Leonids
{{Short description|Meteor shower associated with the comet Tempel–Tuttle}}
{{Other uses|Leonid (disambiguation)}}
{{Use dmy dates|date=October 2020}}
{{Infobox meteor shower
| name = Leonids
| image = 245px
| caption = A Leonid meteor during the peak of the Leonids in 2009
| pronounce = {{IPAc-en|ˈ|l|iː|ən|ɪ|d|z}}
| date = 902 AD (first record)
| parent = 55P/Tempel–Tuttle
| constellation = Leo
| month = {{nowrap|3 November – 2 December}}
| peak = 17 November
| notes =
}}
The Leonids ({{IPAc-en|ˈ|l|iː|ən|ɪ|d|z}} {{respell|LEE|ə-nidz}}) are a prolific annual meteor shower associated with the comet Tempel–Tuttle, and are also known for their spectacular meteor storms that occur about every 33 years.{{cite web |last=Byrd |first=Deborah |title=All you need to know: 2019's Leonid meteor shower |url=https://earthsky.org/?p=29831 |url-status=live |publisher=EarthSky |date=15 November 2018 |access-date=26 February 2019 |archive-url=https://web.archive.org/web/20191111225720/https://earthsky.org/?p=29831 |archive-date=11 November 2019}} The Leonids get their name from the location of their radiant in the constellation Leo: the meteors appear to radiate from that point in the sky. The name is derived from Greek and Latin with the prefix Leo- referring to the constellation and the suffix -ids signifying that the meteor shower is the offspring of, descendent of, the constellation Leo. {{cite web|url=https://www.dictionary.com/browse/id#american-id-2-definitions|title=Id|author=dictionary.com|publisher=dictionary.com|date=12 February 2025|access-date=12 February 2025|archive-date=7 February 2025|archive-url= https://web.archive.org/web/20250207000614/https://www.dictionary.com/browse/id#american-id-2-definitions|url-status=live}}
Earth moves through meteoroid streams left from passages of a comet. The streams consist of solid particles, known as meteoroids, normally ejected by the comet as its frozen gases evaporate under the heat of the Sun once within Jupiter's orbit. Due to the retrograde orbit of 55P/Tempel–Tuttle, the Leonids are fast moving streams which encounter the path of Earth and impact at {{cvt|70|km/s}}. It is the fastest annual meteor shower. Larger Leonids which are about {{cvt|10|mm|sigfig=1}} across have a mass of {{cvt|0.5|g|oz|sigfig=1}} and are known for generating bright (apparent magnitude −1.5) meteors. An annual Leonid shower may deposit 12 or 13 tons of particles across the entire planet.
The meteoroids left by the comet are organized in trails in orbits similar to{{snd}}though different from{{snd}}that of the comet. They are differentially disturbed by the planets, in particular Jupiter,{{cite journal |last1=McNaught |first1=Robert H. |author1-link=Robert H. McNaught | last2 = Asher | first2 = David J. | author2-link = David J. Asher | title = Leonid Dust Trails and Meteor Storms | journal = WGN, Journal of the International Meteor Organization | volume = 27 | issue = 2 | pages = 85–102 | date = 1999 |bibcode = 1999JIMO...27...85M}} and to a lesser extent by radiation pressure from the Sun{{snd}}the Poynting–Robertson effect and the Yarkovsky effect.{{cite thesis |last=Brown |first=Peter Gordon |title=Evolution of Two periodic Meteoroid Streams: the Perseids and Leonids |url=http://aquarid.physics.uwo.ca/~pbrown/thesis.html |url-status=live |year=1999 |page=4005 |access-date=24 December 2009 |bibcode=1999PhDT.........7B |archive-url=https://web.archive.org/web/20100605010213/http://aquarid.physics.uwo.ca/~pbrown/thesis.html |archive-date=5 June 2010}} These trails of meteoroids cause meteor showers when Earth encounters them. Old trails are spatially not dense and compose the meteor shower with a few meteors per minute. In the case of the Leonids, that tends to peak around 18 November, but some are spread through several days on either side and the specific peak changes every year. Conversely, young trails are spatially very dense and the cause of meteor outbursts when the Earth enters one.
The Leonids also produce {{em|meteor storms}} (very large outbursts) about every 33 years, during which activity exceeds 1,000 meteors per hour,{{cite web|url=https://www.cbsnews.com/news/leonids-meteor-shower-2019-will-light-up-the-sky-heres-how-to-watch/|title=Leonids meteor shower will soon light up the sky. Here's how to watch.|author=Sophie Lewis|publisher=CBS News|date=16 November 2019|access-date=18 August 2020|archive-date=31 October 2020|archive-url=https://web.archive.org/web/20201031231913/https://www.cbsnews.com/news/leonids-meteor-shower-2019-will-light-up-the-sky-heres-how-to-watch/|url-status=live}} with some events exceeding 100,000 meteors per hour,{{cite news|url=https://www.washingtonpost.com/weather/2019/11/18/leonid-shower-dud-past-years-have-featured-extreme-meteor-storms/|title=Leonid shower a dud in 2019, but past years have featured extreme 'meteor storms'|author=Matthew Cappucci|newspaper=The Washington Post|date=18 November 2019|access-date=18 August 2020|archive-date=26 September 2020|archive-url=https://web.archive.org/web/20200926175816/https://www.washingtonpost.com/weather/2019/11/18/leonid-shower-dud-past-years-have-featured-extreme-meteor-storms/|url-status=live}} in contrast to the sporadic background (5 to 8 meteors per hour) and the shower background (several meteors per hour).
