} Possible peak at 112°?
[115°] [none] [weak] Aquarid- Capricornid complex (late July)? 1998 only; poorly confirmed since.
116° none weak Aquarid- Capricornid complex (late July)? Only found in 1996 and 1999 (long duration echoes).
120° 1° -3° weak Aquarid- Capricornid complex (late July). Confirmed 1997 - 2000.
122° - 128° 2° -3° 122° - 123° weak; 124° - 125° medium to strong;  126° - 128° weak.  125° PAU; 125° SDA (124° - 126° [8] 179);   127° CAP (124° - 130° [8] 183); Aquarid - Capricornid complex (early August).  Sometimes blended with previous peak. Peak at 128° now considered linked. Highest counts usually 124° - 126°.
129° 0° -1° weak Aquarid - Capricornid complex (early August);  132° SIA (133° - 137° [8] 187). Previously set at 130°, but not well confirmed there.
[131° - 133°] [none] [weak] Aquarid - Capricornid complex (early August);  132° SIA (133° - 137° [8] 187). First found 1999. clearest in long duration echoes at 131°,1999 - 2000.
135° none weak 132° SIA (133° - 137° [8] 187); 136° NDA (133° - 139° [8] 198). very poorly confirmed 1997 - 2000.
137° - 142° 4° -0° 137° medium; 138° weak; 139° - 140° medium - strong; 141° - 142° weak.  136° NDA (133° - 139° [8] 198); 139° - 140° PER. Well confirmed main peak between 139° - 141°.
144° 1° -2° weak 136° KCG; 147° NIA (146° - 153° [8] 187). Generally confirmed 1997 - 2000.
[148° - 149°] [none] [weak] 147° NIA (146° - 153° [8] 187). First found 1998 ill-confirmed since.
155° 5° -1° weak 147° NIA (146° - 153° [8] 187); 152° g-Leo. Confirmed 1997 - 2000, but no clear peak.
[158° - 159°] [none] [weak] 159° AUR. First found 1998. Generally confirmed since.
160° - 163° none 160° - 161° weak. 162° - 163° medium.  159° AUR. Generally confirmed 1997 - 2000.
165° none weak.  166° DAU. Confirmed present 1997, 1999, and 2000.
169° 3° -0° weak.  169° h-Draconids ([9] 180 - 181) Confirmed 1997 -  2000.
170° 0° -1° weak.  169° h-Draconids ([9] 180 - 181) First found 1996; confirmed 1997 - 1999.
172° - 173° 0° -1° weak. 174° ([7] Artoos I) Confirmed 1997 - 1999.
[174°] [none] [weak] 174° ([7] Artoos I) Found in 1999, possibly extending to 175° for European observers only; stronger in southern hemisphere results in 2000.
176° - 177° 0° -2° 176° medium; 177° weak. 177° SPI Confirmed 1997 - 2000.
180° - 181° none weak (1996, one dataset showed weak activity from 178° to 182°). 179° k-Aquarids*; 181° g-Piscids ([9] 181 - 182); 181° October Cetids ([9] 208 - 209). Sometimes from 179°, but confirmed 1997 - 2000.
183° 1° -0° strong 182° October Cetids ([9] 208 - 209); 183° - 187° ([7] Artoos II); 184° Sex; 185° - 190° Sextantids ([9] 205 - 207). Well confirmed in 1998 - 1999, less well detected in 1997 and 2000.
185° - 187° none usually weak, but strong at 186° in 1999.  183° - 187° ([7] Artoos II); 184° Sex; 185° - 190° Sextantids ([9] 205 - 207). Found 1996; confirmed 1997 - 2000.
190° - 192° 1° -3° 190° weak; 191° medium; 192° weak. 185° - 190° Sextantids ([9] 205 - 207); 190° Capricornids (October)*; 192° October Cetids  ([9] 208 - 209) ; 192° s-Orionids*. Confirmed 1997 - 2000. Up to three peaks between 189° - 195° in some years.
195° 0° -1° weak to strong (1998 only) 194° October Arietids ([9] 183 -185); 195° - 196° GIA. Most likely due to Draconids, but 190° - 192° peak often extends to 195° as in 1999 - 2000.
198° - 199° 0° -1° weak - Confirmed 1997 - 1999; poorly found in 2000.
201° - 212° none 201° weak; 202° medium; 203° - 206° weak; 207° - 209° strong; 209° - 212° weak. 203°, 214° October Cetids ([9] 208 -209); 205° EGE; 208° ORI (205° - 212° [8] 222). Confirmed 1997 - 2000. Strongest peak usually at 208°.
[216° - 217°] [none] [weak] Taurid "swarm" [4, 5]. Only found in 1998, coincident with higher visual Taurid rates. Very weak, less clear peaks found in 1999 - 2000.
219° 1°(?) weak Taurid fireballs? Weak confirmation 1997 - 1998, better confirmed 1999 - 2000.
224° 2° -3° weak 223° STA (220° - 230°, especially 224° - 225° [8] 232). Confirmed 1998 - 2000 particularly.
227° 1° -4° weak 230° NTA (220° - 230°, especially 227° - 230° [8] 232). Generally confirmed 1997 - 2000, especially around 227° - 228°. May blend into 230°.
230° 0° -1° weak 230° NTA (220° - 230°, especially 227° - 230° [8] 232). Formerly found at 229°, but noted at  230° - 231° since 1997.
233° - 237° none 233° medium; 234° - 236° medium to strong; 237° weak. 235° LEO. Confirmation of visual high activity since 1998. Main peak times variable.
238° - 239° none weak, except 1995 239° AMO. Confirmed weak activity 1997 - 2000.
240° - 248° none weak 250° XOR (248° - 250° [8] 248). Several peaks, but timings inconsistent.
249° - 250° none weak 250° XOR (248° - 250° [8] 248). Confirmed 1997 - 2000.
[252°] [1° -0°] [weak] - First found 1998, confirmed each year since.
254° 0° -3° weak {254° PHO}; 257° MON. Generally confirmed 1997 - 2000.
257° 1° -0° weak 257° MON. Formery at 256°.
258° - 264° 1° -0° 258° weak; 259° - 260° medium; 261° - 263° medium to strong; 264° weak. 257° MON; 260° HYD  (254° - 256° [8] 260); .262° GEM Generally confirmed 1997 - 2000, but parameters amended from observations of slightly later peak than original FSMY.
265° - 267° none weak 265°(?) s-Hydrids ([8] 260); 268°  COM (265° - 267° [8] 271) Confirmed 1997 - 2000; peak generally 265° - 266°.
269° - 270° 0° -1° weak to medium 268°  COM (265° - 267° [8] 271); 271°  URS (269° - 271° [8] 274).  Confirmed 1997 - 2000.
272° - 275° 0° -1° weak 268°  COM (265° - 267° [8] 271); 271°  URS (269° - 271° [8] 274).  Possible peak at 273° in 1997 and 1999.
278° - 279° none weak 268°  COM (265° - 267° [8] 271).  Usually at 278° mainly.

