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2015 Eta Aquarids

A good shower from the southern hemisphere, but is barely observable from the UK.

Main Activity Dates Apr 19 to May 28
Peak Rates May 5 - 6
Peak ZHR 50 - 70 
Best Observed Rates Pre-dawn on May 6
Visibility each night (UK) Very limited visibility - radiant doesn't rise until near dawn
Moonlight issues at Maximum Significant - Moon is 2 days past full, though low in the southern sky

 

 

 

 

 

The Eta Aquarid meteor shower - the post-perihelion encounter with the meteor stream of comet 1P/Halley - has tended to be ignored by UK observers. With the radiant only starting to rise above the eastern horizon late in the night (in morning twilight for observers in Scotland), few Eta Aquarid meteors, if any, are likely to be seen. 

In 2013, however, the Eta Aquarids sprang a surprise and several Eta Aquarid meteors were imaged from the UK by Alex Pratt (see http://www.popastro.com/meteor/reports/report.php?id_secRep=154 ) and William Stewart of the NEMETODE network (www.nemetode.org). This enhanced activity tied in with a last minute prediction from Mikiya Sato that the Earth would encounter several old filaments (from 8-11 centuries ago) in the Eta Aquarid meteor stream during May 6th. 

No enhancement of rates was expected or seen in 2014.

At maximum, the Eta Aquarid radiant lies at RA 22h32m , Dec -01  - in the top left corner of Aquarius (see the chart below)

Although the waning gibbous Moon on the Scorpius-Ophiuchus border will brighten the sky to some extent for the 2015 maximum, the effect on Eta Aquarid rates will be somewhat limited given that UK observers will be monitoring an eastern sky that is brightening as morning twilight encroaches.

Eta Aquarids are very swift meteors, often with long paths because of their low radiant, and fine persistent trains.