Eta-Aquariids

Meteor shower Eta-Aquariids
activity
Beginning	April 19th
maximum	5th of May
The End	28th of May
Radian position
RA	22 h 32 m
DE	−1 °
ZHR	50
Population index	2.4
geocentric speed	66 km / s

The Eta-Aquariids (also called May-Aquariids ) are a medium-strength meteor shower that can be seen every year in May. They come from Halley's Comet , for which sightings have been proven for more than two millennia. The name "Aquariids" goes back to the Latin name of the constellation Aquarius .

The Eta-Aquariids can only be observed from Central Europe in the last hour before dawn . But because its radiant - near the star Eta Aquarii - only reaches a small height above the horizon , the meteors of the Eta-Aquariids have a flat angle of entry into the atmosphere , which means that the meteor orbits in the sky often appear remarkably long. At a radian height of 10 degrees, less than 20 percent of the meteors will be visible compared to the zenith position, i.e. H. from a ZHR around 65, the observer can actually see a maximum of 10–15 current meteors per hour. Further south the conditions improve noticeably, because both the duration of the night and the height of the radiant in the possible observation window increase. In the Canary Islands , for example , you can effectively use around three hours and the radiant reaches more than 30 degrees at the end.

On May 6, 2013, a maximum ZHR of 100 was observed. According to model calculations by Mikiya Sato, the activity is primarily due to meteoroids that occurred during the perihelion passage of comet 1P / Halley in 1197 BC. u. Z. and 910 BC u. Z. were released and this time came close to the earth.

Individual evidence

1. ↑ IMO Meteor Shower Calendar 2020 , accessed April 16, 2020
2. ↑ imo.net: VMDB Meteor Shower Visual Campaigns , accessed on September 5, 2019
3. ↑ Global Radio η Aquarids 2013 ( Memento from January 6, 2014 in the Internet Archive )
4. ↑ η Aquarids 2013 ( Japanese )