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Perseids

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Perseids (PER)
Perseids in 2017 as seen from the White Desert, Egypt
Pronunciation/ˈpɜːrsi.ədz/[1]
Discovery dateAD 36 (first record)[2][3]
Parent bodyComet Swift–Tuttle[4]
Radiant
ConstellationPerseus and Cassiopeia
(near HD 19557)
Right ascension03h 13m [5]
Declination+58°[5]
Properties
Occurs duringJuly 14 – September 1[5]
Date of peakAugust 12
(August 13 for 2023)[5]
Velocity58.8[5] km/s
Zenithal hourly rate100[5]
See also: List of meteor showers

The Perseids are a prolific meteor shower associated with the comet Swift–Tuttle that are usually visible from mid-July to late-August. The meteors are called the Perseids because they appear from the general direction of the constellation Perseus and in more modern times have a radiant bordering on Cassiopeia and Camelopardalis.

Etymology

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The name is derived from the word Perseidai (Greek: Περσείδαι), the sons of Perseus in Greek mythology.

Characteristics

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The radiant point for the Perseid meteor shower
A meteoroid of the Perseids with a size of about ten millimetres entering the Earth's atmosphere in slow motion (x 0.1). The meteoroid is at the bright head of the trail, and the recombination glow of the ionised mesosphere is still visible for about 0.7 seconds in the tail.
(Variant of the animation in real time)
Video of two meteors of the Perseids within five seconds and a Starlink satellite in constellation Cygnus taken in International Dark Sky Reserve Westhavelland on 12 August 2020

The stream of debris is called the Perseid cloud and stretches along the orbit of the comet Swift–Tuttle. The cloud consists of particles ejected by the comet as it travels on its 133-year orbit.[6] Most of the particles have been part of the cloud for around a thousand years. However, there is also a relatively young filament of dust in the stream that was pulled off the comet in 1865, which can give an early mini-peak the day before the maximum shower.[7] The dimensions of the cloud in the vicinity of the Earth are estimated to be approximately 0.1 astronomical units (AU) across and 0.8 AU along the Earth's orbit, spread out by annual interactions with the Earth's gravity.[8]

The shower is visible from mid-July each year, with the peak in activity between 9 and 14 August, depending on the particular location of the stream. During the peak, the rate of meteors reaches 60 or more per hour. They can be seen all across the sky; however, because of the shower's radiant in the constellation of Perseus, the Perseids are primarily visible in the Northern Hemisphere.[9] As with many meteor showers the visible rate is greatest in the pre-dawn hours, since more meteoroids are scooped up by the side of the Earth moving forward into the stream, corresponding to local times between midnight and noon, as can be seen in the accompanying diagram.[10] While many meteors arrive between dawn and noon, they are usually not visible due to daylight. Some can also be seen before midnight, often grazing the Earth's atmosphere to produce long bright trails and sometimes fireballs. Most Perseids burn up in the atmosphere while at heights above 80 kilometres (50 mi).[11]

Peak times

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The 2010 Perseids over the ESO's VLT
Year Perseids active between Peak of shower
2023 July 14 – Sep 01 August 13 08:00 UT[12] (8% Waning Crescent Moon). Earth may have crossed the 69 BCE trail around August 14 02:00 UT.[13] The New Moon is on Aug 16.
2022 July 17 – August 24 August 12–13 (full moon on Aug 12)
2021 July 17 – August 24 August 11–12 (ZHRmax 150)[14]
2020 July 16 – August 23[15] August 12–13 (ZHRmax 100) (full moon on Aug 3)[15]
2019 July 17 – August 24 August 12–13[16] (ZHRmax 80) (full moon on Aug 15)
2018 July 17 – August 24 August 11–13[17] (ZHRmax 60)
2017 July 17 – August 24 August 12[18]
2016 July 17 – August 24 August 11–12 [19] (ZHRmax 150)
2015 July 17 – August 24 August 12–13[20] (ZHRmax 95) (new moon on Aug 14)
2014 July 17 – August 24 August 13 (ZHRmax 68)[21] (full moon on Aug 10)
2013 July 17 – August 24 August 12 (ZHRmax 109)[22]
2012 July 17 – August 24 August 12 (ZHRmax 122)[23]
2011 July 17 – August 24 August 12 (ZHRmax 58)[24] (full moon on Aug 13)[25]
2010 July 23 – August 24 August 12 (ZHRmax 142)[26]
2009 July 14 – August 24 August 13 (ZHRmax 173) (The estimated peak was 173,[27] but a gibbous Moon washed out fainter meteors.)
2008 July 25 – August 24[28] August 13 (ZHRmax 116)[28]
2007 July 19 – August 25[29] August 13 (ZHRmax 93)[29]
2006 August 12/13 (ZHRmax 100)[30]
2005 August 12 (ZHR max 90[31])[32]
2004 August 12 (ZHRmax >200)[33]
1994 (ZHRmax >200)[3]
1993 (ZHRmax 200–500)[3]
1992 August 11 (outburst under a full moon on Aug 13)[34]
1883 August 9 or earlier[35] August 11 (ZHRmax 43)[35]
1864 (ZHRmax >100)[3]
1863 (ZHRmax 109–215)[3]
1861 (ZHRmax 78–102)[3]
1858 (ZHRmax 37–88)[3]
1839 (ZHRmax 165)[3]