| class="wikitable" style="font-size: 0.9em"
! Size ! Comparable in brightness | ||
| {{convert|2|mm|sigfig=1|abbr=on}} | +3.7 (visual) | Delta Ursae Majoris |
| {{convert|10|mm|sigfig=1|abbr=on}} | −1.5 (bright) | Sirius |
| {{convert|20|mm|sigfig=1|abbr=on}} | −3.8 (Fireball) | Venus |
History
=1800s=
{{multiple image
| total_width = 400
| image1 = Leonids-1833.jpg
| width1 = 499
| height1 = 764
| alt1 = A sky full of shooting stars over a village
| caption1 = A famous depiction of the 1833 meteor storm, produced in 1889 for the Seventh-day Adventist book Bible Readings for the Home Circle.
| image2 = Leonids-Pickering.jpg
| width2 = 220
| height2 = 253
| alt2 = A sky full of shooting stars over the Niagara falls
| caption2 = Woodcut print depicts the shower as seen at Niagara Falls, New York. Mechanics' Magazine said this illustration was made by an editor named Pickering "who witnessed the scene."
}}
The Leonids are famous because their meteor showers, or storms, can be among the most spectacular. Because of the storm of 1833 and the developments in scientific thought of the time (see for example the identification of Halley's Comet), the Leonids have had a major effect on the scientific study of meteors, which had previously been thought to be atmospheric phenomena. Although it has been suggested the Leonid meteor shower and storms have been noted in ancient times,{{cite journal
|author=Mohammed Omar Suleyman
| title =The Leonid meteor shower and the history of the Semites (Arabs and Jews)
| journal =Journal of the International Meteor Organization
| volume =37
| issue =3
| pages =84–91
| date =2009
| bibcode =2009JIMO...37...84S
}} it was the meteor storm of November 12–13, 1833 that broke into people's modern-day awareness. One estimate of the peak rate is over one hundred thousand meteors an hour,{{cite web|url=https://www.space.com/9517-leonid-meteor-shower-revealed-shooting-star-show-brilliant-history.html|title=The Leonid Meteor Shower Revealed: Shooting Star Show's Brilliant History|author=Joe Rao|publisher=Space.com|date=12 November 2010|access-date=18 August 2020|archive-date=9 August 2020|archive-url=https://web.archive.org/web/20200809221932/https://www.space.com/9517-leonid-meteor-shower-revealed-shooting-star-show-brilliant-history.html|url-status=live}} while another, done as the storm abated, estimated in excess of 240,000 meteors during the nine hours of the storm,{{cite web|url=http://leonid.arc.nasa.gov/history.html|title=Leonid MAC - Brief history of the Leonid shower|publisher=NASA|date=2004|access-date=18 August 2020|archive-date=22 May 2012|archive-url=https://web.archive.org/web/20120522025820/http://leonid.arc.nasa.gov/history.html|url-status=live}} over the entire region of North America east of the Rocky Mountains.
The event was marked by several nations of Native Americans: the Cheyenne established a peace treaty{{cite web
| url = http://www.aaanativearts.com/mailbag-archive/1373-what-is-the-underlying-significance-of-the-birth-of-the-white-buffalo.html
| title = What is the underlying significance of the birth of the white buffalo?
| publisher = AAA Native Arts
| access-date = 20 July 2012
| date = 2007-02-24
| archive-date = 21 March 2015
| archive-url = https://web.archive.org/web/20150321044648/http://www.aaanativearts.com/mailbag-archive/1373-what-is-the-underlying-significance-of-the-birth-of-the-white-buffalo.html
| url-status = dead
}} and the Lakota calendar was reset.{{cite web | title = Counting by Winters | work = Lakota Winter Counts Online Exhibit by the Smithsonian Institution National Museum of Natural History | publisher = Smithsonian Institution | url = http://wintercounts.si.edu/html_version/html/index.html | access-date = 2009-12-24 | archive-url = https://web.archive.org/web/20140423231754/http://wintercounts.si.edu/html_version/html/index.html | archive-date = 2014-04-23 | url-status = dead }}{{cite book | title = The Year the Stars Fell | editor-last = Greene | editor-first = Candace S. | editor2-last = Thornton | editor2-first = Russell | url = https://archive.org/details/yearstarsfelllak0000unse | isbn = 978-0-8032-2211-3 | date = June 2007 | publisher = U of Nebraska Press | url-access = registration }} Many Native American birthdays were calculated by reference to the 1833 Leonid event.{{cite book|last=Zapffe|first=Carl A.|title=Kahbe nagwi wens: The man who lived in 3 centuries|location=Brainerd, MN|publisher=Historic Heartland Association|year=1975|page=1|isbn=978-0-910623-00-1}} in {{cite book |first=Timothy G. |last=Roufs |title=When Everybody Called Me Gah-bay-bi-nayss, "Forever-Flying-Bird": An Ethnographic Biography of Paul Peter Buffalo |url=http://www.d.umn.edu/cla/faculty/troufs/Buffalo/PB41.html |year=2008 |publisher=University of Minnesota Duluth}} footnote 35 Abolitionists including Harriet Tubman and Frederick Douglass as well as slave-owners took note{{cite web| title = The Night the Stars Fell; My Search for Amanda Young| work = Freedmen of the Frontier – African American Historical and Genealogical Resource Page of the city of Ft. Smith Arkansas| url = https://www.angelfire.com/ar/freedmen/stars.html| access-date = 2009-12-24| archive-date = 30 November 2020| archive-url = https://web.archive.org/web/20201130045838/https://www.angelfire.com/ar/freedmen/stars.html| url-status = live}}{{cite news | last = Bell | first = Madison Smartt | title = The Fugitive | newspaper = New York Times | date = 24 June 2007 | url = https://www.nytimes.com/2007/06/24/books/review/Bell.html?