Alpha Capricornids

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Alpha Capricornids
Capricornus constellation map.svg
Celestial map of Capricornus
Discovery date1871
Parent body169P/NEAT
(Minor planet 2002 EX12)
Right ascension20h 44m 00s
Declination−10° 00′ 00″
Occurs during15 July to 10 August
Date of peak29 July
Velocity23 km/s
Zenithal hourly rate5
See also: List of meteor showers

Alpha Capricornids is a meteor shower that takes place as early as 15 July and continues until around 10 August.[1] The meteor shower was discovered by Hungarian astronomer Miklos von Konkoly-Thege in 1871. This shower has infrequent but relatively bright meteors, with some fireballs. Parent body is comet 169P/NEAT.

Peter Jenniskens and Jeremie Vaubaillon identified the parent body as asteroid 2002 EX12, which in the return of 2005 was found weakly active near perihelion.[2] This object is now called comet 169P/NEAT.

According to Jenniskens and Vaubaillon, the meteor shower was created about 3,500 to 5,000 years ago, when about half of the parent body disintegrated and fell into dust.[2] The dust cloud evolved into Earth's orbit recently, causing a shower with peak rates of 2-5/h, sometimes having outbursts of bright flaring meteors with rates up to 5-9/h.

The bulk of the dust will not be in Earth's path until the 24th century. The Alpha Capricornids are expected to become a major annual storm in 22202420 A.D., one that will be "stronger than any current annual shower."[2]


  1. ^ "Alpha Capricornids: Encyclopedia Article". Encarta. Archived from the original on 19 April 2009. Retrieved 8 July 2014.
  2. ^ a b c "Minor planet 2002 EX12 ( = 169P/NEAT) and the Alpha Capricornid shower". Astronomical Journal. Retrieved 8 July 2014. Minor planet 2002 EX12 ... is identified as the parent body of the alpha Capricornid shower, based on a good agreement in the calculated and observed direction and speed of the approaching meteoroids for ejecta4500–5000 years ago....The bulk of this matter still passes inside Earth's orbit, but will cross Earth's orbit 300 years from now. As a result, the alpha Capricornids are expected to become a major annual shower in 2220-2420 A.D., stronger than any current annual shower

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