Eta Aquariids

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Eta Aquariids (ETA)
Discovery date 1870[1]
Parent body Halley's Comet[1]
Constellation Aquarius
(near Eta Aquarii)
Right ascension 22h 20m
Declination −01°
Occurs during April 21 – May 20
Date of peak May 6
Velocity 66 km/s
Zenithal hourly rate 30[1]
See also: List of meteor showers

The Eta Aquariids are a meteor shower associated with Halley's Comet.

The shower is visible from about April 21 to about May 20 each year with peak activity on or around May 6. Unlike most major annual meteor showers, there is no sharp peak for this shower, but rather a plateau of good rates that last approximately one week centered on May 7.[2] The meteors we currently see as members of the Eta Aquariid shower separated from Halley’s Comet hundreds of years ago. The current orbit of Halley’s Comet does not pass close enough to the Earth to be a source of meteoric activity.[2]

Although this shower is not as spectacular as the Leonids, it is not an ordinary event. The Eta Aquariids get their name because their radiant appears to lie in the constellation Aquarius, near one of the constellation's brightest stars, Eta Aquarii. The shower peaks at about a rate of around a meteor per minute, although such rates are rarely seen from northern latitudes due to the low altitude of the radiant.

The Eta Aquariids are best viewed in the pre-dawn hours away from the glow of city lights. For northern observers, the radiant of the shower is only above the horizon for the few hours before dawn, and early-rising observers are often rewarded with rates that climb as the radiant rises before sunrise. The shower is best viewed from the equator to 30 degrees south latitude.[2]

In 2005, the shower was favorably viewable because of a new moon on May 8. In 2011, the maximum of the shower was again favoured by a May 3 new moon, which meant that the period around maximum was visible in moon-free pre-dawn skies. In 2012 they were seen on May 6, 2012 along with a supermoon around dusk. On May 6, 2013 there was a 10% waning crescent moon in the pre-dawn sky.

See also[edit]


  1. ^ a b c Gary W. Kronk. "Observing the Eta Aquarids". Meteor Showers Online. Retrieved 2013-05-04. 
  2. ^ a b c Robert Lunsford. "Viewing the 2013 Eta Aquariid Meteor Shower". American Meteor Society. Retrieved 2013-05-04. 

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