_r=2&ref=books&oref=slogin | access-date = 2009-12-24 | archive-date = 2 September 2018 | archive-url = https://web.archive.org/web/20180902052340/https://www.nytimes.com/2007/06/24/books/review/Bell.html?_r=2&ref=books&oref=slogin | url-status = live }} and others.{{cite news | title = The Great Leonid Meteor Storm of 1833 – A first-hand account by Elder Samuel Rogers | newspaper = NASA Science News | date = 22 June 1999 | url = https://science.nasa.gov/newhome/headlines/ast22jun99%5F2.htm | access-date = 2009-12-24 | archive-url = https://web.archive.org/web/20091218223803/http://science.nasa.gov/newhome/headlines/ast22jun99_2.htm | archive-date = 18 December 2009 | url-status = dead }} The New York Evening Post carried a series of articles on the event including reports from Canada to Jamaica,* {{cite news
| title =Wednesday, November 13
| newspaper =The Evening Post
| location =New York, New York
| page =2
| date =13 Nov 1833
| url =https://www.newspapers.com/clip/179386/1833_leonids/
| access-date =27 Oct 2015
| archive-date =13 May 2022
| archive-url =https://web.archive.org/web/20220513141115/https://www.newspapers.com/clip/179386/1833-leonids/
| url-status =live
}}
- {{cite news
| title =Thursday, November 14
| newspaper =The Evening Post
| location =New York, New York
| page =2
| date =14 Nov 1833
| url =https://www.newspapers.com/clip/179392/1833_leonids/
| access-date =27 Oct 2015
| archive-date =4 March 2016
| archive-url =https://web.archive.org/web/20160304211411/https://www.newspapers.com/clip/179392/1833_leonids/
| url-status =live
}}
- {{cite news
| title =Friday, November 15
| newspaper =The Evening Post
| location =New York, New York
| page =2
| date =15 Nov 1833
| url =https://www.newspapers.com/clip/179401/1833_leonids/
| access-date =27 Oct 2015
| archive-date =13 May 2022
| archive-url =https://web.archive.org/web/20220513141108/https://www.newspapers.com/clip/179401/1833-leonids/
| url-status =live
}}
- {{cite news
| title =The late celestial phenomena…
| newspaper =The Evening Post
| location =New York, New York
| page =2
| date =22 Nov 1833
| url =https://www.newspapers.com/clip/179424/1833_leonids/
| access-date =27 Oct 2015
| archive-date =4 March 2016
| archive-url =https://web.archive.org/web/20160304100403/https://www.newspapers.com/clip/179424/1833_leonids/
| url-status =live
}}
- {{cite news
| title =An extract of a letter…
| newspaper =The Evening Post
| location =New York, New York
| page =2
| date =23 Nov 1833
| url =https://www.newspapers.com/clip/179427/1833_leonids/
| access-date =27 Oct 2015
| archive-date =13 May 2022
| archive-url =https://web.archive.org/web/20220513141137/https://www.newspapers.com/clip/179427/1833-leonids/
| url-status =live
}}
- {{cite news
| title =New Orleans, Nov 14…
| newspaper =The Evening Post
| location =New York, New York
| page =2
| date =28 Nov 1833
| url =https://www.newspapers.com/clip/179449/1833_leonids/
| access-date =27 Oct 2015
| archive-date =13 May 2022
| archive-url =https://web.archive.org/web/20220513141108/https://www.newspapers.com/clip/179449/1833-leonids/
| url-status =live
}}
- {{cite news
| title =A Halifax article…
| newspaper =The Evening Post
| location =New York, New York
| page =2
| date =29 Nov 1833
| url =https://www.newspapers.com/clip/179451/1833_leonids/
| access-date =27 Oct 2015
| archive-date =4 March 2016
| archive-url =https://web.archive.org/web/20160304141904/https://www.newspapers.com/clip/179451/1833_leonids/
| url-status =live
}}
- {{cite news
| title =From Jamaica…
| newspaper =The Evening Post
| location =(New York, New York
| page =2
| date =27 Dec 1833
| url =https://www.newspapers.com/clip/179474/1833_leonids/
| access-date =27 Oct 2015
| archive-date =4 March 2016
| archive-url =https://web.archive.org/web/20160304092116/https://www.newspapers.com/clip/179474/1833_leonids/
| url-status =live
}} it made news in several states beyond New York* {{cite news
| title =Meteoric Phenomenon
| newspaper =The Adams Sentinel
| location =Gettysburg, Pennsylvania
| page =3
| date =18 Nov 1833
| url =https://www.newspapers.com/clip/179408/1833_leonids/
| access-date =27 Oct 2015
| archive-date =4 March 2016
| archive-url =https://web.archive.org/web/20160304131358/https://www.newspapers.com/clip/179408/1833_leonids/
| url-status =live
}}
- {{cite news
| title =Remarkable Phenomenon
| newspaper =Huron Reflector
| location =Norwalk, Ohio
| page =2
| date =19 Nov 1833
| url =https://www.newspapers.com/clip/179416/1833_leonids/
| access-date =27 Oct 2015
| archive-date =6 March 2016
| archive-url =https://web.archive.org/web/20160306161103/https://www.newspapers.com/clip/179416/1833_leonids/
| url-status =live
}}
- {{cite news
| title =Falling stars
| newspaper =Newbern Sentinel
| location =New Bern, North Carolina
| page =2
| date =6 Dec 1833
| url =https://www.newspapers.com/clip/179463/1833_leonids/
| access-date =27 Oct 2015
| archive-date =4 March 2016
| archive-url =https://web.archive.org/web/20160304093110/https://www.newspapers.com/clip/179463/1833_leonids/
| url-status =live
| author=Mary L. Kwas
| title =The Spectacular 1833 Leonid Meteor Storm: The View from Arkansas
| journal =The Arkansas Historical Quarterly
| volume =58
| issue =3
| pages =314–324
| date = 1999
| jstor =40026232
| doi=10.2307/40026232}} and, though it appeared in North America, was talked about in Europe.{{cite news
| title =At Halifax, Nova Scotia…
