Finally, on Friday, we also explored the Val Visdende (the picture is the starting point in Mestre!). This probably closes the circle of possible sites for observation on the North East as the crow flies is only a few miles from the Piave sources. The Peralba seen eastward E 'at about 1300 meters above sea level, well protected by a ring of mountains is not very high along the northern arc. To the south is a free fork pointing right at azimuth 0 ° and allows you to see objects in meridian up to about 10 degrees above the horizon (up to about -35 ° declination).
The mountains protect it from wind and the temperature is milder. There was a few degrees below zero and the still air does not hurt (at the time the Three Peaks, there would be 12-15 degrees below zero, winds to 22 mph with gusts to 44 mph - according to weather data). The downside is the seeing that in the valley is not good if it is above the ridges surrounding the wind blows. In fact seeing the beginning did not allow to use more than 130x (otherwise not have star point). Over the course of the evening is a bit 'better. Sure, you can have pinpoint stars at 260X in the deep sky images is an advantage, but this only occurs regularly in the Three Peaks. The extraction fan boundary layer nevertheless worked well and there were no signs of the boundary layer to add damage to the image.
The access road is easier and seems to be open all year. So this is a good alternative to winter Casera Razzo. A little 'more distant from the plain, a little' less cold, a bit 'lower (resulting in higher extinction) and the South freer horizon.
There are hotels in Santo Stefano is open all year round. We were at Krissin: € 48 including dinner and breakfast (ask for Lara, there is no problem to return at night). In fact when we arrived at the hotel the sky was overcast, so we take the room without supper. When we arrived in Val
Visdende were no clouds in flashes but then, before midnight (as forecast meteo.it) was open. We placed in the widest part of the valley, just north of the church. Some houses were inhabited, but the lights were all gone, except for a lighthouse at the entrance of the valley (but it was a couple of miles before where we were and thus invisible). I'll have to report it because it violates the regional law against light pollution (plus you do not understand what it is used).
Although it was open, the sky was not perfectly clear, or perhaps it was only 1300 m above the extinction is higher than in 2300. The Milky Way was not opposed to the Tre Cime. The sack of coal of the North was always the blacker the sky, but it stood out in the same way. The SQM showed average values \u200b\u200baround a 21.49 (dopo mezzanotte) fino a circa 21.45 verso le due e mezza di notte. Rispetto al 21.55-21.60 delle Tre Cime, e complice anche la maggiore estinzione, la differenza si vedeva... starei per dire che c'era un "abisso". Anche al telescopio. Ho voluto controllare NGC6946, senza poter usare gli stessi ingrandimenti delle Tre Cime (questa volta circa 170-200x, mentre alle Tre Cime anche 260x). Questa la descrizione del 27 agosto : " Potevo vedere le spirali, e potevo anche intuire diversi nodi di stelle lungo le spirali. Non credo di averla mai vista così bene. Il nucleo era cosa a sé: più luminoso e fine. Infine si poteva percepire l'intero alone debole della galassia ". Questa volta invece dell'alone esterno there was no sign and there were only two good arms. Nodes even the shadow of stars ... Definitely, Maybe if I had a special refractor I would see even better live Three Peaks ... but I was only a Dobsonian 400, with extraction of the boundary layer and optical lambda/8-9 by Zen (interferometric test). Mv
The limit was about 6.5-6.6 (the Three Peaks 6.8-6.9). M33 was visible easily distracted, at times almost in direct and had a clear appearance nebulare.Era but very high in the sky.
Light pollution filters from throughout the South By South West may come from Santo Stefano di Cadore. The clouds above the valley were black, with the exception of those that leaned toward Santo Stefano, illuminate dal basso. In ogni caso, sparite le velature, l'orizzonte Sud non era poi molto più luminoso di quello Nord (ad una osservazione non attenta poteva passare inosservato, non a me e a Mar4ever il namibiano ).
Anche dalla forcella Sud filtrava luce. Eppure a Sud c'è solo il monte Terza Grande, più in là c'è Casera Razzo e poi altre montagne fino alla pianura, fra i 60 e 110 km di distanza. Probabilmente stavamo osservando la luce della pianura, un po' come dalle Tre Cime .
Lungo l'orizzonte Nord c'era un po' di luce, che a giudicare dal colore uscito nelle fotografie (verde) era probabilmente l'airglow.
Marco ha scorto per primo il Gegenshein nei Fish. The high position in the sky and the distance from the Milky Way (this is the best time, as well as when it is in Cancer) has allowed to see him from a sky of 21:45!
When disassembled, the telescope was covered by a thick layer of frost. It 'was then that we realized that the refractor would be even higher really deep sky , except that maybe some jewels are not taken willingly to take the ice.
Some items observed.
NGC 246 in Cetus. A beautiful planetary nebula showing different light and dark some stars in it. I dare not think how it could appear in that 155 mm showing the central of M57.
NGC 210 in Cetus . It was noticeable at the core, the bar and spirals. Picture a little 'affected by light pollution in the South appeared smaller than the picture in the link, but the star was visible on the spiral (also served here might be another refractor, you know ... "is not sensitive to' light pollution ").
NGC 7380 in Cepheus.
NGC 7822 in Cepheus .
NGC 1360, in Furnace . It 's a very large planetary nebula is interesting because, with the OIII filter shows three darker spots inside (a little' as the Owl).
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