A meteor shower is currently active that will peak on the morning of May 6. Known as the Eta Aquarids, the shower is interesting because it was created by the famous Halley's Comet, but it is one of the more difficult showers to observe.
The Eta Aquarids were independently discovered in 1870 by G. L. Tupman (sailing in the Mediterranean Sea) as well as several members of the Italian Meteoric Association (IMA). The discovery came at a time when meteor observers had started plotting each meteor that they saw on star charts. After several days of observing, these plots could be extended backwards to reveal active meteor showers. For 1870, the records of Tupman and the IMA revealed the activity was confined to the period of April 29 to May 5.
The discovery of the Eta Aquarids solved a minor mystery. Seven years prior to the observations in 1870, astronomer H. A. Newton had explored historical texts going back more than 1500 years. He had found meteor showers were recorded during April 28-30 on several occasions during the period of AD 401 to 1009. These periods of activity were quickly linked to the Eta Aquarids.
A few years after the 1870 discovery, A. S. Herschel made an interesting discovery. He conducted a mathematical survey to find which comets were likely to produce meteor showers. He found that Earth was closest to the orbit of Halley's Comet on May 4th of every year. Herschel quickly noted that Tupman's observations indicated the area from which the meteor shower radiated was quite close to what would be expected for Halley's Comet and so the link was established.
From the time of the discovery of the Eta Aquarids up to the present, it has been recognized that this is not the easiest meteor shower to observe each year. The shower is not visible throughout the night like some showers. Instead, the Eta Aquarids are best observed for a couple of hours prior to the beginning of morning twilight…with the final hour being the best.
Observers in the Northern Hemisphere can expect to see about 10 meteors per hour, while observers in the Southern Hemisphere will see hourly rates near 30. The meteors will appear to move quite fast. The constellation Aquarius is located low over the southeast horizon before sunrise. If the meteors you see can be traced backwards to this area, you have probably seen an Eta Aquarid…a piece of Halleys Comet which was possibly ejected about 2000 years ago!
For more info: Check out Gary W. Kronk's Meteor Showers Online web page at http://meteorshowersonline.com/eta_aquarids.html.
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