| newspaper =The Times
| location =London, England
| page =5
| date =11 Dec 1833
| url =https://www.newspapers.com/clip/179466/1833_leonids/
| access-date =27 Oct 2015
| archive-date =4 March 2016
| archive-url =https://web.archive.org/web/20160304102234/https://www.newspapers.com/clip/179466/1833_leonids/
| url-status =live
}} The journalism of the event tended to rise above the partisan debates of the time and reviewed facts as they could be sought out.{{cite journal
|author=Mark Littmann
| title =American Newspapers and the Great Meteor Storm of 1833: A Case Study in Science Journalism
| journal =Journalism and Communication Monographs
| volume =10
| issue =3
| pages =249–284
| date =September 2008
| doi =10.1177/152263790801000302
| s2cid =144266410
}} Abraham Lincoln commented on it years later.{{cite journal
|author1 = Donald W. Olson
|author2 = Laurie E. Jasinski
|title = Abe Lincoln and the Leonids
|journal = Sky and Telescope
|pages = 34–5
|date = Nov 1999
|volume = 98
|issue = 5
|bibcode = 1999S&T....98e..34O
|url = http://media.skyandtelescope.com/documents/LincolnandLeonids.pdf
|access-date = 27 Oct 2015
|archive-url = https://web.archive.org/web/20160304090034/http://media.skyandtelescope.com/documents/LincolnandLeonids.pdf
|archive-date = 4 March 2016
|url-status = dead
}} Near Independence, Missouri, in Clay County, a refugee Mormon community watched the meteor shower on the banks of the Missouri River after having been driven from their homes by local settlers.{{cite book|title=The autobiography of Parley Parker Pratt, one of the twelve apostles of the Church of Jesus Christ of Latter-day Saints: embracing his life, ministry and travels, with extracts, in prose and verse, from his miscellaneous writings|url=https://archive.org/stream/autobiographyofp00prat#page/n3/mode/2up|via=archive.org|publisher=Chicago : Pub. for Pratt bros. by Law, King & Law|year=1888}} Joseph Smith, the founder and first leader of Mormonism, afterwards noted in his journal for November 1833 his belief that this event was "a litteral [sic] fulfillment of the word of God" and a harbinger of the imminent second coming of Christ.[http://josephsmithpapers.org/paperSummary/journal-1832-1834#!/paperSummary/journal-1832-1834&p=20 The Joseph Smith Papers] {{webarchive |url=https://web.archive.org/web/20140608171258/http://josephsmithpapers.org/paperSummary/journal-1832-1834#!/paperSummary/journal-1832-1834&p=20 |date=8 June 2014}} Journals Volume 1: 1832–1839 Though it was noted in the midwest and eastern areas, it was also noted in Far West, Missouri.{{cite journal
|author = Erwin F. Lange
|title = Fireballs, meteorites, and meteor showers
|journal = The Ore Bin
|volume = 30
|issue = 8
|pages = 145–150
|publisher = Oregon. Dept. of Geology and Mineral Industries
|date = August 1968
|url = http://ir.library.oregonstate.edu/xmlui/handle/1957/3294
|access-date = 27 Oct 2015
|archive-date = 4 March 2016
|archive-url = https://web.archive.org/web/20160304113138/http://ir.library.oregonstate.edu/xmlui/handle/1957/3294
|url-status = live
}}
Denison Olmsted explained the event most accurately. After spending the last weeks of 1833 collecting information, he presented his findings in January 1834 to the American Journal of Science and Arts, published in January–April 1834,{{cite journal|last=Olmsted|first=Denison|title=Observations on the Meteors of November 13th, 1833|journal=The American Journal of Science and Arts|date=1833|volume=25|pages=363–411|url=https://www.biodiversitylibrary.org/page/30964366|access-date=3 April 2012|archive-date=24 September 2015|archive-url=https://web.archive.org/web/20150924195349/http://www.biodiversitylibrary.org/page/30964366|url-status=live}} and January 1836.{{cite journal|last=Olmsted|first=Denison|title=Facts respecting the Meteoric Phenomena of November 13th, 1834.|journal=The American Journal of Science and Arts|date=1836|volume=29|issue=1|pages=168–170|url=https://www.biodiversitylibrary.org/page/31127293|access-date=13 January 2018|archive-date=19 July 2017|archive-url=https://web.archive.org/web/20170719130824/http://www.biodiversitylibrary.org/page/31127293|url-status=live}} He noted the shower was of short duration and was not seen in Europe, and that the meteors radiated from a point in the constellation of Leo and he speculated the meteors had originated from a cloud of particles in space.[http://meteorshowersonline.com/leonids.html Observing the Leonids] {{Webarchive|url=https://web.archive.org/web/20130304005613/http://meteorshowersonline.com/leonids.html |date=2013-03-04 }} Gary W. Kronk Accounts of the 1866 repeat of the Leonids counted hundreds per minute/a few thousand per hour in Europe.[http://www.peyman.info/cl/Baha'i/Others/ROB/V2/p422-426Apndx_I.html The Revelation of Bahá'u'lláh, Vol 2] {{Webarchive|url=https://web.archive.org/web/20170508204456/http://www.peyman.info/cl/Baha%27i/Others/ROB/V2/p422-426Apndx_I.html |date=8 May 2017 }} by Adib Taherzadeh, Appendix I: The Star-fall of 1866 The Leonids were again seen in 1867, when moonlight reduced the rates to 1,000 meteors per hour. Another strong appearance of the Leonids in 1868 reached an intensity of 1,000 meteors per hour in dark skies. It was in 1866–67 that information on Comet Tempel-Tuttle was gathered, pointing it out as the source of the meteor shower and meteor storms. When the storms failed to return in 1899, it was generally thought that the dust had moved on and the storms were a thing of the past.
