Alpha Capricornids

Alpha Capricornids
Celestial map of Capricornus
Discovery date	1871
Parent body	169P/NEAT (2002 EX12)[1]
Radiant
Constellation	Capricornus
Right ascension	20h 44m 00s
Declination	−10° 00′ 00″
Properties
Occurs during	July 7 to August 15[2]
Date of peak	July 31[2]
Velocity	23 km/s
Zenithal hourly rate	5
See also: List of meteor showers

Alpha Capricornids is a meteor shower that takes place as early as 7 July and continues until around 15 August.^[2] The meteor shower was discovered by Hungarian astronomer Miklos von Konkoly-Thege in 1871.^[3] 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.^[1] 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.^[1] 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 2220–2420 A.D., one that will be "stronger than any current annual shower."^[1]

• Interactive visualization of Alpha Capricornids meteor stream
• -4 magnitude Alpha Capricornid shooting past Delphinus on July 17, 2006. Sigma 20 mm f/1.8