addition to the solar eclipse, which we discussed yesterday, January 4 We also reserve the spectacle of a meteor shower of the most important of the year, Bootidi or Quadrantids .
Just the fact that the same day there is the eclipse of the Sun is good news for fans of these meteors groped observation: when there is a solar eclipse means that the moon is new, therefore its light does not disturb the vision for the entire duration of the night.
The point from where the meteors appear to originate, that the radiant is circumpolar for northern half of Italy, and falls briefly below the horizon in the evening for the southern regions. Instead, in the morning hours, gradually moves toward great heights, encouraging comments. This year, some estimates put the theoretical maximum of the fall of meteors at 2:10 local on January 4, and therefore favored Italy could get out. A clear sky and not disturbed by light, at that time will look like in the above map (obtained Stellarium ), in which I pointed out the position of the radiation with a circle in the north-east. The star Arcturus is sure to be a reference, but also the helm of the Big Dipper in the upper part of the map.
Other calculations put it at the moment of maximum, with the greatest chance, among the 22 of January 3 and 7 days 4. In any case, the peak usually has a very long duration, but is rather pronounced and visually we see a sharp rise in the number of meteors observed. The hourly rate of fall (ZHR) average stood at 120, but there were occasions when there were more than 60 meteors per hour, and others in which this number has more than tripled. It should be noted that in 2009 we observed a peak lasting about 14 hours, absolutely abnormal to what has been said before, who knows what the thing does not happen again in 2011.
were saying the radiant is located within the constellation of Bouvier (Bootes), but once he was placed in an asterism now extinct, the mural quadrant. Here's where it comes from the name of Quadrantids, used to a greater extent than Bootidi.
The swarm is active from December 28 to January 12 or so, but far from the maximum provided the opportunity to observe some meteor is very low. The rate of entry into the atmosphere for you Quadrantids hovers around 41 km / s, so not fast.
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