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<title>Comet Swift–Tuttle</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Comet Swift–Tuttle</span></span>

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</style><div role="note" class="hatnote navigation-not-searchable">For other comets discovered by Lewis A. Swift, see <a href="Comet_Swift" title="Comet Swift">Comet Swift</a>.</div>

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</style><table class="infobox"><caption class="infobox-title">109P/Swift–Tuttle</caption><tbody><tr><td colspan="2" class="infobox-image"><div class="infobox-caption" style="line-height:1.2em;">Sketch of the comet on 23 August 1862 by G. J. Chambers</div></td></tr><tr><th colspan="2" class="infobox-header" style="background-color:#FFE0C2">Discovery</th></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="List_of_minor_planet_discoverers" title="List of minor planet discoverers">Discovered by</a></th><td class="infobox-data"><a href="Lewis_Swift" class="mw-redirect" title="Lewis Swift">Lewis Swift</a><br><a href="Horace_Parnell_Tuttle" title="Horace Parnell Tuttle">Horace Parnell Tuttle</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;">Discovery date</th><td class="infobox-data">16–19 July 1862</td></tr><tr><th colspan="2" class="infobox-header" style="background-color:#FFE0C2">Designations</th></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Minor-planet_designation" title="Minor-planet designation">MPC designation</a></div></th><td class="infobox-data">P/1737 N1; P/1862 O1<br>P/1992 S2</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Provisional_designation_in_astronomy" title="Provisional designation in astronomy">Alternative designations</a></div></th><td class="infobox-data">1737 II; 1862 III;<br>1992 XXVIII</td></tr><tr><th colspan="2" class="infobox-header" style="background-color:#FFE0C2"><a href="Osculating_orbit" title="Osculating orbit">Orbital characteristics</a><sup id="cite_ref-MPC_2-0" class="reference"><a href="#cite_note-MPC-2"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-NK723_3-0" class="reference"><a href="#cite_note-NK723-3"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Yau_1994_4-0" class="reference"><a href="#cite_note-Yau_1994-4"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup></th></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Epoch_(astronomy)" title="Epoch (astronomy)">Epoch</a></th><td class="infobox-data">4 December 1995 (<a href="Julian_day" title="Julian day">JD</a> 2448960.5)</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Observation_arc" title="Observation arc">Observation arc</a></th><td class="infobox-data">2,064 years</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;">Earliest <a href="Precovery" title="Precovery">precovery</a> date</th><td class="infobox-data">69 BC</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;">Number of<br>observations</th><td class="infobox-data">652</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Apsis" title="Apsis">Aphelion</a></th><td class="infobox-data">51.225 AU</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Apsis" title="Apsis">Perihelion</a></th><td class="infobox-data">0.9595 AU</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Semi-major_axis" class="mw-redirect" title="Semi-major axis">Semi-major axis</a></th><td class="infobox-data">26.092 AU</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Orbital_eccentricity" title="Orbital eccentricity">Eccentricity</a></th><td class="infobox-data">0.9632</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Orbital_period" title="Orbital period">Orbital period</a></th><td class="infobox-data">133.28 years</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;">Max. <a href="Orbital_speed" title="Orbital speed">orbital speed</a></th><td class="infobox-data">42.6 km/s (26.5 mi/s)<sup id="cite_ref-speed_1-0" class="reference"><a href="#cite_note-speed-1"><span class="cite-bracket">[</span>a<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;">Min. <a href="Orbital_speed" title="Orbital speed">orbital speed</a></th><td class="infobox-data">0.8 km/s (0.50 mi/s) (2059-Dec-12)</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Orbital_inclination" title="Orbital inclination">Inclination</a></th><td class="infobox-data">113.45°</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Longitude_of_the_ascending_node" title="Longitude of the ascending node">Longitude of<br>ascending node</a></div></th><td class="infobox-data">139.44°</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Argument_of_periapsis" title="Argument of periapsis">Argument of<br>periapsis</a></th><td class="infobox-data">153.00°</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;">Last perihelion</th><td class="infobox-data">12 December 1992</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;">Next perihelion</th><td class="infobox-data">12 July 2126</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Tisserand's_parameter" title="Tisserand's parameter">T<sub>Jupiter</sub></a></th><td class="infobox-data">–0.280</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;">Earth <a href="Minimum_orbit_intersection_distance" title="Minimum orbit intersection distance">MOID</a></th><td class="infobox-data">0.001 AU</td></tr><tr><th colspan="2" class="infobox-header" style="background-color:#FFE0C2"> Physical characteristics<sup id="cite_ref-McDavid_1995_5-0" class="reference"><a href="#cite_note-McDavid_1995-5"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Lamy_2004_6-0" class="reference"><a href="#cite_note-Lamy_2004-6"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></th></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Mean diameter</div></th><td class="infobox-data">26 km (16 mi)</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Synodic_rotation_period" class="mw-redirect" title="Synodic rotation period">Synodic rotation period</a></div></th><td class="infobox-data"><span class="nowrap">67.3<span style="margin-left:0.225em;margin-right:0.225em;">±</span>2.6</span> hours</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;"><a href="Absolute_magnitude#Cometary_magnitudes" title="Absolute magnitude">Comet total<br>magnitude</a> (M1)</th><td class="infobox-data">4.5</td></tr><tr><th scope="row" class="infobox-label" style="white-space:nowrap;line-height:1.2em;">Comet nuclear<br>magnitude (M2)</th><td class="infobox-data">8.5</td></tr></tbody></table>

<td colspan="8" style="text-align:center;"><b>Orbital period<br>at different passages</b><sup id="cite_ref-Yau_1994_4-1" class="reference"><a href="#cite_note-Yau_1994-4"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

</td></tr>

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<th><a href="Perihelion" class="mw-redirect" title="Perihelion">Perihelion</a><br>date</th>

<th><a href="Orbital_period" title="Orbital period">Orbital<br>period</a><br>(years)

</th></tr>

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<td>132.7

</td></tr>

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<td>134.6

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<td>136.2

</td></tr>

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<td>135.0

</td></tr>

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<td>131.7

</td></tr>

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<td>127.8

</td></tr>

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<td>130.5

</td></tr>

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<td>133.4

</td></tr>

<tr>

<td>135.0

</td></tr></tbody></table>

<p><b>Comet Swift–Tuttle</b> (formally designated <b>109P/Swift–Tuttle</b>) is a large <a href="List_of_periodic_comets" title="List of periodic comets">periodic</a> <a href="Comet" title="Comet">comet</a> with a 1995 (<a href="Osculating_orbit" title="Osculating orbit">osculating</a>) <a href="Orbital_period" title="Orbital period">orbital period</a> of 133 years that is in a 1:11 <a href="Orbital_resonance" title="Orbital resonance">orbital resonance</a> with <a href="Jupiter" title="Jupiter">Jupiter</a>. It fits the classical definition of a <a href="List_of_comets_by_type#List_of_Halley-type_comets" title="List of comets by type">Halley-type comet</a>, which has an <a href="Orbital_period" title="Orbital period">orbital period</a> between 20 and 200 years.<sup id="cite_ref-jpldata_7-0" class="reference"><a href="#cite_note-jpldata-7"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> The comet was independently discovered by <a href="Lewis_Swift" class="mw-redirect" title="Lewis Swift">Lewis Swift</a> on 16 July 1862 and by <a href="Horace_Parnell_Tuttle" title="Horace Parnell Tuttle">Horace Parnell Tuttle</a> on 19 July 1862.

