κ-Cygnids 2009: 3 Αυγ. ως 25 Αυγ. Μέγιστο: 17 Αυγ.

[Bi2L]

πηγη imo.net

http://www.imo.net/calendar/2009#julsep

κ-Cygnids (KCG)

Active: August 3-25

Maximum: August 17 (λo = 145°)

ZHR = 3

Radiant: α = 286° δ = +59°

Radiant drift: see Table 6

v∞ = 25 km/s; r = 3.0

IFC: α = 330° δ = +60° and α = 300° δ = +30° (β > 20° N)

 

The waning crescent Moon creates no problems for viewing the expected κ-Cygnid peak this year from northern hemisphere sites, where the shower is chiefly accessible. Its r-value suggests telescopic and video observers may benefit from the shower's presence, but visual and photographic workers should note that occasional slow fireballs from this source have been reported too. The almost stationary radiant results from its close proximity to the ecliptic north pole in Draco. There has been some suggestion of a variation in its activity at times, perhaps coupled with a periodicity in fireball sightings, but more data are needed on a shower that is often ignored in favour of the major Perseids during August.

 

πηγη popastro.com

http://www.popastro.com/sections/meteor/meteor-aug2009.htm

The minor κ Cygnid maximum should happen on August 17, with a waning crescent Moon that should cause watchers few problems. The shower produces wonderfully slow, typically bright, meteors from August 3-25, but its peak ZHRs are just ~3. Occasional fireballs have been seen from it, and these may recur in periodic bursts every 6 or 7 years. In addition, because the shower's radiant, between Cygnus' western wing-tip and Draco's neck (at RA 19h04m, Dec +59° on August 17), is almost overhead for much of the night, observed rates can equal the ZHR in dark, clear skies at the peak. As the radiant lies close to the ecliptic pole in Draco, its daily drift is thought to be almost negligible. The shift in position from August 3 to 25 is from RA 18h50m, Dec +58° to RA 19h16m, Dec +60°.

 

 

 

 

 

The Kappa Cygnid Meteor Shower - Gary Kronk

http://www.examiner.com/x-8054-St-Louis-Astronomy-Examiner~y2009m8d14-The-Kappa-Cygnid-Meteor-Shower

The Kappa Cygnid meteor shower is not one of the spectacular meteor showers of the year. It is also not a famous meteor shower. In fact, on average, it only produces meteor displays of 4-5 per hour at maximum. So, why am I bothering to talk about this shower?

 

First, the Kappa Cygnids mark the end of the summer season for meteor showers, which I have covered during the last few weeks. Second, the Kappa Cygnids are an interesting minor shower that can throw an occasional surprise at observers.

 

The summer meteor season began in mid-July, when meteors started streaking from the constellations of Aquarius and Capricorn. The season peaked during the period of August 11-13 when the Perseid meteor shower was at its best. The Kappa Cygnids peak on the night of August 17 and represent the final annually visible shower of this exciting period.

 

What do we know about the Kappa Cygnids and what can you expect to see?

 

This meteor shower was discovered by N. de Konkoly (Hungary) on the night of 1874 August 11-12. He was observing the Perseid meteor shower, but noted several meteors coming from the Cygnus region. Other observers began watching the shower during the years that followed. During the 20th century, this shower has been observed visually, photographically, and by radio-based techniques. Astronomers have learned a lot.

 

The Kappa Cygnids peak on August 17. The meteor stream from which the meteors emanate is situated in an orbit that is highly inclined to the plane of the solar system. Such an orbit normally produces a short-duration meteor shower, since it doesn't take long for Earth to plow through it; however, meteors from the Kappa Cygnids can be seen from July 26 until September 1!

 

Such a long duration has led astronomers to believe that this is a very old meteor shower. Support for this theory is the fact that a minor planet has been found moving within the orbit of the Kappa Cygnids, instead of a comet. Comets produce clouds of dust that spread throughout their orbits. This dust appears as a meteor shower when Earth crosses the comet's orbit. The minor planet, which has been designated "2008 ED69" is believed to be the largest piece of a now defunct comet. It has been suggested that the shower was created 4000 to 6000 years ago.

 

This meteor shower experiences an unusual apparent variability in its hourly rates. Observers have reported through the years that, on the night of maximum, you are likely to see from 2 to 15 meteors per hour; however, what is a bit strange is that the Kappa Cygnids sometimes fail to make an appearance at all! For 2009, meteors from the Kappa Cygnid radiant have already been reported by several experienced observers while the Perseids were peaking, so they are already active as I write this article.

 

What is the "occasional surprise" that I mentioned earlier? The Kappa Cygnids have the propensity to produce very dramatic, slow moving fireballs! The very reason I decided to write about the Kappa Cygnids was because I saw one of these on the evening of August 13. My wife and youngest son were watching the Perseid meteor shower. We were all lined up next to each other in reclining lawn chairs in our back yard. My son started to say something to me and, in mid-sentence, suddenly shot his arm to the south (right across my face) and said "look!" My wife and I turned our heads and saw a bright white fireball slowly dropping toward the horizon. It was flickering a bit and vanished behind some trees. After it vanished, we noticed that it had left a faintly shimmering trail behind it that lasted for several seconds. This was the most spectacular meteor we saw that evening and was far brighter than anything else in the sky! This is why the Kappa Cygnids are worth watching.

 

I certainly don't want anyone to spend their time outside in vain and I can't promise that you will be equally rewarded. Anyone planning to observe this shower needs to have an ulterior motive.

 

So, on the night of August 17, you need to get away from city lights, lie back in a reclining lawn chair, and look straight up. If you start observing around 10:00, it will be fully dark and you will see the Milky Way streaming nearly overhead, extending from the northern part of the sky to the southern part. The constellation of Cygnus, from which the Kappa Cygnids originate, is located within the Milky Way and is also nearly overhead...at least for the majority of observers in the Northern Hemisphere. What this basically means is that if you have an unobstructed view of the sky, you are well situated for these meteors.

 

You also have to be patient. In addition to whatever Kappa Cygnids appear that evening, you are also likely to see the fading remnants of the Perseid shower and even a few meteors from Aquarius. Look at the Milky Way. It is more than a simple band of light stretching across the sky. Millions of stars make up the Milky Way and you can see dark steaks cutting across it in places. If you carefully look at the bright stars speckled across the sky, you will see that some are blue, white, yellow, and reddish-orange. To the east-southeast you will see a very bright object, which is actually the planet Jupiter, the largest planet in our solar system.

 

Various ancient cultures looked at the sky and saw patterns. They said the stars formed the shapes of great hunters, animals, insects, and mythological boats. What patterns do the stars form when you look at the sky? With no knowledge of astronomy, you can enjoy the night sky.

 

Oh yes, and don't forget to enjoy the meteors!

 

 

περισσοτερα: http://meteorshowersonline.com/showers/kappa_cygnids.html

 

η φωτογραφια ΔΕΝ ειναι για το 2009

[nansy]

Ευχαριστούμε Bi2L εξαιρετική η ενημέρωση σου!!

 

Εν ολίγοις θα είναι ορατό από Ελλάδα?? Αυτό που μου έκανε εντύπωση είναι η διάρκεια του!!Πολύ μεγάλη θα έλεγα..Επίσης 4-5 μετεωρίτες ανά ώρα..και πόσοι από αυτούς θα είναι ορατοί,με βάση τις συνθήκες κάθε πόλης...

 

Πάντως πάρα πολύ καλά τα άρθρα!!