Understanding Meteor Showers the Pleiades the Perseid and more

We know that spring showers bring May flowers, but what about meteor showers? Well for Earth, it’s a light show that is even greater than fireworks at the Fourth of July.

Wish Upon a Shooting Star

Interplanetary space is littered with rocks that are called meteoroids. These rocks are debris left behind by comets, and usually wander aimlessly about space. However, it is not uncommon for a meteoroid to pass through the Earth’s atmosphere. When this occurs, the meteoroid is heated to incandesce due to the atmosphere’s friction, and leaves a visible trail. As soon as it enters the Earth, it is no longer referred to as a meteoroid, but a meteor. Meteors are more commonly known as shooting stars, as they literally shoot across the sky, making it difficult to spot them in the immense night sky. However, meteors are certainly not stars, and should not be mistaken for one either.

Most meteors are only tiny specks of dust that rapidly burn up in the atmosphere. However, fireballs are meteors that are larger and brighter, and may even explode, with an audible sound on the ground. If a meteor is able to pass through Earth’s atmosphere and land, it given yet another name; a meteorite.

The Sky is Falling!

Meteors actually enter our atmosphere on a regular basis, but spotting one can be difficult. On a normal night you may be able to see a few sporadic ones per an hour. However, at certain times during the year, the rate of observable meteors is much higher. These periods, called meteor showers, occur annually and are thought to be associated with the Earth encountering a large number on meteoroids in a particular part of its orbit where a comet has passed through.

As a number of comets travel around the Sun in an elliptical orbit, many different meteor showers occur within the same year. During specific meteor showers, the majority of the meteors can be found in a particular constellation, which is called the radiant of the shower. Meteor showers are often named after the radiant in which they are found. The Leonid Meteor Shower occurs within the constellation, Leo, while the Perseid Meteor Shower can be seen in the constellation Perseus. So, if you are familiar with these constellations, you should definitely be on a look out for any meteor showers that occur every year.

Mark Your Calendars

Since the orbits of some comets are very well known, it is possible to predict when a particular meteor shower will take place each year. Although many occur within each year at particular dates, the major meteor showers are the Quadrantids, Perseids, Orionids, Leonids, and Geminids.

The Quadrantids occurs around January 4. This meteor shower is named after the constellation Quadrans Muralis, which is found between Draco, Hercules, and Bootes. The Quadrantids is one of the best meteor showers, producing around 50 to 120 meteors per an hour, but because it takes place during the winter, it is observed very seldom. This meteor shower is also quite brief, lasting only a few hours.

The Perseids, on the other hand, happens when the weather is much warmer, between mid-July – August, its peak being on August 12. This meteor shower is named after the constellation, Perseus. The meteors that usually occur per an hour are around 68 and the debris that the meteors come from are also from Comet 1862 III.

The Orionids and the Leonids can be viewed during the Autumn seasons. The Orionids, which occur near the constellation Orion, usually happen around October 21, while the Leonids, whose radiant is around the constellation Leo, happens around November 17. The meteors that are seen during the Orionids are a result of the debris left behind from the infamous Comet Halley and around 30 meteors can be observed within an hour. The Leonids’ parent comet is Comet P/Tempel-Tuttle and usually only 10 meteors occur within an hour.

The last major meteor shower that occurs within the year is around December 14. The Geminids, whose radiant is around the constellation, Gemini, has around 58 meteors per an hour and its parent comet is the 3200 Phaethon.

All of these meteor showers and other meteor showers as well, can occur on multiple days around a given date, as most meteor showers tend to last a few nights. So, don’t be afraid that you will miss a meteor shower on a particular day, as these type of things aren’t hits and miss. And you don’t even need a telescope or any other fancy material, as meteors are perfectly visible with the naked eye. All in all, meteor showers are a perfect past time not only during the summer, but any time during the year.

Resources:

http://liftoff.msfc.nasa.gov/academy/space/solarsystem/meteors/meteors.html
http://csep10.phys.utk.edu/astr161/lect/meteors/showers.html
http://dictionary.reference.com/browse/meteor
http://dictionary.reference.com/browse/comet
http://en.wikipedia.org/wiki/Perseids