</p><p>Its <a href="Comet_nucleus" title="Comet nucleus">nucleus</a> is 26 km (16 mi) in diameter.<sup id="cite_ref-jpldata_7-1" class="reference"><a href="#cite_note-jpldata-7"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Swift–Tuttle is the parent body of the <a href="Perseids" title="Perseids">Perseid</a> <a href="Meteor_shower" title="Meteor shower">meteor shower</a>, perhaps the best known shower and among the most reliable in performance.<sup id="cite_ref-Bedient_2010_8-0" class="reference"><a href="#cite_note-Bedient_2010-8"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup>

</p><p>The comet made a return appearance in 1992, when it was rediscovered by Japanese <a href="Astronomer" title="Astronomer">astronomer</a> Tsuruhiko Kiuchi and became visible with binoculars.<sup id="cite_ref-facts_9-0" class="reference"><a href="#cite_note-facts-9"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> It was last observed in April 1995 when it was 8.6 <a href="Astronomical_unit" title="Astronomical unit">AU</a> (1.3 <a href="1000000000_(number)" class="mw-redirect" title="1000000000 (number)">billion</a> <a href="Kilometre" title="Kilometre">km</a>) from the Sun.<sup id="cite_ref-MPC_2-1" class="reference"><a href="#cite_note-MPC-2"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> In 2126, it will be a bright naked-eye comet reaching an <a href="Apparent_magnitude" title="Apparent magnitude">apparent magnitude</a> of about 0.7.<sup id="cite_ref-Yau_1994_4-2" class="reference"><a href="#cite_note-Yau_1994-4"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="Historical_observations">Historical observations</h2></div>

<td colspan="8" style="text-align:center;"><b>Older passages</b><sup id="cite_ref-Yau_1994_4-3" class="reference"><a href="#cite_note-Yau_1994-4"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

</td></tr>

<tr>

<th>Date

</th></tr>

<tr>

<td>188-07-10

</td></tr>

<tr>

<td>–68-08-27

</td></tr>

<tr>

<td>–321-09-27

</td></tr></tbody></table>

<p>Chinese records indicate that, in 188, the comet reached <a href="Apparent_magnitude" title="Apparent magnitude">apparent magnitude</a> 0.1.<sup id="cite_ref-Yau_1994_4-4" class="reference"><a href="#cite_note-Yau_1994-4"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> Observation was also recorded in 69 <a href="Common_Era" title="Common Era">BCE</a>, and it was probably visible to the naked eye in 322 BCE.<sup id="cite_ref-Chambers_1995_10-0" class="reference"><a href="#cite_note-Chambers_1995-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>

</p><p>In the discovery year of 1862, the comet was as bright as <a href="Polaris" title="Polaris">Polaris</a>.<sup id="cite_ref-Levy_2008_11-0" class="reference"><a href="#cite_note-Levy_2008-11"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup>

</p><p>After the 1862 observations, it was incorrectly theorized that the comet would return between 1979 and 1983. However, it had been suggested in 1902 that this was the same comet as that observed by <a href="Ignaz_K%C3%B6gler" title="Ignaz Kögler">Ignatius Kegler</a> on 3 July 1737<sup id="cite_ref-Kronk_1999_12-0" class="reference"><a href="#cite_note-Kronk_1999-12"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> and on this basis <a href="Brian_G._Marsden" title="Brian G. Marsden">Brian Marsden</a> calculated correctly that it would return in 1992.<sup id="cite_ref-Chambers_1995_10-1" class="reference"><a href="#cite_note-Chambers_1995-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="Orbit">Orbit</h2></div>

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<p>The comet's perihelion is just under that of <a href="Earth" title="Earth">Earth</a>, while its aphelion is just over that of <a href="Pluto" title="Pluto">Pluto</a>. An unusual aspect of its orbit is that it was recently captured into a 1:11 <a href="Orbital_resonance" title="Orbital resonance">orbital resonance</a> with <a href="Jupiter" title="Jupiter">Jupiter</a>; it completes one orbit for every 11 of Jupiter.<sup id="cite_ref-Chambers_1995_10-2" class="reference"><a href="#cite_note-Chambers_1995-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> It was the first comet in a <a href="Retrograde_orbit" class="mw-redirect" title="Retrograde orbit">retrograde orbit</a> to be found in a resonance.<sup id="cite_ref-Chambers_1995_10-3" class="reference"><a href="#cite_note-Chambers_1995-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> In principle this would mean that its <a href="Proper_orbital_elements" title="Proper orbital elements">proper</a> long-term average period would be 130.48 years, as it <a href="Libration" title="Libration">librates</a> about the resonance. Over the short term, between <a href="Epoch_(astronomy)" title="Epoch (astronomy)">epochs</a> 1737 and 2126 the orbital period varies between 128 and 136 years.<sup id="cite_ref-MPC_2-2" class="reference"><a href="#cite_note-MPC-2"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> However, it only entered this resonance about 1000 years ago, and will probably exit the resonance in several thousand years.<sup id="cite_ref-Chambers_1995_10-4" class="reference"><a href="#cite_note-Chambers_1995-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading3"><h3 id="Threat_to_Earth">Threat to Earth</h3></div>

<p>The comet is on an <a href="Orbit" title="Orbit">orbit</a> that makes repeated close approaches to the <a href="Earth" title="Earth">Earth</a>–<a href="Moon" title="Moon">Moon</a> system,<sup id="cite_ref-Chambers_1995_10-5" class="reference"><a href="#cite_note-Chambers_1995-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> and has an Earth-MOID (<a href="Minimum_orbit_intersection_distance" title="Minimum orbit intersection distance">Minimum orbit intersection distance</a>) of 0.0009 AU (0.13 million km; 0.084 million mi).

