how many different flyby's have been done for the halley comet?
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col : comet | discoverer(s) or namesake(s) | orbital period (years) | spacecraft encounter(s) row 1 : 1p/halley | halley | 75.32 | giotto (flyby 1986), vega 1 ( row 2 : 2p/encke | encke | 3.30 |  row 3 : 3d/biela | biela |  |  row 4 : 4p/faye | faye | 7.51 |  row 5 : 7p/pons–winnecke | pons & winnecke | 6.36 |  row 6 : 10p/tempel (tempel 2) | tempel | 5.37 |  row 7 : 12p/pons–brooks | pons & brooks | 70.85 |  row 8 : 16p/brooks (brooks 2) | brooks | 6.14 |  row 9 : 18d/perrine–mrkos | perrine & mrkos |  |  row 10 : 19p/borrelly | borrelly | 6.85 | deep space 1 (flyby 2001) row 11 : 22p/kopff | kopff | 6.43 | craf (rendezvous/lander 2000 – cancelled) row 12 : 25d/neujmin (neujmin 2) | neujmin |  |  row 13 : 29p/schwassmann–wachmann (schwa | schwassmann & wachmann | 14.69 |  row 14 : 33p/daniel | daniel | 8.07 |  row 15 : 34d/gale | gale |  |  row 16 : 36p/whipple | whipple | 8.55 |  row 17 : 37p/forbes | forbes | 6.35 |  row 18 : 43p/wolf–harrington | wolf & harrington | 6.13 |  row 19 : 46p/wirtanen | wirtanen | 5.44 | ice (distant flyby 2018 – proposed), cho row 20 : 47p/ashbrook–jackson | ashbrook & jackson | 8.35 |  row 21 : 50p/arend | arend | 8.25 |  row 22 : 51p/harrington | harrington | 7.13 |  row 23 : 53p/van biesbroeck | van biesbroeck | 12.6 |  row 24 : 54p/de vico–swift–neat | de vico & swift & neat | 7.38 |  row 25 : 55p/tempel–tuttle | tempel & tuttle | 33.24 |  row 26 : 56p/slaughter–burnham | slaughter & burnham | 11.54 |  row 27 : 57p/du toit–neujmin–delport | du toit & neujmin & delporte | 6.40 |  row 28 : 59p/kearns–kwee | kearns & kwee | 9.51 |  row 29 : 62p/tsuchinshan (tsuchinshan | tsuchinshan | 6.63 |  row 30 : 66p/du toit | du toit | 14.71 |  row 31 : 68p/klemola | klemola | 10.83 |  row 32 : 69p/taylor | taylor | 7.65 |  row 33 : 70p/kojima | kojima | 7.06 |  row 34 : 71p/clark | clark | 5.53 |  row 35 : 72d/denning–fujikawa | denning & fujikawa |  |  row 36 : 76p/west–kohoutek–ikemura | west & kohoutek & ikemura | 6.48 |  row 37 : 77p/longmore | longmore | 6.88 |  row 38 : 79p/du toit–hartley | du toit & hartley | 5.28 |  row 39 : 80p/peters–hartley | peters & hartley | 8.12 |  row 40 : 81p/wild (wild 2) | wild | 6.41 | stardust (flyby/sample return 2004)
how many different flyby's have been done for the halley comet?