=1900s=
In 1966, a spectacular meteor storm was seen over the Americas.{{cite web | title = Eyewitness accounts of the 1966 Leonid Storm | publisher = P. Jenniskens/NASA-ARC | url = http://leonid.arc.nasa.gov/1966.html | access-date = 2009-12-25 | archive-date = 31 October 2018 | archive-url = https://web.archive.org/web/20181031013914/https://leonid.arc.nasa.gov/1966.html | url-status = live }} Historical notes were gathered thus noting the Leonids back to 900 AD.{{citation | last1 = McIntosh | first1 = Bruce. A | last2 = Millman | first2 = Peter. M. | title = The Leonids by Radar--1957 to 1968 | journal = Meteoritics | volume = 5 | issue = 1 | pages = 1–18 | date = 1970 | doi =10.1111/j.1945-5100.1970.tb00385.x|bibcode = 1970Metic...5....1M | doi-access = free }} Radar studies showed the 1966 storm included a relatively high percentage of smaller particles while 1965's lower activity had a much higher proportion of larger particles. In 1981 Donald K. Yeomans of the Jet Propulsion Laboratory reviewed the history of meteor showers for the Leonids and the history of the dynamic orbit of Comet Tempel-Tuttle.{{citation | last = Yeomans | first = Donald K. | title = Comet Tempel-Tuttle and the Leonid meteors | journal = Icarus | volume = 47 | issue = 3 | pages = 492–499 | date = September 1981 | doi = 10.1016/0019-1035(81)90198-6 | bibcode=1981Icar...47..492Y}} A graph{{cite web | archive-url=https://web.archive.org/web/20061123062359/http://www.iltrails.org/leokin4.gif |archive-date=23 November 2006 | url=http://www.iltrails.org/leokin4.gif | title=leokin4.gif | publisher=iltrails.org | via=archive.org | access-date=6 March 2021 }} from it was adapted and re-published in Sky and Telescope.[http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/19339/1/98-0663.pdf Comet 55P/Tempel-Tuttle and the Leonid Meteors] {{webarchive|url=https://web.archive.org/web/20070630230010/http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/19339/1/98-0663.pdf |date=2007-06-30 }}(1996, see p. 6) It showed relative positions of the Earth and Tempel-Tuttle and marks where Earth encountered dense dust. This showed that the meteoroids are mostly behind and outside the path of the comet, but paths of the Earth through the cloud of particles resulting in powerful storms were very near paths of nearly no activity. But overall the 1998 Leonids were in a favorable position so interest was rising.
Leading up to the 1998 return, an airborne observing campaign was organized to mobilize modern observing techniques by Peter Jenniskens at NASA Ames Research Center. In 1999, there were also efforts to observe impacts of meteoroids on the Moon, as an example of transient lunar phenomenon. A particular reason to observe the Moon is that our vantage from a location on Earth sees only meteors coming into the atmosphere relatively close to us, while impacts on the Moon would be visible from across the Moon in a single view.[https://science.nasa.gov/newhome/headlines/ast22nov99_1.htm A Leonid on the Moon?] {{webarchive |url=https://web.archive.org/web/20090827140552/http://science.nasa.gov/newhome/headlines/ast22nov99_1.htm |date=2009-08-27}} by Dr. Tony Phillips The sodium tail of the Moon tripled just after the 1998 Leonid shower which was composed of larger meteoroids (which in the case of the Earth was witnessed as fireballs).{{cite web | last = McNaught | first = Robert H. | author-link = Robert H. McNaught | title = Lunar Leonids: Encounters of the Moon with Leonid dust trails | publisher = spaceweather.com | date = 2000-10-27 | url = http://www.spaceweather.com/meteoroutlook/lunarleonids.html | access-date = 2009-12-25 | archive-date = 3 March 2016 | archive-url = https://web.archive.org/web/20160303230153/http://www.spaceweather.com/meteoroutlook/lunarleonids.html | url-status = live}} However, in 1999 the sodium tail of the Moon did not change from the Leonid impacts.