<sup id="cite_ref-jpldata_7-2" class="reference"><a href="#cite_note-jpldata-7"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Upon its September 1992 rediscovery, the comet's date of <a href="Perihelion" class="mw-redirect" title="Perihelion">perihelion</a> passage was off from the 1973 prediction by 17 days.<sup id="cite_ref-ASP1993_13-0" class="reference"><a href="#cite_note-ASP1993-13"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> It was then noticed that if its next perihelion passage (July 2126) was also off by another 15 days (July 26), the comet could impact the Earth or the Moon on 14 August 2126.<sup id="cite_ref-IAUC_5636_14-0" class="reference"><a href="#cite_note-IAUC_5636-14"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup>

</p>

<p>Given the size of the nucleus of Swift–Tuttle, this was of some concern. This prompted amateur astronomer and writer <a href="Gary_W._Kronk" title="Gary W. Kronk">Gary W. Kronk</a> to search for previous apparitions of this comet. He found the comet was most likely observed by the Chinese at least twice, first in 69 BCE and later in 188 CE;<sup id="cite_ref-IAUC_5670_15-0" class="reference"><a href="#cite_note-IAUC_5670-15"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> these two sightings were quickly confirmed by Brian Marsden and added to the list of perihelion passages at the <a href="Minor_Planet_Center" title="Minor Planet Center">Minor Planet Center</a>.<sup id="cite_ref-MPC_2-3" class="reference"><a href="#cite_note-MPC-2"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Around 25 July 188 CE the comet passed about 0.129 AU (19.3 million km) from Earth.<sup id="cite_ref-Yau_1994_4-5" class="reference"><a href="#cite_note-Yau_1994-4"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

</p><p>This information and subsequent observations have led to recalculation of its orbit, which indicates the comet's orbit is sufficiently stable that there is absolutely no threat over the next two thousand years.<sup id="cite_ref-ASP1993_13-1" class="reference"><a href="#cite_note-ASP1993-13"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> It is now known that the comet will pass 0.153 AU (22.9 million km; 14.2 million mi) from Earth on August 5, 2126.<sup id="cite_ref-jpldata_7-3" class="reference"><a href="#cite_note-jpldata-7"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-uncertainty_16-0" class="reference"><a href="#cite_note-uncertainty-16"><span class="cite-bracket">[</span>b<span class="cite-bracket">]</span></a></sup> and within 0.147 AU (22.0 million km; 13.7 million mi) from Earth on August 24, 2261.<sup id="cite_ref-Yau_1994_4-6" class="reference"><a href="#cite_note-Yau_1994-4"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

</p>

<p>A close encounter with Earth is predicted for the comet's return to the inner Solar System in the year 3044, with the closest approach estimated to be 0.011 AU (1.0 million mi; 1.6 million km).<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> Another close encounter is predicted for the year 4479, around Sept. 15; the close approach is estimated to be less than 0.05 <a href="Astronomical_unit" title="Astronomical unit">AU</a>, with a probability of impact of 1 in a million.<sup id="cite_ref-Chambers_1995_10-6" class="reference"><a href="#cite_note-Chambers_1995-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> Subsequent to 4479, the orbital evolution of the comet is more difficult to predict; the probability of Earth impact per orbit is estimated as 2<span style="margin:0 .15em 0 .25em">×</span>10<sup>−8</sup> (0.000002%).<sup id="cite_ref-Chambers_1995_10-7" class="reference"><a href="#cite_note-Chambers_1995-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>

</p><p>Comet Swift–Tuttle is by far the largest <a href="Near-Earth_object" title="Near-Earth object">near-Earth object</a> (<a href="Apollo_asteroid" title="Apollo asteroid">Apollo</a> or <a href="Aten_asteroid" title="Aten asteroid">Aten</a> asteroid or <a href="Short-period_comet" class="mw-redirect" title="Short-period comet">short-period comet</a>) to cross Earth's orbit and make repeated close approaches to Earth.<sup id="cite_ref-jpldata_7-4" class="reference"><a href="#cite_note-jpldata-7"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> With a relative velocity of 60 km/s,<sup id="cite_ref-Weissman_2006_18-0" class="reference"><a href="#cite_note-Weissman_2006-18"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Verschuur_1997_19-0" class="reference"><a href="#cite_note-Verschuur_1997-19"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> an Earth impact would have an estimated energy of ~27 times that of the <a href="Chicxulub_crater#Impact_specifics" title="Chicxulub crater">Cretaceous–Paleogene impactor</a>.<sup id="cite_ref-K-T_impact_20-0" class="reference"><a href="#cite_note-K-T_impact-20"><span class="cite-bracket">[</span>c<span class="cite-bracket">]</span></a></sup> The comet has been described as "the single most dangerous object known to humanity".<sup id="cite_ref-Verschuur_1997_19-1" class="reference"><a href="#cite_note-Verschuur_1997-19"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> In 1996, the long-term possibility of Comet Swift–Tuttle impacting Earth was compared to <a href="433_Eros" title="433 Eros">433 Eros</a> and about 3000 other kilometer-sized objects of concern.<sup id="cite_ref-NYT-19960425_21-0" class="reference"><a href="#cite_note-NYT-19960425-21"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup>

</p><p>

</p>

<caption>Comet Swift–Tuttle Closest Earth Approach on 2126-Aug-05 15:50 UT<sup id="cite_ref-jpldata_7-5" class="reference"><a href="#cite_note-jpldata-7"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>

</caption>

<th>Date & time of<br>closest approach

</th>

<th>Earth distance<br>(<a href="Astronomical_unit" title="Astronomical unit">AU</a>)

</th>

<th>Sun distance<br>(AU)

</th>

<th>Velocity<br>wrt Earth<br>(km/s)

</th>

<th>Velocity<br>wrt Sun<br>(km/s)

</th>

<th>Uncertainty<br>region<br>(<a href="3-sigma" class="mw-redirect" title="3-sigma">3-sigma</a>)

</th>

<th>Reference

</th></tr>

<tr>

<td>0.15337 <a href="Astronomical_unit" title="Astronomical unit">AU</a> (22.944 million <a href="Kilometre" title="Kilometre">km</a>; 14.257 million <a href="Mile" title="Mile">mi</a>; 59.69 <a href="Lunar_distance_(astronomy)" class="mw-redirect" title="Lunar distance (astronomy)">LD</a>)</td>

<td>1.04 AU (156 million km; 97 million mi; 400 LD)</td>

<td><small><a rel="nofollow" class="external text" href="https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%27DES%3D109P%3BCAP%27&START_TIME=%272126-08-05%2015:50%27&STOP_TIME=%272126-08-06%27&STEP_SIZE=%271%20day%27&QUANTITIES=%2719,20,22,39%27">Horizons</a></small>

</td></tr></tbody></table>

<ul><li><a href="Lists_of_comets" title="Lists of comets">Lists of comets</a></li>

<li><a href="List_of_interstellar_comets" class="mw-redirect" title="List of interstellar comets">List of interstellar comets</a></li>

<li><a href="List_of_comets_by_type" title="List of comets by type">List of comets by type</a></li>

<li><a href="List_of_non-periodic_comets" class="mw-redirect" title="List of non-periodic comets">List of non-periodic comets</a></li>

<li><a href="List_of_periodic_comets" title="List of periodic comets">List of periodic comets</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2></div>

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<li id="cite_note-speed-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-speed_1-0">^</a></b></span> <span class="reference-text"><span class="nowrap"><i>v</i> = 42.1219 <span class="nowrap">√<span style="border-top:1px solid; padding:0 0.1em;">1/<i>r</i> − 0.5/<i>a</i></span></span></span>, where <i>r</i> is the distance from the Sun, and <i>a</i> is the <a href="Semi-major_and_semi-minor_axes" title="Semi-major and semi-minor axes">semimajor axis</a>.</span>

</li>

<li id="cite_note-uncertainty-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-uncertainty_16-0">^</a></b></span> <span class="reference-text">The <a href="3-sigma" class="mw-redirect" title="3-sigma">3-sigma</a> uncertainty in the comet's closest approach to Earth on 5 August 2126 is about <a rel="nofollow" class="external text" href="https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%27DES%3D109P%3BCAP%27&START_TIME=%272126-08-05%2015:50%27&STOP_TIME=%272126-08-06%27&STEP_SIZE=%271%20day%27&QUANTITIES=%2720,39%27">±10 thousand km.</a></span>