Comet Discoverer(s) or namesake(s) Orbital period (years) Spacecraft encounter(s)
1P/Halley Halley 75.32 Giotto (flyby 1986), Vega 1 (flyby 1986), Vega 2 (flyby 1986), Suisei (flyby 1986) ICE (distant flyby 1986), Sakigake (distant flyby 1986)
2P/Encke Encke 3.30
3D/Biela Biela
4P/Faye Faye 7.51
5D/Brorsen Brorsen
6P/d'Arrest d'Arrest 6.54
7P/Pons–Winnecke Pons & Winnecke 6.36
8P/Tuttle Tuttle 13.61
9P/Tempel (Tempel 1) Tempel 5.58 Deep Impact (impactor/flyby 2005), Stardust (flyby 2011)
10P/Tempel (Tempel 2) Tempel 5.37
11P/Tempel–Swift–LINEAR Tempel & Swift & LINEAR 6.37
12P/Pons–Brooks Pons & Brooks 70.85
13P/Olbers Olbers 69.52
14P/Wolf Wolf 8.74
15P/Finlay Finlay 6.50
16P/Brooks (Brooks 2) Brooks 6.14
17P/Holmes Holmes 6.88
18D/Perrine–Mrkos Perrine & Mrkos
19P/Borrelly Borrelly 6.85 Deep Space 1 (flyby 2001)
20D/Westphal Westphal
21P/Giacobini–Zinner Giacobini & Zinner 6.60 ICE (distant flyby 1985)
22P/Kopff Kopff 6.43 CRAF (rendezvous/lander 2000 – cancelled)
23P/Brorsen–Metcalf Brorsen & Metcalf 70.52
24P/Schaumasse Schaumasse 8.25
25D/Neujmin (Neujmin 2) Neujmin
26P/Grigg–Skjellerup Grigg & Skjellerup 5.31 Giotto (flyby 1992)
27P/Crommelin Crommelin 27.93
28P/Neujmin (Neujmin 1) Neujmin 18.17
29P/Schwassmann–Wachmann (Schwassmann–Wachmann 1) Schwassmann & Wachmann 14.69
30P/Reinmuth (Reinmuth 1) Reinmuth 7.34
31P/Schwassmann–Wachmann (Schwassmann–Wachmann 2) Schwassmann & Wachmann 8.75
32P/Comas Solá Comas Solá 8.80
33P/Daniel Daniel 8.07
34D/Gale Gale
35P/Herschel–Rigollet Herschel & Rigollet 155
36P/Whipple Whipple 8.55
37P/Forbes Forbes 6.35
38P/Stephan–Oterma Stephan & Oterma 37.72
39P/Oterma Oterma 19.53
40P/Väisälä (Väisälä 1) Väisälä 10.82
41P/Tuttle–Giacobini–Kresák Tuttle & Giacobini & Kresák 5.42
42P/Neujmin (Neujmin 3) Neujmin 10.70
43P/Wolf–Harrington Wolf & Harrington 6.13
44P/Reinmuth (Reinmuth 2) Reinmuth 7.08
45P/Honda–Mrkos–Pajdušáková Honda & Mrkos & Pajdušáková 5.26
46P/Wirtanen Wirtanen 5.44 ICE (distant flyby 2018 – proposed), CHopper (lander 2022—proposed)
47P/Ashbrook–Jackson Ashbrook & Jackson 8.35
48P/Johnson Johnson 6.95
49P/Arend–Rigaux Arend & Rigaux 6.73
50P/Arend Arend 8.25
51P/Harrington Harrington 7.13
52P/Harrington–Abell Harrington & Abell 7.54
53P/Van Biesbroeck Van Biesbroeck 12.6
54P/de Vico–Swift–NEAT de Vico & Swift & NEAT 7.38
55P/Tempel–Tuttle Tempel & Tuttle 33.24
56P/Slaughter–Burnham Slaughter & Burnham 11.54
57P/du Toit–Neujmin–Delporte du Toit & Neujmin & Delporte 6.40
58P/Jackson–Neujmin Jackson & Neujmin 8.24
59P/Kearns–Kwee Kearns & Kwee 9.51
60P/Tsuchinshan (Tsuchinshan 2) Tsuchinshan 6.56
61P/Shajn–Schaldach Shajn & Schaldach 7.06
62P/Tsuchinshan (Tsuchinshan 1) Tsuchinshan 6.63
63P/Wild (Wild 1) Wild 13.25
64P/Swift–Gehrels Swift & Gehrels 9.35
65P/Gunn Gunn 6.88
66P/du Toit du Toit 14.71
67P/Churyumov–Gerasimenko Churyumov & Gerasimenko 6.45 Rosetta (orbiter 2014)
