The annual Eta Aquariids meteor shower, occasionally written as Eta Aquarids, peaks on May 5th / 6th and this year's event is favourable as the waxing gibbous Moon will have set a few hours before sunrise. The shower is best seen in the early morning hours just before sunrise from southern and equatorial regions.
Parent Comet
The parent body for the Eta Aquariids meteor shower is Halley's comet (1P/Halley). This isn't the only annual shower associated with the famous comet, the Orionids in October also originate from the same source. Although Halley has now left the inner Solar System and won't return until 2061, it's worth remembering that every Eta Aquariids meteor is a small part of the famous comet burning up in the Earth's atmosphere.
Radiant
The radiant of the Eta Aquariids is located in Aquarius just south of the celestial equator and close to the Pegasus / Pisces border. For meteor watchers at equatorial and southern latitudes it appears quite high in the east / northeastern sky a few hours before sunrise. However, at mid-northern latitudes the radiant remains low down towards the east-southeast, even as morning twilight sets in.
Eta Aquariids Radiant and Star Chart - pdf format (credit:- freestarcharts)
What to expect in 2017
Up to 55 meteors per hour can be expected in the early hours of the morning from equatorial or southern latitudes. However, from northern temperate latitudes fewer meteors will be seen. On the positive side, the shooting stars are fast moving and often have long persistent trains. In addition, it's also worth looking out on the nights of May 4th / 5th and May 6th / 7th.
Eta Aquariids Data Table
Meteor shower name | Eta Aquariids |
---|---|
Meteor shower abbreviation | ETA |
Radiant constellation | Aquarius |
Activity | April 19th -> May 28th |
Peak Date | May 6th (no sharp peak) |
RA (J2000) | 22hr 32m |
DEC (J2000) | -01d |
Speed (km/s) | 66 |
ZHR | 55 (can vary between 40 and 85) |
Rating | Bright |
Parent body | 1P/Halley |
Notes | Unlike most major annual meteor showers, there is no sharp peak for this shower but rather a flat week of good rated centered on May 6th. |
Comet 1P/Halley Data Table (at epoch February 17th, 1994)
Name | 1P/Halley |
---|---|
Type | Comet |
Classification | Halley-type comet (NEO) |
Discoverer | Prehistoric, Edmond Halley first recognised the periodicity |
Discovery date | Prehistoric |
Aphelion (AU) | 35.0823 |
Perihelion(AU) | 0.58598 |
Semi-major axis (AU) | 17.8341 |
Eccentricity | 0.96714 |
Orbital period (years) | 75.3175 |
Inclination (degrees) | 162.263 |
Longitude of ascending node (degrees) | 58.4201 |
Last perihelion | February 9th, 1986 |
Next perihelion | July 28th, 2061 |
Notes | Halley's comet, the most famous of all comets |