</li>

<li id="cite_note-K-T_impact-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-K-T_impact_20-0">^</a></b></span> <span class="reference-text">This calculation can be carried out in the manner given by Weissman for <a href="Comet_Hale%E2%80%93Bopp" title="Comet Hale–Bopp">Comet Hale–Bopp</a>, as follows: A radius of 13.5 km and an estimated density of 0.6 g/cm<sup>3</sup> gives a cometary mass of 6.2<span style="margin:0 .15em 0 .25em">×</span>10<sup><span class="nowrap">18</span></sup> g. An encounter velocity of 60 km/s yields an impact velocity of 61 km/s, giving an impact energy of 1.15<span style="margin:0 .15em 0 .25em">×</span>10<sup><span class="nowrap">32</span></sup> <a href="Erg" title="Erg">ergs</a>, or 2.75<span style="margin:0 .15em 0 .25em">×</span>10<sup><span class="nowrap">9</span></sup> <a href="TNT_equivalent" title="TNT equivalent">megatons</a>, about 27.5 times the estimated energy of the <a href="Alvarez_hypothesis" title="Alvarez hypothesis">K–T impact event</a>.</span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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/* end https://en.wikipedia.org/ */

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<li id="cite_note-NK723-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-NK723_3-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFNakano1999" class="citation web cs1"><a href="Syuichi_Nakano" class="mw-redirect" title="Syuichi Nakano">Nakano, Syuichi</a> (1999-11-18). <a rel="nofollow" class="external text" href="http://oaa.gr.jp/~oaacs/nk/nk723.htm">"109P/Swift–Tuttle (NK 798)"</a>. OAA Computing and Minor Planet Sections<span class="reference-accessdate">. Retrieved <span class="nowrap">2011-05-09</span></span>.</cite></span>

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<li id="cite_note-Yau_1994-4"><span class="mw-cite-backlink">^ <a href="#cite_ref-Yau_1994_4-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Yau_1994_4-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Yau_1994_4-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Yau_1994_4-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Yau_1994_4-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Yau_1994_4-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Yau_1994_4-6"><sup><i><b>g</b></i></sup></a></span> <span class="reference-text"><cite id="CITEREFK._YauD._K._YeomansP._Weissman1994" class="citation journal cs1">K. Yau; D. K. Yeomans; P. Weissman (1994). <a rel="nofollow" class="external text" href="https://academic.oup.com/mnras/article-pdf/266/2/305/3098032/mnras266-0305.pdf">"The Past and Future Motion of Comet P/Swift-Tuttle"</a> <span class="cs1-format">(PDF)</span>. <i>Monthly Notices of the Royal Astronomical Society</i>. <b>266</b> (2): <span class="nowrap">305–</span>316. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1994MNRAS.266..305Y">1994MNRAS.266..305Y</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1093%2Fmnras%2F266.2.305">10.1093/mnras/266.2.305</a></span>.</cite></span>

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<li id="cite_note-McDavid_1995-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-McDavid_1995_5-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFD._McDavidD._C._Boice1995" class="citation journal cs1">D. McDavid; D. C. Boice (1995). "The Rotation Period of Comet P/Swift–Tuttle". <i>Bulletin of the American Astronomical Society</i>. <b>27</b>: 1338. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1995AAS...187.4209M">1995AAS...187.4209M</a>.</cite></span>

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<li id="cite_note-Lamy_2004-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-Lamy_2004_6-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFP._L._LamyI._TothY._R._FernándezH._A._Weaver2004" class="citation book cs1">P. L. Lamy; I. Toth; Y. R. Fernández; H. A. Weaver (2004). <a rel="nofollow" class="external text" href="https://physics.ucf.edu/~yfernandez/papers/comets2chapter/comets2reprint.pdf">"The Sizes, Shapes, Albedos, and Colors of Cometary Nuclei"</a> <span class="cs1-format">(PDF)</span>. <i>Comets II</i>. pp. <span class="nowrap">223–</span>264. <a href="JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a> <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/j.ctv1v7zdq5.22">j.ctv1v7zdq5.22</a>.</cite></span>

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<li id="cite_note-jpldata-7"><span class="mw-cite-backlink">^ <a href="#cite_ref-jpldata_7-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-jpldata_7-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-jpldata_7-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-jpldata_7-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-jpldata_7-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-jpldata_7-5"><sup><i><b>f</b></i></sup></a></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=109P">"109P/Swift–Tuttle – JPL Small-Body Database Lookup"</a>. <i>ssd.jpl.nasa.gov</i>. <a href="Jet_Propulsion_Laboratory" title="Jet Propulsion Laboratory">Jet Propulsion Laboratory</a><span class="reference-accessdate">. Retrieved <span class="nowrap">9 May</span> 2011</span>.</cite></span>

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<li id="cite_note-Bedient_2010-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-Bedient_2010_8-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFJ._Bedient2010" class="citation web cs1">J. Bedient (20 June 2010). <a rel="nofollow" class="external text" href="http://www.amsmeteors.org/showers.html">"Meteor Showers"</a>. <a href="American_Meteor_Society" title="American Meteor Society">American Meteor Society</a><span class="reference-accessdate">. Retrieved <span class="nowrap">31 July</span> 2010</span>.</cite></span>

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<li id="cite_note-facts-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-facts_9-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFBritt2005" class="citation news cs1">Britt, Robert (2005-08-11). <a rel="nofollow" class="external text" href="http://www.space.com/spacewatch/050811_perseid_facts.html">"Top 10 Perseid Meteor Shower Facts"</a>. <a href="Space.com" title="Space.com">Space.com</a><span class="reference-accessdate">. Retrieved <span class="nowrap">2009-08-10</span></span>.</cite></span>

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<li id="cite_note-Chambers_1995-10"><span class="mw-cite-backlink">^ <a href="#cite_ref-Chambers_1995_10-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Chambers_1995_10-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Chambers_1995_10-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Chambers_1995_10-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Chambers_1995_10-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Chambers_1995_10-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Chambers_1995_10-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Chambers_1995_10-7"><sup><i><b>h</b></i></sup></a></span> <span class="reference-text"><cite id="CITEREFJ._E._Chambers1995" class="citation journal cs1">J. E. Chambers (1995). "The long-term dynamical evolution of Comet Swift–Tuttle". <i><a href="Icarus_(journal)" title="Icarus (journal)">Icarus</a></i>. <b>114</b> (2): <span class="nowrap">372–</span>386. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1995Icar..114..372C">1995Icar..114..372C</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1006%2Ficar.1995.1069">10.1006/icar.1995.1069</a>.</cite></span>

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<li id="cite_note-Levy_2008-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-Levy_2008_11-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFD._H._Levy2008" class="citation book cs1">D. H. Levy (2008). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=jAr7HMnlPGUC&pg=PA12"><i>David Levy's Guide to Observing Meteor Showers</i></a>. Cambridge University Press. p. 12. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-521-69691-3</bdi>.</cite></span>

