Friday, May 7, 2010

Annual Meteor Showers

Here's a little something for the meteor watchers:

There are meteor showers that regularly occur in every year. How we know when and where this meteor showers occur is simple. There are streams of debris from comets that pass along the Earth's orbit. This debris are called meteoroids. Now, the Earth ends up almost at the exact position after one revolution. And because the Earth ends up in exactly the same place it reaches the meteoroid stream in almost exactly the same time and the same place in its orbit. When this stream of debris come in contact with the Earth's atmosphere, a meteor shower is produced.

To help you locate meteor showers, they are usually named after their radiant (i.e., Leonids meteor shower can be found in Leo; Delta Aquarids radiate from the delta star of Aquarius).
 Here is a list of the prominent meteor showers (visible to the Philippines). There are other showers aside from this but they have very low ZHRs.

Quadrantids Meteor Shower 
Quadrantids, as you may have noticed, does not resemble any of the 88 constellations. This is because the Quadrans Muralis, in which it is named from, is an obsolete constellation. This is located somewhere along Hercules, Bootes and Draco.
Peak: January 3/4
Active Period: January 1 - 6
ZHR (Zenithal Hourly Rate, the amount of meteors per hour during the peak): 90

Lyrids Meteor Shower
Originating from the debris of comet Thatcher. This meteor shower originates from the constellation Lyra which rises up in the east at around 11:30.
Peak: April 22
Active Period: April 19 - 24
ZHR: 12

Eta-Aquarids Meteor Shower
This meteor shower radiates from the Eta star of the constellation Aquarius. It's parent comet is the famous Halley's comet.
Peak: May 5/6
Active Period: May 1 - 8
ZHR: 45

Lyrids Meteor Shower (June Lyrids)
Another meteor shower originating from Lyra.
Peak: June 15/16
Active Period: June 10 -21
ZHR: 9 - 10

Delta Aquarids
Radiating from Aquarius' Delta star. It's parent comet is unknown. This shower produces bright yellow meteors.
Peak: July 28/29
Active Period: July 15 - Aug 15
ZHR: 19

This meteor shower produces bright yellowish fire balls. They strike the atmosphere slowly at an average of 15 miles per second.
Active Period: July 29 - 30
ZHR: 15

Perseids Meteor Shower
Originating from the comet Swift-Tuttle
Peak: Aug 12/13
Active Period: Jul 25 - Aug 18
ZHR: 80

Orionids Meteor Shower
Coming from the same meteoroid stream as Eta Aquarids, the Orionids belong to the debris of Halley's comet. Radiating from Orion, the hunter.
Peak: October 21
Active Period: Oct 16 - 26
ZHR: 25

Taurids Meteor Shower (and Leonids)
A fascinating meteor shower that appears as two showers in one. It is a combination of Taurids and Leonids. Comet Encke is the source of this shower and Comet Temple-Tuttle.
Peak: Nov 5 and 17/18
Active Period: Nov 4 - 7 and Nov 15 - 19
ZHR: 8 and 10

Geminids Meteor Shower
The most prominent and the most reliable of the annual meteor showers. This meteor shower comes from debris of the asteroid 3200 Phaeton. This shower creates a multi-colored display of meteors, most bright white, and then yellow, and then blue, red and green.
Peak: Dec 13/14
Active Period: Dec 17 - 15
ZHR: 80