68P/Klemola Klemola 10.83
69P/Taylor Taylor 7.65
70P/Kojima Kojima 7.06
71P/Clark Clark 5.53
72D/Denning–Fujikawa Denning & Fujikawa
73P/Schwassmann–Wachmann (Schwassmann–Wachmann 3) Schwassmann & Wachmann 5.36
74P/Smirnova–Chernykh Smirnova & Chernykh 8.51
75D/Kohoutek Kohoutek ~7
76P/West–Kohoutek–Ikemura West & Kohoutek & Ikemura 6.48
77P/Longmore Longmore 6.88
78P/Gehrels (Gehrels 2) Gehrels 7.22
79P/du Toit–Hartley du Toit & Hartley 5.28
80P/Peters–Hartley Peters & Hartley 8.12
81P/Wild (Wild 2) Wild 6.41 Stardust (flyby/sample return 2004)
82P/Gehrels (Gehrels 3) Gehrels 8.43
83D/Russell (Russell 1) Russell
84P/Giclas Giclas 6.97
85P/Boethin Boethin 11.81
86P/Wild (Wild 3) Wild 6.91
87P/Bus Bus 6.51
88P/Howell Howell 5.49
89P/Russell (Russell 2) Russell 7.26
90P/Gehrels (Gehrels 1) Gehrels 14.85
91P/Russell (Russell 3) Russell 7.67
92P/Sanguin Sanguin 12.43
93P/Lovas (Lovas 1) Lovas 9.20
94P/Russell (Russell 4) Russell 6.58
95P/Chiron = minor planet 2060 Chiron Kowal 50.50
96P/Machholz (Machholz 1) Machholz 5.28
97P/Metcalf–Brewington Metcalf & Brewington 10.51
98P/Takamizawa Takamizawa 7.40
99P/Kowal (Kowal 1) Kowal 15.25
100P/Hartley (Hartley 1) Hartley 6.35
101P/Chernykh Chernykh 13.94
102P/Shoemaker (Shoemaker 1) C. Shoemaker & E. Shoemaker 7.22
103P/Hartley (Hartley 2) Hartley 6.47 Deep Impact (flyby 2010)
104P/Kowal (Kowal 2) Kowal 5.89
105P/Singer Brewster Singer-Brewster 6.47
106P/Schuster Schuster 7.31
107P/Wilson–Harrington = minor planet 4015 Wilson–Harrington Helin & Wilson & Harrington 4.29
108P/Ciffréo Ciffréo 7.26
109P/Swift–Tuttle Swift & Tuttle 133.28
110P/Hartley (Hartley 3) Hartley 6.88
111P/Helin–Roman–Crockett Helin & Roman & Crockett 8.14
112P/Urata–Niijima Urata & Niijima 6.67
113P/Spitaler Spitaler 7.09
114P/Wiseman–Skiff Wiseman & Skiff 6.67
115P/Maury Maury 8.76
116P/Wild (Wild 4) Wild 6.51
117P/Helin–Roman–Alu (Helin–Roman–Alu 1) Helin & Roman & Alu 8.24
118P/Shoemaker–Levy (Shoemaker–Levy 4) C. Shoemaker, E. Shoemaker & Levy 6.44
119P/Parker–Hartley Parker & Hartley 8.89
120P/Mueller (Mueller 1) Mueller 8.43
121P/Shoemaker–Holt (Shoemaker–Holt 2) C.Shoemaker, E.Shoemaker & Holt 8.02
122P/de Vico de Vico 74.35
123P/West–Hartley West & Hartley 7.59
124P/Mrkos Mrkos 5.75
125P/Spacewatch Spacewatch 5.53
126P/IRAS IRAS 13.41
127P/Holt–Olmstead Holt & Olmstead 6.41
128P/Shoemaker–Holt (Shoemaker–Holt 1) C. Shoemaker, E. Shoemaker & Holt 9.59
129P/Shoemaker–Levy (Shoemaker–Levy 3) C. Shoemaker, E. Shoemaker & Levy 8.89
130P/McNaught–Hughes McNaught & Hughes 6.66
131P/Mueller (Mueller 2) Mueller 7.08
132P/Helin–Roman–Alu (Helin–Roman–Alu 2) Helin & Roman & Alu 8.28
133P/Elst–Pizarro = minor planet 7968 Elst–Pizarro Elst & Pizarro 5.62
134P/Kowal–Vávrová Kowal & Vávrová 15.6
135P/Shoemaker–Levy (Shoemaker–Levy 8) C. Shoemaker, E. Shoemaker & Levy 7.50
136P/Mueller (Mueller 3) Mueller 8.62