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<li id="cite_note-Kronk_1999-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-Kronk_1999_12-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFG._W._KronkM._MeyerD._A._J._Seargent1999" class="citation book cs1 cs1-prop-long-vol">G. W. Kronk; M. Meyer; D. A. J. Seargent (1999). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=UzeqxQEACAAJ&pg=PA400"><i>Cometography: A Catalog of Comets</i></a>. Vol. 1: Ancient–1799. <a href="Cambridge_University_Press" title="Cambridge University Press">Cambridge University Press</a>. pp. <span class="nowrap">400–</span>402. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-521-58504-0</bdi>.</cite></span>

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<li id="cite_note-ASP1993-13"><span class="mw-cite-backlink">^ <a href="#cite_ref-ASP1993_13-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-ASP1993_13-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><cite id="CITEREFStephens1993" class="citation web cs1">Stephens, Sally (1993). <a rel="nofollow" class="external text" href="http://www.as.wvu.edu/~jel/skywatch/swfttle.html">"on Swift–Tuttle's possible collision"</a>. <a href="Astronomical_Society_of_the_Pacific" title="Astronomical Society of the Pacific">Astronomical Society of the Pacific</a>. <a rel="nofollow" class="external text" href="https://archive.today/20120525195932/http://www.as.wvu.edu/~jel/skywatch/swfttle.html">Archived</a> from the original on 2012-05-25<span class="reference-accessdate">. Retrieved <span class="nowrap">2008-08-25</span></span>.</cite></span>

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<li id="cite_note-IAUC_5636-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-IAUC_5636_14-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFB._G._MarsdenS._Nakano1992" class="citation web cs1">B. G. Marsden; S. Nakano (15 October 1992). <a rel="nofollow" class="external text" href="http://www.cbat.eps.harvard.edu/iauc/05600/05636.html">"Periodic Comet Swift–Tuttle (1992t)"</a>. <i>IAU Circular</i>.</cite></span>

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<li id="cite_note-IAUC_5670-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-IAUC_5670_15-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFB._G._MarsdenR._HaverL._KohoutekG._Waddington1992" class="citation journal cs1">B. G. Marsden; R. Haver; L. Kohoutek; G. Waddington; G. W. Kronk (5 December 1992). <a rel="nofollow" class="external text" href="http://www.cbat.eps.harvard.edu/iauc/05600/05670.html">"Periodic Comet Swift–Tuttle (1992t)"</a>. <i>IAU Circular</i>. <b>5670</b> (1).</cite></span>

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<li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20121219103151/http://astrosociety.org/edu/publications/tnl/23/23.html">"ASP: Cosmic Collisions"</a>. Archived from <a rel="nofollow" class="external text" href="https://astrosociety.org/edu/publications/tnl/23/23.html">the original</a> on 2012-12-19.</cite></span>

</li>

<li id="cite_note-Weissman_2006-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-Weissman_2006_18-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFP._R._Weissman2006" class="citation conference cs1">P. R. Weissman (2006). A. Milani; G. B. Valsecchi; D. Vokrouhlicky (eds.). <a rel="nofollow" class="external text" href="https://www.cambridge.org/core/services/aop-cambridge-core/content/view/B828FD4A518E482CA91ADBACDCE70448/S1743921307003559a.pdf/the-cometary-impactor-flux-at-the-earth.pdf"><i>The Cometary Impactor Flux at the Earth</i></a> <span class="cs1-format">(PDF)</span>. Near Earth Objects, our Celestial Neighbors: Opportunity and Risk; IAU Symposium No. 236. <i><a href="Proceedings_of_the_International_Astronomical_Union" class="mw-redirect" title="Proceedings of the International Astronomical Union">Proceedings of the International Astronomical Union</a></i>. Vol. 2, no. 236. pp. <span class="nowrap">441–</span>450. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1017%2FS1743921307003559">10.1017/S1743921307003559</a></span>.</cite></span>

</li>

<li id="cite_note-Verschuur_1997-19"><span class="mw-cite-backlink">^ <a href="#cite_ref-Verschuur_1997_19-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Verschuur_1997_19-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><cite id="CITEREFG._L._Verschuur1997" class="citation book cs1">G. L. Verschuur (1997). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=4gnumbZdVqEC&pg=PA216"><i>Impact!: The Threat of Comets and Asteroids</i></a>. <a href="Oxford_University_Press" title="Oxford University Press">Oxford University Press</a>. p. 216. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-19-511919-0</bdi>.</cite></span>

</li>

<li id="cite_note-NYT-19960425-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-NYT-19960425_21-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFM._W._Browne1996" class="citation news cs1">M. W. Browne (25 April 1996). <a rel="nofollow" class="external text" href="https://www.nytimes.com/1996/04/25/us/mathematicians-say-asteroid-may-hit-earth-in-a-million-years.html">"Mathematicians Say Asteroid May Hit Earth in a Million Years"</a>. <i><a href="The_New_York_Times" title="The New York Times">The New York Times</a></i><span class="reference-accessdate">. Retrieved <span class="nowrap">16 November</span> 2018</span>.</cite></span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="Bibliography">Bibliography</h2></div>

<ul><li><cite id="CITEREFSiegel2016" class="citation web cs1">Siegel, Ethan (2016-08-11). <a rel="nofollow" class="external text" href="https://www.forbes.com/sites/startswithabang/2016/08/11/the-most-dangerous-object-known-to-humanity">"The Most Dangerous Object Known To Humanity"</a>. <i><a href="Forbes" title="Forbes">Forbes</a></i>.</cite></li></ul>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

<ul><li><a rel="nofollow" class="external text" href="http://www.minorplanetcenter.net/db_search/show_object?object_id=109P">109P/Swift-Tuttle</a> at the <a href="Minor_Planet_Center" title="Minor Planet Center">Minor Planet Center</a>'s Database</li>

<li><a rel="nofollow" class="external text" href="https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=1000140">Comet Swift–Tuttle</a> at the <i><a href="JPL_Small-Body_Database" title="JPL Small-Body Database">JPL Small-Body Database</a></i></li>

<li><a rel="nofollow" class="external text" href="https://apod.nasa.gov/apod/ap960219.html">NASA Astronomy Picture of the Day: Periodic Comet Swift–Tuttle (19 February 1996)</a></li></ul>

<p><br>

</p>

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</style><div id="Comets119" style="font-size:114%;margin:0 4em"><a href="Comet" title="Comet">Comets</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;">Features</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Comet_nucleus" title="Comet nucleus">Nucleus</a></li>

<li><a href="Comet_tail" title="Comet tail">Tails</a></li>

<li><a href="Antitail" class="mw-redirect" title="Antitail">Antitail</a></li>

<li><a href="Comet_dust" title="Comet dust">Comet dust</a></li>

<li><a href="Meteor_shower" title="Meteor shower">Meteor shower</a></li></ul>

</div></td><td class="noviewer navbox-image" rowspan="6" style="width:1px;padding:0 0 0 2px"><div><span typeof="mw:File"></span><br><span typeof="mw:File"></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;"><a href="Comet#Orbital_characteristics" title="Comet">Types</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="List_of_periodic_comets" title="List of periodic comets">Periodic</a>

