bootidi attività anomala notte 23-24 giugno 2010?

Ciao a tutti,

su "meteorobs" è stata segnalata da Javor Kac, un attività anomala delle bootidi ( sciamo noto per occasionali outburst ), nella notte fra il 23-24 giugno. Qualcuno ha rilevato qualcosa?

Riporto il suo messaggio:

"Hi All,

significant June Bootids activity was noticed during comet observing
session on June 24, 2010, between 00h00m UT and 01h06m UT.
During one hour of casual observing (about 30-40% time was spent
skygazing) under LM 6.0 sky, eight June Bootids were seen by Jure Atanackov
a couple of other observers and myself.
Their magnitude distribution was:
0(2) +1(2) +2(2) +3(2)
During this interval only two sporadic meteors were seen.

My meteor camera Orion1 detected 9 June Bootids and 8 sporadic meteors in
about 5 hours observing time in the night of June 23/24.

American observers should be alert for the possible prolonged activity. I
hope some of you will persist despite the bright Moon!

Clear skies!
Javor "


Tradotto con Google :

Ciao a tutti,

significativa attività delle Bootidi di giugno è stato notato durante una sessione osservativa della cometa del 24 giugno 2010, tra UT 00h00m e 01h06m UT.
Durante un'ora di osservazione casuale (circa il 30-40% del tempo è stato speso
skygazing) sotto LM 6,0 cielo, otto Bootidi giugno sono stati visti da Jure Atanackov
un paio di altri osservatori e il sottoscritto.
La loro distribuzione magnitudo è stata:
0 (2) +1 (2) +2 (2) +3 (2)
Durante questo intervallo si sono viste solo due meteore sporadiche.

La mia meteor camera Orion1 ha rilevato 9 Bootidi e 8 meteore sporadiche in
circa 5 ore di tempo osservando la notte del 23/24 giugno. "

Si, riprese 6 BOO di Giugno. Aspetto prima di fornire un quadro più preciso.

Diego,

sarebbe interessante ( tu che hai diverse stazioni video ) un bel rapporto complessivo.

Attendiamo fiduciosi

Ferruccio

Ferruccio Zanotti ha scritto:

Diego,

sarebbe interessante ( tu che hai diverse stazioni video ) un bel rapporto complessivo.

Attendiamo fiduciosi

Ferruccio

Ancora è presto, aspetto fine mese, anche perchè il massimo del 27.06, coincide con la ciclicità (ogni 6 anni) dello sciame.

Il massimo è previsto per il 27, ma per la notte scorsa erano previsti incontri con nubi di particelle associate a questo sciame...




Dal sito dell'IMO, le previsioni per quest'anno:

June Boötids (JBO)
Active: June 22–July 2; Maximum: June 27, 14h30m UT (λo = 95 .◦7), but see text;
ZHR = variable, 0–100+;
Radiant: α = 224◦, δ = +48◦; Radiant drift: see Table 6;
V∞ = 18 km/s; r = 2.2;
TFC: α = 156◦, δ = +64◦ and α = 289◦, δ = +67◦ (β = 25◦–60◦ N).


This source was reinstated on the Working List after its unexpected return of 1998, when ZHRs of 50–100+ were visible for more than half a day. Another outburst of similar length, but with ZHRs of ~ 20–50 was observed on 2004 June 23, a date before definite activity had previously been recorded from this shower. Consequently, the shower’s start date was altered to try to ensure future activity so early is caught, and we encourage all observers to routinely monitor throughout the proposed activity period, in case of fresh outbursts. Prior to 1998, only three more probable returns had been detected, in 1916, 1921 and 1927, and with no significant reports between 1928 and 1997, it seemed likely these meteoroids no longer encountered Earth. The dynamics of the stream were poorly understood, although recent theoretical modelling has improved our comprehension. The shower’s parent, Comet 7P/Pons-Winnecke, has an orbit that now lies around 0.24 astronomical units outside the Earth’s at its closest approach. Its most recent perihelion passage was in 2008 September. Clearly, the 1998 and 2004 returns resulted from material shed by the comet in the past which now lies on slightly different orbits to the comet itself. Dust trails laid down at various perihelion returns during the 19th century seem to have been responsible for the last two main outbursts. Four similar dust trails are predicted to encounter the Earth this year, laid down by the comet in 1819, 1825, 1830 and 1836, which may produce UT maxima around June 24, 03h53m,01h22m, 00h07m and June 23, 22h40m respectively. Activity is uncertain, but is not expected to be particularly high, so perhaps will be no better than at the 2004 return. Conditions for checking are very unfavourable from the mid-northern latitudes where the radiant is best-seen, with full Moon on June 26, aside from the prolonged – in some places continuous – twilight, but it is important to discover whether activity recurs at all, and if so when. The radiant is usefully accessible virtually all night, and all observing techniques can be employed. In terms of the apparently ‘early’ predicted peaks this time, VID suggested some June Boötids may be visible in most years around June 20–25, but that their activity was largely negligible except near λo = 92◦ (2010 June 23). Even stranger was that this activity originated from a radiant about ten degrees south of the visual one found in 1998 and 2004, close to α = 216◦, δ = +38◦.