Research by Kondrat'eva, Reznikov and colleagues{{citation | last1 = Kondrat'eva | first1 = E.D. | last2 = Reznikov | first2 = E.A. | title = Comet Tempel-Tuttle and the Leonid meteor swarm | journal = Solar System Research | volume = 19 | pages = 96–101 | date = 1985 | bibcode=1985AVest..19..144K}} at Kazan University had shown how meteor storms could be accurately predicted, but for some years the worldwide meteor community remained largely unaware of these results. The work of David J. Asher, Armagh Observatory and Robert H. McNaught, Siding Spring Observatory and independently by Esko Lyytinen{{citation | last = Lyytinen | first = Esko | journal = Meta Research Bulletin | volume = 8 | pages = 33–40 | date = 1999 | url = http://metaresearch.org/publications/bulletin/#VOL8 | title = #3 Leonid Predictions for the years 1999–2007 with the Satellite Model of Comets | access-date = 2010-01-10 | archive-url = https://web.archive.org/web/20110727081844/http://metaresearch.org/publications/bulletin/#VOL8 | archive-date = 2011-07-27 | url-status = dead}}{{citation | last1 = Lyytinen | first1 = Esko J. | last2 = Flandern | first2 = Tom Van | title = Predicting the Strength of Leonid Outbursts | journal = Earth, Moon, and Planets | volume = 82–83 | pages = 149–166 | date = January 2000 | issn = 1573-0794| doi = 10.1023/A:1017068618114| s2cid = 20890989}}, in 1999, following on from the Kazan research, is considered by most meteor experts as the breakthrough in modern analysis of meteor storms. Whereas previously it was hazardous to guess if there would be a storm or little activity, the predictions of Asher and McNaught timed bursts in activity down to ten minutes by narrowing down the clouds of particles to individual streams from each passage of the comet, and their trajectories amended by subsequent passage near planets. However, whether a specific meteoroid trail will be primarily composed of small or large particles, and thus the relative brightness of the meteors, was not understood. But McNaught did extend the work to examine the placement of the Moon with trails and saw a large chance of a storm impacting in 1999 from a trail while there were less direct impacts from trails in 2000 and 2001 (successive contact with trails through 2006 showed no hits).
File:Leonid meteor shower as seen from space (1997).jpg NASA satellite in 1997]]
=2000s=
Viewing campaigns resulted in spectacular footage from the 1999, 2001, and 2002 storms which produced up to 3,000 Leonid meteors per hour. Predictions for the Moon's Leonid impacts also noted that in 2000 the side of the Moon facing the stream was away from the Earth, but that impacts should be in number enough to raise a cloud of particles kicked off the Moon which could cause a detectable increase in the sodium tail of the Moon. Research using the explanation of meteor trails/streams have explained the storms of the past. The 1833 storm was not due to the recent passage of the comet, but from a direct impact with the previous 1800 dust trail.[http://www.arm.ac.uk/leonid/dust1833.html Armagh Observatory] {{webarchive |url=https://web.archive.org/web/20061206225925/http://www.arm.ac.uk/leonid/dust1833.html |date=6 December 2006}} Leonid dust trail positions in 1833. The meteoroids from the 1733 passage of Comet Tempel-Tuttle resulted in the 1866 storm[http://www.arm.ac.uk/leonid/dust1866.html Leonid dust trail positions in 1866] {{Webarchive|url=https://web.archive.org/web/20091123225350/http://www.arm.ac.uk/leonid/dust1866.html |date=23 November 2009 }} Armagh Observatory and the 1966 storm was from the 1899 passage of the comet.[http://www.arm.ac.uk/leonid/dust1966.html Armagh Observatory] {{Webarchive|url=https://web.archive.org/web/20061009023201/http://www.arm.ac.uk/leonid/dust1966.html |date=9 October 2006 }} Leonid dust trail positions in 1966 The double spikes in Leonid activity in 2001 and in 2002 were due to the passage of the comet's dust ejected in 1767 and 1866.[http://www.meteorobs.org/lunar.html Meteor Orbs.org] {{webarchive|url=https://web.archive.org/web/20060928082108/http://www.meteorobs.org/lunar.html |date=2006-09-28 }} Predictions & Observations of Lunar Meteor impacts This ground breaking work was soon applied to other meteor showers – for example the 2004 June Bootids. Peter Jenniskens has published predictions for the next 50 years.{{cite book |last=Jenniskens |first=P. |title=Meteor Showers and their Parent Comets |publisher=Cambridge University Press |location=Cambridge, UK |date=2006 |isbn=978-0-521-85349-1 }} However, a close encounter with Jupiter is expected to perturb the comet's path, and many streams, making storms of historic magnitude unlikely for many decades. Recent work tries to take into account the roles of differences in parent bodies and the specifics of their orbits, ejection velocities off the solid mass of the core of a comet, radiation pressure from the Sun, the Poynting–Robertson effect, and the Yarkovsky effect on the particles of different sizes and rates of rotation to explain differences between meteor showers in terms of being predominantly fireballs or small meteors.