137P/Shoemaker–Levy (Shoemaker–Levy 2) C. Shoemaker, E. Shoemaker & Levy 9.55
138P/Shoemaker–Levy (Shoemaker–Levy 7) C. Shoemaker, E. Shoemaker & Levy 6.91
139P/Väisälä–Oterma Väisälä & Oterma 9.61
140P/Bowell–Skiff Bowell & Skiff 16.18
141P/Machholz (Machholz 2) Machholz 5.23
142P/Ge–Wang Ge & Wang 11.09
143P/Kowal–Mrkos Kowal & Mrkos 8.93
144P/Kushida Kushida 7.57
145P/Shoemaker–Levy (Shoemaker–Levy 5) C. Shoemaker, E. Shoemaker & Levy 8.66
146P/Shoemaker–LINEAR C. Shoemaker, E. Shoemaker & LINEAR 8.12
147P/Kushida–Muramatsu Kushida & Muramatsu 7.41
148P/Anderson–LINEAR Anderson & LINEAR 7.07
149P/Mueller (Mueller 4) Mueller 9.02
150P/LONEOS LONEOS 7.66
151P/Helin Helin 14.10
152P/Helin–Lawrence Helin & Lawrence 9.54
153P/Ikeya–Zhang Ikeya & Zhang 366.5
154P/Brewington Brewington 10.66
155P/Shoemaker (Shoemaker 3) C. Shoemaker & E. Shoemaker 17.09
156P/Russell–LINEAR Russell & LINEAR 6.84
157P/Tritton Tritton 6.29
158P/Kowal–LINEAR Kowal & LINEAR 10.26
159P/LONEOS LONEOS 14.32
160P/LINEAR LINEAR 7.95
161P/Hartley–IRAS Hartley & IRAS 21.43
162P/Siding Spring Siding Spring 5.32
163P/NEAT NEAT 7.30
164P/Christensen Christensen 6.97
165P/LINEAR LINEAR 76.7
166P/NEAT NEAT 51.73
167P/CINEOS CINEOS 64.85
168P/Hergenrother Hergenrother 6.89
169P/NEAT NEAT 4.20
170P/Christensen Christensen 8.63
171P/Spahr Spahr 6.70
172P/Yeung Yeung 6.59
173P/Mueller (Mueller 5) Mueller 13.63
174P/Echeclus = minor planet 60558 Echeclus Spacewatch 35.02
175P/Hergenrother Hergenrother 6.34
176P/LINEAR = minor planet 118401 LINEAR LINEAR 5.71
177P/Barnard (Barnard 2) Barnard 119.67
178P/Hug–Bell Hug & Bell 7.06
179P/Jedicke Jedicke 14.31
180P/NEAT NEAT 7.54
181P/Shoemaker–Levy (Shoemaker–Levy 6) C. Shoemaker, E. Shoemaker & Levy 7.53
182P/LONEOS LONEOS 5.02
183P/Korlevic–Juric Korlevic & Juric 9.58
184P/Lovas (Lovas 2) Lovas 6.62
185P/Petriew Petriew 5.47
186P/Garradd Garradd 10.62
187P/LINEAR LINEAR 9.40
188P/LINEAR–Mueller LINEAR & Mueller 9.13
189P/NEAT NEAT 4.99
190P/Mueller Mueller 8.74
191P/McNaught McNaught 6.64
192P/Shoemaker–Levy (Shoemaker–Levy 1) C. Shoemaker, E. Shoemaker & Levy 17.29
193P/LINEAR–NEAT LINEAR & NEAT 6.56
194P/LINEAR LINEAR [1] 8.00
195P/Hill Hill 16.49
196P/Tichý Tichý IAUC 8917 7.36
197P/LINEAR LINEAR IAUC 8924 4.85
198P/ODAS OCA-DLR Asteroid Survey (ODAS)[2], IAUC 8929 6.78
199P/Shoemaker (Shoemaker 4) C. Shoemaker & E. Shoemaker CBET 1347 14.53
200P/Larsen Larsen 10.92
201P/LONEOS LONEOS [3] 6.47
202P/Scotti Scotti [4] 7.32
203P/Korlevic Korlevic IAUC 8974 10.01
204P/LINEAR–NEAT LINEAR & NEAT IAUC 8974 7.00
205P/Giacobini Giacobini (previously thought lost and designated D/1896 R2) IAUC 8975 6.66
206P/Barnard–Boattini Barnard & Boattini [previously thought lost and designated D/1892 T1 (Barnard 3)] IAUC 8995 5.81
207P/NEAT NEAT IAUC 8996 7.63
208P/McMillan McMillan IAUC 8997, IAUC 9000 8.16