<ul><li><a href="List_of_numbered_comets" title="List of numbered comets">Numbered</a></li>

<li><a href="List_of_long-period_comets" title="List of long-period comets">Long period</a></li>

<li><a href="List_of_Halley-type_comets" title="List of Halley-type comets">Halley-type</a></li>

<li><a href="Jupiter-family_comet" class="mw-redirect" title="Jupiter-family comet">Jupiter-family</a></li>

<li>Encke-type</li>

<li><a href="List_of_non-periodic_comets" class="mw-redirect" title="List of non-periodic comets">Non-periodic</a>

<ul><li><a href="List_of_near-parabolic_comets" title="List of near-parabolic comets">Near-parabolic</a></li>

<li><a href="List_of_hyperbolic_comets" class="mw-redirect" title="List of hyperbolic comets">Hyperbolic</a></li>

<li><a href="List_of_comets_with_no_meaningful_orbit" title="List of comets with no meaningful orbit">Unknown-orbit</a></li></ul></li>

<li><a href="Great_comet" title="Great comet">Great Comet</a></li>

<li><a href="Sungrazing_comet" title="Sungrazing comet">Sungrazing</a> (<a href="Kreutz_sungrazer" title="Kreutz sungrazer">Kreutz</a>)</li>

<li><a href="Extinct_comet" title="Extinct comet">Extinct</a></li>

<li><a href="Exocomet" title="Exocomet">Exocomet</a></li>

<li><a href="Interstellar_object" title="Interstellar object">Interstellar</a></li>

<li><a href="Dark_comet" title="Dark comet">Dark comet</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;">Related</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Naming_of_comets" title="Naming of comets">Naming of comets</a></li>

<li><a href="Observational_history_of_comets" title="Observational history of comets">Observational history of comets</a></li>

<li><a href="Centaur_(minor_planet)" class="mw-redirect" title="Centaur (minor planet)">Centaur</a></li>

<li>Comet discoverers

<ul><li><a href="List_of_comets_discovered_by_the_LINEAR_project" title="List of comets discovered by the LINEAR project">LINEAR</a></li></ul></li>

<li><a href="Extraterrestrial_atmosphere" title="Extraterrestrial atmosphere">Extraterrestrial atmosphere</a></li>

<li><a href="Oort_cloud" title="Oort cloud">Oort cloud</a></li>

<li><a href="Small_Solar_System_body" title="Small Solar System body">Small Solar System body</a></li>

<li><a href="Asteroid" title="Asteroid">Asteroid</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;">Exploration</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="List_of_missions_to_comets" title="List of missions to comets">List of missions to comets</a></li>

<li><a href="List_of_comets_visited_by_spacecraft" class="mw-redirect" title="List of comets visited by spacecraft">List of comets visited by spacecraft</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;">Latest</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="C/2024_S1_(ATLAS)" title="C/2024 S1 (ATLAS)">C/2024 S1 (ATLAS)</a></li>

<li><a href="C/2024_G3_(ATLAS)" title="C/2024 G3 (ATLAS)">C/2024 G3 (ATLAS)</a></li>

<li><a href="C/2023_P1_(Nishimura)" title="C/2023 P1 (Nishimura)">C/2023 P1 (Nishimura)</a></li>

<li><a href="C/2023_H2_(Lemmon)" title="C/2023 H2 (Lemmon)">C/2023 H2 (Lemmon)</a></li>

<li><a href="C/2023_E1_(ATLAS)" title="C/2023 E1 (ATLAS)">C/2023 E1 (ATLAS)</a></li>

<li><a href="C/2023_A3_(Tsuchinshan%E2%80%93ATLAS)" title="C/2023 A3 (Tsuchinshan–ATLAS)">C/2023 A3 (Tsuchinshan–ATLAS)</a></li>

<li><a href="C/2021_O3_(PanSTARRS)" title="C/2021 O3 (PanSTARRS)">C/2021 O3 (PanSTARRS)</a></li>

<li><a href="C/2021_J1_(Maury-Attard)" class="mw-redirect" title="C/2021 J1 (Maury-Attard)">C/2021 J1 (Maury-Attard)</a></li>

<li><a href="C/2021_A1_(Leonard)" title="C/2021 A1 (Leonard)">C/2021 A1 (Leonard)</a></li>

<li><a href="C/2020_F5_(MASTER)" title="C/2020 F5 (MASTER)">C/2020 F5 (MASTER)</a></li>

<li><a href="Comet_NEOWISE" title="Comet NEOWISE">C/2020 F3 (NEOWISE)</a></li>

<li><a href="C/2019_Y4_(ATLAS)" title="C/2019 Y4 (ATLAS)">C/2019 Y4 (ATLAS)</a></li>

<li><a href="C/2019_Y1_(ATLAS)" title="C/2019 Y1 (ATLAS)">C/2019 Y1 (ATLAS)</a></li>

<li><a href="C/2019_U6_(Lemmon)" title="C/2019 U6 (Lemmon)">C/2019 U6 (Lemmon)</a></li>

<li><a href="2I/Borisov" title="2I/Borisov">2I/Borisov</a></li>

<li><a href="P/2019_LD2_(ATLAS)" title="P/2019 LD2 (ATLAS)">P/2019 LD2 (ATLAS)</a></li>

<li><a href="C/2018_Y1_(Iwamoto)" title="C/2018 Y1 (Iwamoto)">C/2018 Y1 (Iwamoto)</a></li>

<li><a href="C/2018_C2_(Lemmon)" title="C/2018 C2 (Lemmon)">C/2018 C2 (Lemmon)</a></li>

<li><a href="C/2017_K2_(PanSTARRS)" title="C/2017 K2 (PanSTARRS)">C/2017 K2 (PanSTARRS)</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;">Culture and<br>speculation</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Antimatter_comet" title="Antimatter comet">Antimatter comet</a></li>

<li><a href="Comets_in_fiction" title="Comets in fiction">Comets in fiction</a></li>

<li><a href="Comet_vintages" title="Comet vintages">Comet vintages</a></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2" style="text-align: center;"><div id="Lists_of_comets_(more)119" style="font-size:114%;margin:0 4em"><a href="Lists_of_comets" title="Lists of comets">Lists of comets</a> (more)</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;"><a href="List_of_numbered_comets" title="List of numbered comets">Periodic<br>comets</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;">Until 1985<br>(all)</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Halley's_Comet" title="Halley's Comet">1P/Halley</a></li>

<li><a href="Comet_Encke" title="Comet Encke">2P/Encke</a></li>

<li><a href="Biela's_Comet" title="Biela's Comet">3D/Biela</a></li>

<li><a href="5D/Brorsen" title="5D/Brorsen">5D/Brorsen</a></li>

<li><a href="6P/d'Arrest" title="6P/d'Arrest">6P/d'Arrest</a></li>

<li><a href="7P/Pons%E2%80%93Winnecke" title="7P/Pons–Winnecke">7P/Pons–Winnecke</a></li>