| style="margin:auto;" | class="wikitable"
! width="10%" | Year ! width="15%" | Leonids active between ! width="65%" | Peak of shower ! width="10%" | ZHRmax |
| align="center"|2006
| align="center"| | 19 Nov. Outburst of ZHR=35–40 was predicted from the 1932 trail. |
| align="center"|2007
| align="center"| | 19 Nov. Outburst of ZHR=~30 from the 1932 trail was predicted for 18 Nov. |
| align="center"|2008
| align="center"|14–22 November | 17 Nov.{{Cite web | title = Return of the Leonids | publisher = NASA | date = 4 Dec 2008 | url = https://science.nasa.gov/headlines/y2008/04dec_leonids2009.htm | access-date = 2009-10-21 | archive-url = https://web.archive.org/web/20091020190449/http://science.nasa.gov/headlines/y2008/04dec_leonids2009.htm | archive-date = 20 October 2009 | url-status = dead }} Considerable outburst of ZHR=130 from the 1466 trail was predicted for 17 Nov. |
| align="center"|2009
| align="center"|10–21 November | ZHRmax ranging from 100{{Cite web | url=http://news.nationalgeographic.com/news/2009/11/091116-leonids-meteor-shower-best-2009.html | title=Leonid Meteor Shower: Best Sky Show Tonight | author=Fazekas, Andrew | publisher=National Geographic News | date=16 November 2009 | access-date=16 November 2009 | archive-date=19 January 2017 | archive-url=https://web.archive.org/web/20170119191351/http://news.nationalgeographic.com/news/2009/11/091116-leonids-meteor-shower-best-2009.html | url-status=dead | title = IMO Meteor Shower Calendar 2009 | publisher = The International Meteor Organization | date = 1997–2009 | url = http://www.imo.net/calendar/2009#leo | access-date = 2009-10-21 | archive-date = 9 February 2010 | archive-url = https://web.archive.org/web/20100209060215/http://www.imo.net/calendar/2009#leo | url-status = live }} to over 500{{cite news | title = Strong Leonid Meteor Shower Predicted for 2009 | work = Space.com | date = 4 December 2008 | url = http://www.space.com/scienceastronomy/081204-leonids-meteor-shower-2009.html | access-date = 2009-10-22 | archive-date = 17 August 2010 | archive-url = https://web.archive.org/web/20100817154258/http://www.space.com/scienceastronomy/081204-leonids-meteor-shower-2009.html | url-status = live |last = Lopez |first = Mike |title = Watch Out for Leonids 2009 Meteor Shower |date = 7 December 2008 |url = http://science.mikelopez.info/2008/12/07/watch-out-for-leonids-2009-meteor-shower/ |access-date = 2009-10-22 |url-status = dead |archive-url = https://web.archive.org/web/20090819115301/http://science.mikelopez.info/2008/12/07/watch-out-for-leonids-2009-meteor-shower/ |archive-date = 19 August 2009 }} on 17 Nov. The peak was observed at predicted time.{{Cite web | url=http://www.imo.net/live/leonids2009 | title=Leonids 2009: visual data quicklook | publisher=The International Meteor Organization | url-status=dead | archive-url=https://web.archive.org/web/20100119054421/http://www.imo.net/live/leonids2009/ | archive-date=2010-01-19 }} |
| align="center"|2010
| align="center"|10–23 November | 18 Nov | align="center"|32±4{{cite news |last1=Dickinson |first1=David |title=From a Roar to a Purr: Prospects for the 2015 November Leonid Meteors |url=https://www.universetoday.com/123251/from-a-roar-to-a-purr-prospects-for-the-2015-november-leonid-meteors/ |agency=Universe Today |access-date=1 October 2021 |archive-date=1 October 2021 |archive-url=https://web.archive.org/web/20211001211235/https://www.universetoday.com/123251/from-a-roar-to-a-purr-prospects-for-the-2015-november-leonid-meteors/ |url-status=live }}{{Cite web|url=http://www.imo.net/live/leonids2010/|archiveurl=https://web.archive.org/web/20121127105159/http://imo.net/live/leonids2010/|url-status=dead|title=Leonids 2010: visual data quicklook|archive-date=27 November 2012|access-date=14 December 2021}} |
| align="center"|2011
| align="center"|6–30 November | 18 Nov | align="center"|22±3{{Cite web|url=http://www.imo.net/live/leonids2011/|archiveurl=https://web.archive.org/web/20121031161949/http://imo.net/live/leonids2011/|url-status=dead|title=Leonids 2011: visual data quicklook|archive-date=31 October 2012|access-date=14 December 2021}} |
| align="center"|2012
| align="center"|6–30 November | 20 Nov. Nov 17 ZHR=5–10 (predicted) / 20 Nov ZHR=10–15 (predicted from 1400 trail) | align="center"|47±11{{Cite web|url=http://www.imo.net/live/leonids2012/|archiveurl=https://web.archive.org/web/20121219015552/http://imo.net/live/leonids2012/|url-status=dead|title=Leonids 2012: visual data quicklook|archive-date=19 December 2012|access-date=14 December 2021}} |
| align="center"|2013
| align="center"|15–20 November | 17 Nov but was washed out by a Full moon on 17 Nov | align="center"|– |
| align="center"|2014
| align="center"|6–30 November | 18 Nov | align="center"|15±4{{Cite news|last=Anderson|first=Janet|date=14 November 2014|title=Brilliant Leonids Meteor Shower Peak Occurs Morning of Nov. 18|url=https://www.nasa.gov/watchtheskies/leonid-meteor-shower-nov2014.html|agency=NASA|access-date=1 October 2021|archive-date=7 April 2022|archive-url=https://web.archive.org/web/20220407112259/https://www.nasa.gov/watchtheskies/leonid-meteor-shower-nov2014.html|url-status=live}} |
