Ωριωνίδες 2011(ORI): 2 Οκτ. ως 7 Νοεμ. Μέγ: 21 Οκτωβρίου

[Bi2L]

Orionids (ORI)

 

πηγή imo.net

Active: October 2 — November 7; Maximum: October 21 (λ⊙ = 208°); ZHR = 25;

Radiant: α = 95°, δ = +16°; Radiant drift: see Table 6;

V∞ = 66 km/s; r = 2.5;

TFC: α = 100°, δ = +39° and α = 75°, δ = +24° (β > 40° N);

or α = 80°, δ = +1° and α = 117°, δ = +1° (β < 40° N).

 

October's waxing Moon favours the Orionid peak in 2012 too. The shower's radiant, near the celestial equator, is at a useful elevation by around local midnight in either hemisphere, somewhat before in the north, so most of the world can enjoy the shower. Each return from 2006 to 2009 produced unexpectedly strong ZHRs of around 40—70 on two or three consecutive dates. An earlier IMO analysis of the shower, using data from 1984—2001, found both the peak ZHR and r parameters varied somewhat from year to year, with the highest mean ZHR ranging from ∼ 14—31 during the examined interval. In addition, a suspected 12-year periodicity in stronger returns found earlier in the 20th century appeared to have been partly confirmed. That suggested better returns in the 2008—2010 interval, falling thereafter towards 2014—2016, so perhaps with ZHRs of about 25 this year. The recent strong returns seem to have had a separate resonant cause, though nothing further is anticipated for 2012. The Orionids often provide several lesser maxima, helping activity sometimes remain roughly constant for several consecutive nights centred on the main peak. In 1993 and 1998, a submaximum about as strong as the normal peak was detected on October 17/18 from Europe, for instance. All observers should be aware of these possibilities, as circumstances are equally favourable for covering October 17/18 under dark skies this time too. Several visual subradiants had been reported in the past, but recent video work found the radiant to be far less complex.

[Bi2L]

Φυσικά υπάρχουν και ε-Διδυμίδες αλλά δεν ανοίγω νέο Θέμα αφού θα είναι μικρή βροχή, όποιος ενδιαφέρετε μπορεί να βρει εδω ότι θέλει imo.net - ε-Geminids (EGE)

(ίδια φωτογραφία με την παραπάνω)

 

ε-Geminids (EGE)

Active: October 14—27; Maximum: October 18 (λ⊙ = 205°); ZHR = 3;

Radiant: α = 102°, δ = +27°; Radiant drift: see Table 6;

V∞ = 70 km/s; r = 3.0;

TFC: α = 90°, δ = +20° and α = 125°, δ = +20° (β > 20° S).

A weak minor shower with characteristics and activity nearly coincident with the Orionids, so great care must be taken to separate the two sources, preferably by video or telescopic work, or perhaps visual plotting. The waxing crescent Moon gives no problems this year, as it will have set from either hemisphere before radiant-rise. Northern observers have a radiant elevation advantage, with observing practical from about midnight onwards. There is some uncertainty about the shower's parameters, with both visual and video data indicating the peak may be up to four or five days later than suggested above.

[Bi2L]

Up!

 

Έλα να προετοιμαζόμαστε! Αφου δεν μας έκαναν τη χάρη οι Δρακοντίδες ας ελπίσουμε να δούμε μερικούς Ωριωνίδες ετσι για το καλό

 

Εγω θα κάνω καταμέτρηση με το μάτι καθώς και καταγραφή με Dsrl και μια Watec στο Ufo Cap, φυσικά μακάρι να μας κάνει την χάρη ο καιρός.

[Bi2L]

Και ένας δοκιμαστικός Ωριωνίδης

 

(βέβαια θα πρέπει να ελέγξω άλλη μια φορά την πορεία του, αλλά και να μην είναι τουλάχιστον πέτυχαν οι δοκιμές)

[Bi2L]

Καταιγίδες εδώ... ούτε Ωριωνίδες δεν θα δούμε φέτος...