Historical observations and associations

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A Perseid in 2007

Some Catholics refer to the Perseids as the "tears of Saint Lawrence", suspended in the sky but returning to Earth once a year on August 10, the canonical date of that saint's martyrdom in 258 AD.[36] The saint is said to have been burned alive on a gridiron. His manner of death is almost certainly the origin of the Mediterranean folk legend claiming that the shooting stars are the sparks of Saint Lawrence's martyrdom. The legend holds that during the night of August 9 to 10, cooled embers appear in the ground under plants; these embers are known as the "coal of Saint Lawrence."[37][38]

The transition in favor of the Catholic saint and his feast day on August 10, moving away from pagan gods and their festivals — a process known as Christianization — was facilitated by the phonetic assonance of the Latin name Laurentius with Acca Larentia,[39] a goddess previously celebrated during the summer period alongside Priapus, as a fertility deity. Among the Romans, it was believed that the trails of the Perseids represented the benevolent rain of Priapus' seed[40] . In this context, the god's cosmogonic phallus acted as a life-giver, blessing the fields and promoting fertility. During the same period, phallic processions and other sexual rites were common. Christianity, which had a different relationship with sexuality and generativity compared to Greco-Roman culture, replaced this sexual connotation with a reference to martyrdom.[41]

In 1836 Adolphe Quetelet wrote: J'ai cru remarquer aussi une fréquence plus grande de ces météores au mois d'août (du 8 au 15) "I think I noticed also a greater frequency of these meteors in the month of August (from 8 to 15)."[42] After studying historical records, he predicted a peak on 10 August. He then wrote to other astronomers, who confirmed this prediction on the night of 10 August 1837. Quetelet missed the shower due to bad weather.[43]

In 1866, after the perihelion passage of Swift-Tuttle in 1862, the Italian astronomer Giovanni Virginio Schiaparelli discovered the link between meteor showers and comets.[43] The finding is contained in an exchange of letters with Angelo Secchi.

Observation from the International Space Station at Earth orbit
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In his 2006 novel Against the Day, American novelist Thomas Pynchon refers to the Perseid meteor shower being watched by three characters west of the Dolores Valley after playing a game of tarot. In the TV series Curious George, season 7 episode 1b, George and his friends Allie and Bill hunt for the Perseids, which they believe are creatures that look like purses. At the end of the episode, Allie's grandfather Mr. Renkins says that the Perseids is a meteor shower happening in early August.[44]

John Denver's song "Rocky Mountain High" references the showers with the lyric, "I've seen it raining fire in the sky."