<li><a href="8P/Tuttle" title="8P/Tuttle">8P/Tuttle</a></li>

<li><a href="Tempel_1" title="Tempel 1">9P/Tempel</a></li>

<li><a href="10P/Tempel" title="10P/Tempel">10P/Tempel</a></li>

<li><a href="11P/Tempel%E2%80%93Swift%E2%80%93LINEAR" title="11P/Tempel–Swift–LINEAR">11P/Tempel–Swift–LINEAR</a></li>

<li><a href="12P/Pons%E2%80%93Brooks" title="12P/Pons–Brooks">12P/Pons–Brooks</a></li>

<li><a href="13P/Olbers" title="13P/Olbers">13P/Olbers</a></li>

<li><a href="15P/Finlay" title="15P/Finlay">15P/Finlay</a></li>

<li><a href="16P/Brooks" title="16P/Brooks">16P/Brooks</a></li>

<li><a href="Comet_Holmes" title="Comet Holmes">17P/Holmes</a></li>

<li><a href="18D/Perrine%E2%80%93Mrkos" title="18D/Perrine–Mrkos">18D/Perrine–Mrkos</a></li>

<li><a href="19P/Borrelly" title="19P/Borrelly">19P/Borrelly</a></li>

<li><a href="20D/Westphal" title="20D/Westphal">20D/Westphal</a></li>

<li><a href="21P/Giacobini%E2%80%93Zinner" title="21P/Giacobini–Zinner">21P/Giacobini–Zinner</a></li>

<li><a href="22P/Kopff" title="22P/Kopff">22P/Kopff</a></li>

<li><a href="23P/Brorsen%E2%80%93Metcalf" title="23P/Brorsen–Metcalf">23P/Brorsen–Metcalf</a></li>

<li><a href="24P/Schaumasse" title="24P/Schaumasse">24P/Schaumasse</a></li>

<li><a href="25D/Neujmin" title="25D/Neujmin">25D/Neujmin</a></li>

<li><a href="26P/Grigg%E2%80%93Skjellerup" title="26P/Grigg–Skjellerup">26P/Grigg–Skjellerup</a></li>

<li><a href="27P/Crommelin" title="27P/Crommelin">27P/Crommelin</a></li>

<li><a href="28P/Neujmin" title="28P/Neujmin">28P/Neujmin</a></li>

<li><a href="29P/Schwassmann%E2%80%93Wachmann" title="29P/Schwassmann–Wachmann">29P/Schwassmann–Wachmann</a></li>

<li><a href="30P/Reinmuth" title="30P/Reinmuth">30P/Reinmuth</a></li>

<li><a href="31P/Schwassmann%E2%80%93Wachmann" title="31P/Schwassmann–Wachmann">31P/Schwassmann–Wachmann</a></li>

<li><a href="32P/Comas_Sol%C3%A0" title="32P/Comas Solà">32P/Comas Solà</a></li>

<li><a href="33P/Daniel" title="33P/Daniel">33P/Daniel</a></li>

<li><a href="35P/Herschel%E2%80%93Rigollet" title="35P/Herschel–Rigollet">35P/Herschel–Rigollet</a></li>

<li><a href="36P/Whipple" title="36P/Whipple">36P/Whipple</a></li>

<li><a href="37P/Forbes" title="37P/Forbes">37P/Forbes</a></li>

<li><a href="38P/Stephan%E2%80%93Oterma" title="38P/Stephan–Oterma">38P/Stephan–Oterma</a></li>

<li><a href="39P/Oterma" title="39P/Oterma">39P/Oterma</a></li>

<li><a href="40P/V%C3%A4is%C3%A4l%C3%A4" title="40P/Väisälä">40P/Väisälä</a></li>

<li><a href="41P/Tuttle%E2%80%93Giacobini%E2%80%93Kres%C3%A1k" title="41P/Tuttle–Giacobini–Kresák">41P/Tuttle–Giacobini–Kresák</a></li>

<li><a href="42P/Neujmin" title="42P/Neujmin">42P/Neujmin</a></li>

<li><a href="43P/Wolf%E2%80%93Harrington" title="43P/Wolf–Harrington">43P/Wolf–Harrington</a></li>

<li><a href="44P/Reinmuth" title="44P/Reinmuth">44P/Reinmuth</a></li>

<li><a href="45P/Honda%E2%80%93Mrkos%E2%80%93Pajdu%C5%A1%C3%A1kov%C3%A1" title="45P/Honda–Mrkos–Pajdušáková">45P/Honda–Mrkos–Pajdušáková</a></li>

<li><a href="46P/Wirtanen" title="46P/Wirtanen">46P/Wirtanen</a></li>

<li><a href="47P/Ashbrook%E2%80%93Jackson" title="47P/Ashbrook–Jackson">47P/Ashbrook–Jackson</a></li>

<li><a href="48P/Johnson" title="48P/Johnson">48P/Johnson</a></li>

<li><a href="49P/Arend%E2%80%93Rigaux" title="49P/Arend–Rigaux">49P/Arend–Rigaux</a></li>

<li><a href="50P/Arend" title="50P/Arend">50P/Arend</a></li>

<li><a href="51P/Harrington" title="51P/Harrington">51P/Harrington</a></li>

<li><a href="52P/Harrington%E2%80%93Abell" title="52P/Harrington–Abell">52P/Harrington–Abell</a></li>

<li><a href="53P/Van_Biesbroeck" title="53P/Van Biesbroeck">53P/Van Biesbroeck</a></li>

<li><a href="54P/de_Vico%E2%80%93Swift%E2%80%93NEAT" title="54P/de Vico–Swift–NEAT">54P/de Vico–Swift–NEAT</a></li>

<li><a href="55P/Tempel%E2%80%93Tuttle" title="55P/Tempel–Tuttle">55P/Tempel–Tuttle</a></li>

<li><a href="56P/Slaughter%E2%80%93Burnham" title="56P/Slaughter–Burnham">56P/Slaughter–Burnham</a></li>

<li><a href="57P/du_Toit%E2%80%93Neujmin%E2%80%93Delporte" title="57P/du Toit–Neujmin–Delporte">57P/du Toit–Neujmin–Delporte</a></li>

<li><a href="58P/Jackson%E2%80%93Neujmin" title="58P/Jackson–Neujmin">58P/Jackson–Neujmin</a></li>

<li><a href="59P/Kearns%E2%80%93Kwee" title="59P/Kearns–Kwee">59P/Kearns–Kwee</a></li>

<li><a href="60P/Tsuchinshan" title="60P/Tsuchinshan">60P/Tsuchinshan</a></li>

<li><a href="61P/Shajn%E2%80%93Schaldach" title="61P/Shajn–Schaldach">61P/Shajn–Schaldach</a></li>

<li><a href="62P/Tsuchinshan" title="62P/Tsuchinshan">62P/Tsuchinshan</a></li>

<li><a href="64P/Swift%E2%80%93Gehrels" title="64P/Swift–Gehrels">64P/Swift–Gehrels</a></li>

<li><a href="67P/Churyumov%E2%80%93Gerasimenko" title="67P/Churyumov–Gerasimenko">67P/Churyumov–Gerasimenko</a></li>