| align="center"|2015
| align="center"|6–30 November |
| align="center"|2016
| align="center"|6–30 November |
| align="center"|2017
| align="center"|6–30 November |
| align="center"|2018
| align="center"|6–30 November |
| align="center"|2019
| align="center"|6–30 November | 17 Nov |
| align="center"|2020
| align="center"|6–30 November | 17 Nov |
| align="center"|2021
| align="center"|6–30 November |
| align="center"|2022
| align="center"|17-21 November | 17 Nov (there was a low possibility of an outburst from the 1733 meteoroid stream on 19 November) | align="center"|15 (predicted) - 300 (unlikely){{cite web|last1=Mikhail|first1=Maslov|title=Leonids 2021-2030|url=http://feraj.ru/Radiants/Predictions/1901-2100eng/Leo2021-2030eng.html|url-status=live|access-date=10 June 2021|archive-date=10 June 2021|archive-url=https://web.archive.org/web/20210610102748/http://feraj.ru/Radiants/Predictions/1901-2100eng/Leo2021-2030eng.html}} |
| align="center"|2023
| align="center"|3 Nov - 2 Dec | 17 Nov (a modest increase is possible from the 1767 meteoroid stream on 21 November) |
| align="center"|2024
| align="center"| | 17 Nov |
| align="center"|2025
| align="center"| | 17 Nov (any outburst is likely to be from the 1699 meteoroid stream) |
| align="center"|2026
| align="center"| | 17 Nov |
| align="center"|2027
| align="center"| | 17 Nov (possible activity from 1167 meteoroid stream on 20 November) |
| align="center"|2028
| align="center"| | 17 Nov |
| align="center"|2029
| align="center"| | 17 Nov (possible activity from 1998 meteoroid stream) |
| align="center"|2030
| align="center"| | 17 Nov |
| align="center"|2031
| align="center"| | 17 Nov |
| align="center"|2032
| align="center"| | 17 Nov |
| align="center"|2033
| align="center"| | 17 Nov (Outburst likely from 1899 meteoroid stream. Encountering a younger stream typically generates more activity.) |
| align="center"|2034
| align="center"| | 17–18 Nov (probable outburst from the young 1932 meteoroid stream on 18 November) |
| align="center"|2061
| align="center"| | (Possible outburst from the young 1998 meteoroid stream on 19 November) |
| align="center"|2099
| align="center"| | (Possible outburst from dense stream){{cite web |title=Meteor Shower Calendar 2022-2023 |publisher=American Meteor Society (AMS) |url=https://www.amsmeteors.org/meteor-showers/meteor-shower-calendar/#Leonids |accessdate=2023-09-09}} | align="center"|1000+? |
Predictions until the end of the 21st century have been published by Mikhail Maslov.{{Citation | last = Maslov | first = Mikhail | title = Leonid predictions for the period 2001–2100 | journal = WGN, Journal of the International Meteor Organization | volume = 35 | issue = 1 | pages = 5–12 | date = 2007 |bibcode = 2007JIMO...35....5M }}; also see {{Cite web | publisher = M. Maslov webpage | title = Leonids 1901–2100 | url = http://feraj.ru/Radiants/Predictions/1901-2100eng/Leonids1901-2100eng.html | access-date = 28 September 2016 | archive-date = 1 October 2016 | archive-url = https://web.archive.org/web/20161001183832/http://feraj.ru/Radiants/Predictions/1901-2100eng/Leonids1901-2100eng.html | url-status = live }}
See also
- List of meteor showers
- "Stars Fell on Alabama", based on the 1833 Leonid shower
- Perseids, associated with the comet Swift–Tuttle
References
{{Reflist|refs=
|title = 2023 Meteor Shower List
|publisher = American Meteor Society (AMS)
|url = https://www.amsmeteors.org/meteor-showers/2020-meteor-shower-list/
|accessdate = 2023-09-10}}
}}
Further reading
- {{cite journal
| author=Steven J. Dick
| title =Observation and interpretation of the Leonid meteors over the last millennium
| journal =Journal of Astronomical History and Heritage
| volume =1
| issue =1
| pages =1–20
| date =June 1998
| doi =10.3724/SP.J.1440-2807.1998.01.01
| issn =1440-2807
| bibcode=1998JAHH....1....1D}}
- {{cite book|author=Mark Littmann|title=The Heavens on Fire: The Great Leonid Meteor Storms|url=https://books.google.com/books?id=dLcMwEDURRUC|date=9 September 1999|publisher=Cambridge University Press|isbn=978-0-521-77979-1}}
External links
{{Commons category|Leonids}}
- [https://skyandtelescope.org/observing/celestial-objects-to-watch/the-discovery-of-the-perseid-meteors/ The Discovery of the Perseid Meteors] (after the Leonids and) Prior to 1837, nobody realized the Perseids were an annual event, by Mark Littmann
- [https://www.spaceweather.com/meteoroutlook/lunarleonids.html Lunar Leonids: Encounters of the Moon with Leonid dust trails] by Robert H. McNaught
- [https://leonid.arc.nasa.gov/meteor.html NASA: Background facts on meteors and meteor showers]
- [https://leonid.arc.nasa.gov/estimator.html NASA: Estimate the best viewing times for your part of the world]
- [https://www.space.com/3117-hear-leonid-meteor-shower.html How to hear the Leonid Meteor Shower]
- [http://www.oarval.org/leonids.htm Observatorio ARVAL – The Leonid Meteors]
- [https://web.archive.org/web/20110716051127/http://www.shadowandsubstance.com/Leonids/Leonids.html Animation of the Leonid Meteor Shower] at shadow&substance.com
{{Meteor showers}}
{{Authority control}}