See also

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References

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  1. ^ "Perseid". Merriam-Webster.com Dictionary. Merriam-Webster.
  2. ^ Bill Cooke; Danielle Moser & Rhiannon Blaauw (August 11, 2012). "NASA Chat: Stay 'Up All Night' to Watch the Perseids!" (PDF). NASA. p. 55. Archived from the original (PDF) on October 25, 2020. Retrieved August 16, 2013.
  3. ^ a b c d e f g h Gary W. Kronk. "Observing the Perseids". Meteor Showers Online. Archived from the original on July 19, 2018. Retrieved August 12, 2009.
  4. ^ Moore, Patrick; Rees, Robin (2011), Patrick Moore's Data Book of Astronomy (2nd ed.), Cambridge University Press, p. 275, ISBN 978-0521899352
  5. ^ a b c d e f "2023 Meteor Shower List". American Meteor Society (AMS). Retrieved August 5, 2023.
  6. ^ Dan Vergano (August 7, 2010). "Perseid meteor shower to light up night sky this weekend". Usatoday.com. Retrieved August 12, 2013.
  7. ^ Dr. Tony Phillips (June 25, 2004). "The 2004 Perseid Meteor Shower". Science@NASA. Archived from the original on March 20, 2010. Retrieved March 12, 2010.
  8. ^ D.W. Hughes (1996). "Cometary Dust Loss: Meteoroid Streams and the Inner Solar System Dust Cloud". In J. Mayo Greenberg (ed.). The Cosmic Dust Connection. Springer Science & Business Media. p. 375. ISBN 9789401156523.
  9. ^ "Perseids Meteor Shower 2018". timeanddate.com. Retrieved July 30, 2018.
  10. ^ "what is a meteor shower". Archived from the original on August 17, 2015. Retrieved July 20, 2015.
  11. ^ "NASA All Sky Fireball Network: Perseid End Height". NASA Meteor Watch on Facebook. August 11, 2012. Retrieved November 19, 2012.
  12. ^ Robert Lunsford. "Viewing the Perseid Meteor Shower in 2023". American Meteor Society (AMS). Retrieved August 6, 2023.
  13. ^ IMO Meteor Org [@IMOmeteors] (August 13, 2023). "☄️☄️You think 2023 Perseid meteor show is over? It's not!
    Next night, Perseid meteor shower rates should remain decent, and there is a probability the Earth will cross a dust trail released from 109P/Swift-Tuttle in 68 BC on Aug. 14, between 01h and 02h45 UT. Keep on observing!"
    (Tweet) – via Twitter.
  14. ^ Elizabeth Howell (August 14, 2021). "Perseid meteor shower of 2021 thrills skywatchers". Space.com. Retrieved August 12, 2024.
  15. ^ a b "Perseid meteor shower 2020: When and where to see it in the UK". Royal Museums Greenwich. July 23, 2020. Retrieved August 2, 2020.
  16. ^ "Perseid meteor shower 2019: When and where to see it in the UK". Royal Museums Greenwich. Retrieved August 3, 2019.
  17. ^ Sarah Lewin (July 9, 2018). "Perseid Meteor Shower 2018: When, Where & How to See It". Space.com. Retrieved July 20, 2018.
  18. ^ Sarah Lewin (July 26, 2017). "Perseid Meteor Shower 2017: When, Where & How to See It". Space.com. Retrieved July 27, 2017.
  19. ^ "Perseid Meteor Shower 2016: When, Where & How to See It". Retrieved July 18, 2016.
  20. ^ "Meteor Showers 2015". NASA. Archived from the original on December 24, 2019. Retrieved August 9, 2015.
  21. ^ "Perseids 2014: visual data quicklook". Imo.net. August 13, 2014. Archived from the original on October 24, 2016. Retrieved August 13, 2014.
  22. ^ "Perseids 2013: visual data quicklook". Imo.net. September 23, 2013. Archived from the original on October 24, 2016. Retrieved April 20, 2014.
  23. ^ "Perseids 2012: visual data quicklook". Imo.net. October 22, 2012. Archived from the original on April 21, 2014. Retrieved April 20, 2014.
  24. ^ "Perseids 2011: visual data quicklook". Imo.net. October 6, 2011. Archived from the original on November 6, 2013. Retrieved April 20, 2014.
  25. ^ "How to See the Best Meteor Showers of the Year: Tools, Tips and 'Save the Dates'". nasa.gov. Archived from the original on July 21, 2012. Retrieved November 16, 2010.
  26. ^ "How to See the Best Meteor Showers of the Year: Tools, Tips and 'Save the Dates'". nasa.gov. Archived from the original on July 21, 2012. Retrieved August 12, 2010.
  27. ^ "Perseids 2009: visual data quicklook". Imo.net. April 26, 2010. Archived from the original on October 16, 2016. Retrieved August 11, 2009.
  28. ^ a b "Perseids 2008: visual data quicklook". Imo.net. June 6, 2009. Archived from the original on October 24, 2016. Retrieved August 11, 2009.
  29. ^ a b Perseids 2007: first results Archived 2011-09-27 at the Wayback Machine
  30. ^ EAAS
  31. ^ "Perseids 2005, visual". IMO. August 25, 2005.
  32. ^ 22jul_perseids2005 Archived October 9, 2021, at the Wayback Machine NASA.gov
  33. ^ Żołądek, P.; et al. (October 2009), "The 2004 Perseid meteor shower – Polish Fireball Network double station preliminary results", Journal of the International Meteor Organization, 37 (5): 161–163, Bibcode:2009JIMO...37..161Z
  34. ^ Brown (1992). "The Perseids 1992. New outburst announces return of P/Swift-Tuttle". WGN. 20 (5): 192. Bibcode:1992JIMO...20..192B.
  35. ^ a b Corder, H (October 22, 1883). "1883Obs.....6..338C Page 338". Adsabs.harvard.edu. 6: 338. Bibcode:1883Obs.....6..338C. Retrieved November 3, 2018.
  36. ^ "Science: Tears of St. Lawrence". TIME. August 23, 1926. Retrieved August 12, 2009.
  37. ^ (in Italian) Falling stars and coal under the basil www.sanlorenzomaggiore.net
  38. ^ (in Italian) The Coal of Saint Lawrence balbianblog.blogspot.it
  39. ^ "SHOOTING STARS". utestudents BLOG.
  40. ^ Powell, J. (2017). "Observing Meteors and Meteor Showers". Cosmic Debris. Astronomers' Universe. Cham: Springer. pp. 179–216. doi:10.1007/978-3-319-51016-3_9. ISBN 978-3-319-51016-3.
  41. ^ (in Italian)"Alla scoperta di Castrum Inui" (PDF). Associazione Turistica Pro Loco Ardea. Archived from the original (PDF) on June 14, 2018. Retrieved August 14, 2024.
  42. ^ Annuaire de l'Observatoire Royal de Bruxelles, Volume 4, 1836, p272 (In French)
  43. ^ a b Sauval, J., "Quetelet and the Discovery of the First Meteor Showers", WGN, Journal of the International Meteor Organization, {25} February 1997, pp 21-33
  44. ^ "Curious George: Bright Lights Little Monkey".

General and cited references

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  • Littman, Mark, The Heavens on Fire: The Great Leonid Meteor Storms, Cambridge, Cambridge University Press, 1998. ISBN 0521624053. Chapter 6, "The Discovery of the August Meteors", pp. 83–100.
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