Geminids

Geminids (GEM)
The Geminids meteor shower as seen from the Northern Hemisphere, in December 2013
Pronunciation/ˈɛmənədz/
Discovery date1862[1]
Parent body3200 Phaethon[2]
Radiant
ConstellationGemini (near Castor)
Right ascension07h 28m [2]
Declination+32°[2]
Properties
Occurs during4 December – 17 December[2]
Date of peak14 December[2]
Velocity35[3] km/s
Zenithal hourly rate120[2]
See also: List of meteor showers

The Geminids are a prolific meteor shower caused by the object 3200 Phaethon,[4] which is thought to be a Palladian asteroid[5] with a "rock comet" orbit.[6] This would make the Geminids, together with the Quadrantids, the only major meteor showers not originating from a comet. The meteors from this shower are slow moving, can be seen in December and usually peak around December 4–16, with the date of highest intensity being the morning of December 14. Recent showers have seen 120–160 meteors per hour under optimal conditions, generally around 02:00 to 03:00 local time. Geminids were first observed in 1862,[1] much more recently than other showers such as the Perseids (36 AD) and Leonids (902 AD).

Based on data from the Parker Solar Probe, a 2023 study proposed that the Geminids may have been formed by the catastrophic breakup of a comet that formed asteroids 2005 UD and 1999 YC in addition to Phaethon.[7][8]

Background[edit]

The Geminid meteor shower is unique among celestial events as it originates not from a comet but from the asteroid 3200 Phaethon, discovered on Oct. 11, 1983, by the Infrared Astronomical Satellite. Phaethon's 1.4-year orbit around the Sun and its comet-like elliptical trajectory have led scientists to speculate if it is a "dead comet" or a distinct celestial entity known as a "rock comet." Despite its comet-like orbit, Phaethon lacks a cometary tail and exhibits spectra resembling a rocky asteroid. The Geminid meteoroids formed from Phaethon are denser (2–3 g/cm3) than typical cometary dust flakes (0.3 g/cm3). Named after the Greek mythological figure who drove the Sun-god Helios' chariot, Phaethon's discovery was attributed to astronomer Fred Whipple.[9]

Radiant[edit]

A Geminid meteor in 2007, seen from San Francisco
Asteroid (3200) Phaethon, parent body of the Geminids, imaged on December 25, 2010, with the 37 cm F14 Cassegrain telescope of Winer Observatory, Sonoita (MPC 857)

The meteors in this shower appear to come from the radiant in the constellation Gemini (hence the shower's name). However, they can appear almost anywhere in the night sky, and often appear yellowish in hue. Well north of the equator, the radiant rises about sunset, reaching a usable elevation from the local evening hours onwards. In the southern hemisphere, the radiant appears only around local midnight or so. Observers in the northern hemisphere will see higher Geminid rates as the radiant is higher in the sky.[10] The meteors travel at medium speed in relation to other showers, at about 22 miles per second (35 km/s), making them fairly easy to spot. The Geminids are now considered by many to be the most consistent and active annual shower. Geminids disintegrate while at heights above 24 miles (39 km).[11]

Animated GIF of a Geminid meteor falling earthwards

Timeline[edit]

Year Peak of shower ZHRmax Lunar phase[12]
2006 December 14 115[13] 33% waning crescent
2007 December 15 122[14] 30% waxing crescent
2008 December 14 139[15] 95% full moon
2009 December 13 120[16] 9% new moon
2010 December 14 127[17] 59% first quarter
2011 December 14 198[18] 86% waning gibbous
2012 December 14[3] 109[19] 2% new moon
2013 December 14[20] 134[21] 92% full moon
2014 December 14[22] 253[23] 50% last quarter
2015 December 14 120[24] 10% waxing crescent
2016 December 13 25[25] 100% full moon
2017 December 14 145[26] 13% waning crescent
2018 December 14 125±9[27] 41% waxing crescent
2019 December 14 120[28] 94% waning gibbous
2020 December 13 120[29] 2% waning crescent
2021 December 13 125±25[30] 73% waxing gibbous
2022 December 14 120 72% waning gibbous
2023 December 13 150[31] 0% waxing crescent

See also[edit]

References[edit]