References

[1] A. McBeath, "The Forward Scatter Meteor Year" in: Proceedings IMC 1997, Petnica, Yugoslavia, A. Knöfel, A. McBeath (eds.), IMO, 1998, pp. 39 - 54.

[2] A. McBeath, "SPA Meteor Section Preliminary radio Results: 1996 Leonids", WGN 25:1 (February 1997), 99. 45 - 53.

[3] A. McBeath, "More on the Forward Scatter Meteor Year", in: Proceedings IMC 1998, Stará Lesná, Slovakia, R. Arlt, A. Knöfel (eds.), IMO, 1999, pp. 102 - 109.

[4] A. McBeath, "SPA Meteor Section Results: September - October 1998", WGN 27:3/4 (June - August 1999), pp. 209 - 214.

[5] R. Arlt, Glancing at the Taurids of the Last Decade", in: IMC Proceedings 1999, Frasso Sabino, Italy, R. Arlt (ed.), IMO, 2000, pp. 112 - 120.

[6] A. McBeath, R. Arlt (comp.) "2001 Meteor Shower Calendar", IMO 2000 (English), (French), (Spanish).

[7] D. Artoos, "Possible Radio Activity in September 1990", WGN 18:4 (August 1990), pp. 101 - 102.

[8] J. Rendtel, R. Arlt, A. McBeath (eds.), "Handbook for Visual Meteor Observers", IMO, 1995.

[9] G. W. Kronk, "Meteor Showers: A Descriptive Catalog", Enslow Publishers, 1988.

[10] A. McBeath (comp.), "1995 Meteor Shower Calendar", IMO, 1994.

[11] A. McBeath, R. Gorelli, "Call for Observations: January 24, 2001", WGN 28:6 (December 2000), pp. 190 - 191.

[12] K. Maegawa, "HRO A New Forward-Scatter Observation Method Using a Ham-Band Beacon", WGN 27:1 (February 1999), pp 64 - 72.