209P/LINEAR LINEAR IAUC 9002 5.04
210P/Christensen Christensen IAUC 9005 5.71
211P/Hill Hill (Catalina Sky Survey) IAUC 9001 6.71
212P/NEAT NEAT IAUC 9010 7.78
213P/Van Ness Van Ness IAUC 9017 6.34
214P/LINEAR LINEAR IAUC 9017 6.84
215P/NEAT NEAT IAUC 9018 8.07
216P/LINEAR LINEAR IAUC 9021 7.63
217P/LINEAR LINEAR 7.83
218P/LINEAR LINEAR 6.11
219P/LINEAR LINEAR 6.98
220P/McNaught McNaught 5.50
221P/LINEAR LINEAR 6.50
222P/LINEAR LINEAR 4.83
223P/Skiff Skiff 8.42
224P/LINEAR–NEAT LINEAR & NEAT 6.30
225P/LINEAR LINEAR 6.99
226P/Pigott–LINEAR–Kowalski Pigott & LINEAR & Kowalski 7.32
227P/Catalina–LINEAR Catalina Sky Survey & LINEAR 6.79
228P/LINEAR LINEAR 8.49
229P/Gibbs Gibbs (Catalina Sky Survey) 7.78
230P/LINEAR LINEAR 6.27
231P/LINEAR–NEAT LINEAR & NEAT 8.08
232P/Hill Hill (Catalina Sky Survey) 9.49
233P/La Sagra La Sagra Sky Survey 5.29
234P/LINEAR LINEAR 7.47
235P/LINEAR LINEAR 8.00
236P/LINEAR LINEAR 7.20
237P/LINEAR LINEAR 6.57
238P/Read Read (Spacewatch) 5.63
239P/LINEAR LINEAR 9.43
240P/NEAT NEAT 7.60
241P/LINEAR LINEAR 10.79
242P/Spahr Spahr 13.20
243P/NEAT NEAT 7.52
244P/Scotti Scotti 10.8
245P/WISE WISE 8.03
246P/NEAT NEAT 8.06
247P/LINEAR LINEAR 7.98
248P/Gibbs Gibbs (Catalina Sky Survey) 14.63
249P/LINEAR LINEAR 4.63
250P/Larson Larson (Catalina Sky Survey) 7.20
251P/LINEAR LINEAR 6.52
252P/LINEAR LINEAR 5.32
253P/PANSTARRS Pan-STARRS 6.47
254P/McNaught McNaught 10.09
255P/Levy Levy 5.29
256P/LINEAR LINEAR 9.96
257P/Catalina Catalina Sky Survey 7.27
258P/PANSTARRS Pan-STARRS 9.22
259P/Garradd Garradd 4.50
260P/McNaught McNaught 7.07
261P/Larson Larson (Mount Lemmon Survey) 6.80
262P/McNaught–Russell McNaught & Russell 18.3
263P/Gibbs Gibbs (Catalina Sky Survey) 5.36
264P/Larsen Larsen 7.68
265P/LINEAR LINEAR 8.77
266P/Christensen Christensen 6.63
267P/LONEOS LONEOS 5.96
268P/Bernardi Bernardi 9.76
269P/Jedicke V. Jedicke & R. Jedicke 19.55
270P/Gehrels Gehrels 17.82
271P/van Houten–Lemmon C. van Houten & I. van Houten-Groeneveld & Mount Lemmon Survey 18.42
272P/NEAT NEAT 9.36
273P/Pons–Gambart Pons & Gambart 188
274P/Tombaugh–Tenagra Tombaugh & Tenagra II Observatory 9.12
275P/Hermann Hermann 13.79
276P/Vorobjov Vorobjov 12.5
277P/LINEAR LINEAR 7.59
278P/McNaught McNaught 7.12
279P/La Sagra La Sagra Sky Survey 6.78
280P/Larsen Larsen 9.63
281P/MOSS Morocco Oukaimeden Sky Survey (MOSS) 10.69
282P 8.76
283P/Spacewatch Spacewatch 8.40
284P/McNaught McNaught 7.04
285P/LINEAR LINEAR 9.52
286P/Christensen Christensen 8.37
287P/Christensen Christensen 8.54
288P/Spacewatch = minor planet (300163) 2006 VW139 Spacewatch 5.32
289P/Blanpain Blanpain 5.33
290P/Jäger Jäger 15.2
291P/NEAT NEAT 9.71
292P/Li Li 15.1
293P/Spacewatch Spacewatch 6.94
294P/LINEAR LINEAR 5.74
295P/LINEAR LINEAR 12.3
296P/Garradd Garradd 6.55
297P/Beshore Beshore (Mount Lemmon Survey) 6.39
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