  1. ^ a b Kronk, Gary W. "Observing the Geminids". Meteor Showers Online. Archived from the original on 17 May 2008. Retrieved 14 November 2012.
  2. ^ a b c d e f Moore, Patrick; Rees, Robin (2011), Patrick Moore's Data Book of Astronomy (2nd ed.), Cambridge University Press, p. 275, ISBN 978-0-521-89935-2.
  3. ^ a b "IMO Meteor Shower Calendar 2012: Geminids (GEM)". International Meteor Organization. Retrieved 2012-12-13.
  4. ^ Marsden, Brian G. (25 October 1983). "IAUC 3881: 1983 TB and the Geminid Meteors; 1983 SA; KR Aur (Circular No. 3881)". Central Bureau for Astronomical Telegrams. Archived from the original on 1 May 2012. Retrieved 18 May 2009.
  5. ^ Victoria Jaggard (2010-10-12). "Exploding Clays Drive Geminids Sky Show?". National Geographic Society. Archived from the original on 2012-12-13. Retrieved 2010-10-18.
  6. ^ Jewitt, David; Li, Jing (2010). "Activity in Geminid Parent (3200) Phaethon". The Astronomical Journal. 140 (5): 1519–1527. arXiv:1009.2710. Bibcode:2010AJ....140.1519J. doi:10.1088/0004-6256/140/5/1519. S2CID 6446528.
  7. ^ Cukier, W. Z.; Szalay, J. R. (June 1, 2023). "Formation, Structure, and Detectability of the Geminids Meteoroid Stream". The Planetary Science Journal. 4 (6): 109. arXiv:2306.11151. doi:10.3847/psj/acd538. ISSN 2632-3338.
  8. ^ Rayne, Elizabeth (June 27, 2023). "We finally know how the mysterious Geminid meteor shower originated". Ars Technica. Retrieved June 29, 2023.
  9. ^ "Geminids – NASA Science". science.nasa.gov. Retrieved 2023-12-12.
  10. ^ "Radiant (Northern vs Southern)". NASA Meteor Watch on Facebook. 2012-12-12. Retrieved 2012-12-14.
  11. ^ "NASA All Sky Fireball Network: Geminid End Heights". NASA Meteor Watch on Facebook. 2012-12-11. Retrieved 2012-12-11.
  12. ^ "Moongiant". www.moongiant.com.
  13. ^ "Geminids 2006: visual data quicklook". International Meteor Organization. 25 April 2007. Archived from the original on 24 December 2012. Retrieved 13 December 2012.
  14. ^ "Geminids 2007: visual data quicklook". International Meteor Organization. 10 August 2008. Archived from the original on 17 December 2012. Retrieved 13 December 2012.
  15. ^ "Geminids 2008: visual data quicklook". International Meteor Organization. 2 January 2009. Archived from the original on 2 February 2013. Retrieved 13 December 2012.
  16. ^ "Geminids 2009: visual data quicklook". International Meteor Organization. 19 April 2010. Archived from the original on 17 December 2012. Retrieved 13 December 2012.
  17. ^ "Geminids 2010: visual data quicklook". International Meteor Organization. 2012-09-19. Archived from the original on 2012-11-03. Retrieved 2012-12-13.
  18. ^ "Geminids 2011: visual data quicklook". International Meteor Organization. 2012-01-18. Archived from the original on 2012-12-28. Retrieved 2012-12-13.
  19. ^ "Geminids 2012: visual data quicklook". International Meteor Organization. 2012-12-21. Archived from the original on 2013-09-17. Retrieved 2013-10-11.
  20. ^ "IMO Meteor Shower Calendar 2013: Geminids (GEM)". International Meteor Organization. Retrieved 2013-10-11.
  21. ^ "Geminids 2013: visual data quicklook". International Meteor Organization. 2013-12-21. Archived from the original on 2013-12-16. Retrieved 2014-01-06.
  22. ^ "IMO Meteor Shower Calendar 2014 – Geminids". International Meteor Organization. Archived from the original on 10 September 2015. Retrieved 4 September 2015.
  23. ^ "Geminids 2014: visual data quicklook". International Meteor Organization. Archived from the original on 24 September 2015. Retrieved 4 September 2015.
  24. ^ "Meteor Showers 2015". NASA.
  25. ^ Lunsford, Robert. "Viewing the Geminid Meteor Shower in 2016". AMS.
  26. ^ Antier, Karl. "Impressive 2017 Geminids!". IMO.
  27. ^ Miskotte, Koen. "The Geminids of 2018: an analysis of visual observations". Meteor News.
  28. ^ Dickinson, David. "December Meteor Squalls: Prospects for the 2019 Geminids and Ursids". Universe Today.
  29. ^ Rice, Doyle. "The Geminid meteor shower, famous for producing fireballs, peaks this weekend". USA Today.
  30. ^ "Best meteor shower of the year: Geminids peak tonight, boasting 100–150 shooting stars". ABC7 San Francisco. 12 December 2021.
  31. ^ "Viewing the Geminid Meteor Shower in 2023". International Meteor Organization. 13 December 2023.

External links[edit]