<li><a href="68P/Klemola" title="68P/Klemola">68P/Klemola</a></li>

<li><a href="69P/Taylor" title="69P/Taylor">69P/Taylor</a></li>

<li><a href="70P/Kojima" title="70P/Kojima">70P/Kojima</a></li>

<li><a href="71P/Clark" title="71P/Clark">71P/Clark</a></li>

<li><a href="72P/Denning%E2%80%93Fujikawa" title="72P/Denning–Fujikawa">72P/Denning–Fujikawa</a></li>

<li><a href="73P/Schwassmann%E2%80%93Wachmann" title="73P/Schwassmann–Wachmann">73P/Schwassmann–Wachmann</a></li>

<li><a href="74P/Smirnova%E2%80%93Chernykh" title="74P/Smirnova–Chernykh">74P/Smirnova–Chernykh</a></li>

<li><a href="75D/Kohoutek" title="75D/Kohoutek">75D/Kohoutek</a></li>

<li><a href="76P/West%E2%80%93Kohoutek%E2%80%93Ikemura" title="76P/West–Kohoutek–Ikemura">76P/West–Kohoutek–Ikemura</a></li>

<li><a href="77P/Longmore" title="77P/Longmore">77P/Longmore</a></li>

<li><a href="78P/Gehrels" title="78P/Gehrels">78P/Gehrels</a></li>

<li><a href="79P/du_Toit%E2%80%93Hartley" title="79P/du Toit–Hartley">79P/du Toit–Hartley</a></li>

<li><a href="80P/Peters%E2%80%93Hartley" title="80P/Peters–Hartley">80P/Peters–Hartley</a></li>

<li><a href="82P/Gehrels" title="82P/Gehrels">82P/Gehrels</a></li>

<li><a href="83D/Russell" title="83D/Russell">83D/Russell</a></li>

<li><a href="84P/Giclas" title="84P/Giclas">84P/Giclas</a></li>

<li><a href="85D/Boethin" title="85D/Boethin">85D/Boethin</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;">After 1985<br>(notable)</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="88P/Howell" title="88P/Howell">88P/Howell</a></li>

<li><a href="92P/Sanguin" title="92P/Sanguin">92P/Sanguin</a></li>

<li><a href="96P/Machholz" title="96P/Machholz">96P/Machholz</a></li>

<li><a href="97P/Metcalf%E2%80%93Brewington" title="97P/Metcalf–Brewington">97P/Metcalf–Brewington</a></li>

<li><a href="103P/Hartley" title="103P/Hartley">103P/Hartley</a></li>

<li><a href="4015_Wilson%E2%80%93Harrington" title="4015 Wilson–Harrington">107P/Wilson–Harrington</a></li>

<li><a href="108P/Ciffr%C3%A9o" title="108P/Ciffréo">108P/Ciffréo</a></li>

<li><a href="141P/Machholz" title="141P/Machholz">141P/Machholz</a></li>

<li><a href="144P/Kushida" title="144P/Kushida">144P/Kushida</a></li>

<li><a href="147P/Kushida%E2%80%93Muramatsu" title="147P/Kushida–Muramatsu">147P/Kushida–Muramatsu</a></li>

<li><a href="153P/Ikeya%E2%80%93Zhang" title="153P/Ikeya–Zhang">153P/Ikeya–Zhang</a></li>

<li><a href="156P/Russell%E2%80%93LINEAR" title="156P/Russell–LINEAR">156P/Russell–LINEAR</a></li>

<li><a href="161P/Hartley%E2%80%93IRAS" title="161P/Hartley–IRAS">161P/Hartley–IRAS</a></li>

<li><a href="162P/Siding_Spring" title="162P/Siding Spring">162P/Siding Spring</a></li>

<li><a href="168P/Hergenrother" title="168P/Hergenrother">168P/Hergenrother</a></li>

<li><a href="177P/Barnard" title="177P/Barnard">177P/Barnard</a></li>

<li><a href="205P/Giacobini" title="205P/Giacobini">205P/Giacobini</a></li>

<li><a href="209P/LINEAR" title="209P/LINEAR">209P/LINEAR</a></li>

<li><a href="249P/LINEAR" title="249P/LINEAR">249P/LINEAR</a></li>

<li><a href="252P/LINEAR" title="252P/LINEAR">252P/LINEAR</a></li>

<li><a href="273P/Pons%E2%80%93Gambart" title="273P/Pons–Gambart">273P/Pons–Gambart</a></li>

<li><a href="289P/Blanpain" title="289P/Blanpain">289P/Blanpain</a></li>

<li><a href="311P/PanSTARRS" title="311P/PanSTARRS">311P/PanSTARRS</a></li>

<li><a href="332P/Ikeya%E2%80%93Murakami" title="332P/Ikeya–Murakami">332P/Ikeya–Murakami</a></li>

<li><a href="333P/LINEAR" title="333P/LINEAR">333P/LINEAR</a></li>

<li><a href="354P/LINEAR" title="354P/LINEAR">354P/LINEAR</a></li>

<li><a href="460P/PanSTARRS" title="460P/PanSTARRS">460P/PanSTARRS</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;"><a href="Asteroid#Terminology" title="Asteroid">Comet-like<br>asteroids</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="596_Scheila" title="596 Scheila">596 Scheila</a></li>

<li><a href="2060_Chiron" title="2060 Chiron">2060 Chiron</a> (95P)</li>

<li><a href="4015_Wilson%E2%80%93Harrington" title="4015 Wilson–Harrington">4015 Wilson–Harrington</a> (107P)</li>

<li><a href="7968_Elst%E2%80%93Pizarro" title="7968 Elst–Pizarro">7968 Elst–Pizarro</a> (133P)</li>

<li><a href="165P/LINEAR" title="165P/LINEAR">165P/LINEAR</a></li>

<li><a href="167P/CINEOS" title="167P/CINEOS">167P/CINEOS</a></li>

<li><a href="60558_Echeclus" title="60558 Echeclus">60558 Echeclus</a> (174P)</li>

<li><a href="118401_LINEAR" title="118401 LINEAR">118401 LINEAR</a> (176P)</li>

<li><a href="259P/Garradd" title="259P/Garradd">259P/Garradd</a></li>

<li><a href="311P/PanSTARRS" title="311P/PanSTARRS">311P/PanSTARRS</a></li>

<li><a href="324P/La_Sagra" title="324P/La Sagra">324P/La Sagra</a></li>

<li><a href="331P/Gibbs" title="331P/Gibbs">331P/Gibbs</a></li>

<li><a href="354P/LINEAR" title="354P/LINEAR">354P/LINEAR</a></li>

<li><a href="358P/PANSTARRS" class="mw-redirect" title="358P/PANSTARRS">358P/PANSTARRS</a></li>

<li><a href="P/2013_R3_(Catalina-PANSTARRS)" class="mw-redirect" title="P/2013 R3 (Catalina-PANSTARRS)">P/2013 R3 (Catalina-PANSTARRS)</a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;"><a href="Lost_comet" title="Lost comet">Lost</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;text-align: center;">Recovered</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="9P/Tempel" class="mw-redirect" title="9P/Tempel">9P/Tempel</a></li>