A few loose hairs from Berenice

It isn’t too late to mention the Coma Berenicid meteors, even though the Astronomical Calendar lists them at December 16. They are “active” for much of December and possibly into January. But their activity consists of, at best, one or two or three faint meteors an hour, and they are seen only after midnight, so mentioning them is academic and I doubt you’ll go out and watch for them. I have to mention them because of my fondness for Berenice herself and her constellation (http://www.universalworkshop.com/BERE.htm).

The Coma Berenicids may be part of a slightly larger complex, along with the Leo Minorids whose central date we give as Dec. 20. In other words, Earth may pass through two sparse meteor streams (or the sparse fringes of two meteor streams) of which the first seem to come from the direction of Coma Berenices and the second, generally later and a little more abundant, from the direction of Leo Minor. Or they may be just strands in a stream following in the approximate orbit of a single (unknown) comet.

LeoMinorids

It’s interesting to look out at the evening sky and see where these areas are. Around 9 or 10, great Leo has come into view, as if climbing a stair toward a throne, his chest-star Regulus above the east point, his tail down at the horizon. Leo Minor, one of the 17th century’s invented constellations, is a few faint stars north of him. And Coma Berenices, where is it? It is still below the horizon, just under our arrow that says “rising.” Remember that in the story it was once the tuft on Leo’s tail.

Thus, the meteors radiating from Coma are earlier in that they may have started a few days earlier, but later in that they can’t be seen till after Coma rises about midnight. The Leo Minorids are later in that they start a few days later, but earlier in that they can be seen from about 10 PM onward. We can look at a slice of the sky, parallel to the ecliptic and about 20 degrees north of it, that at this time in the evening has not finished sliding up into view and from which these occasional bits of cometary dust are flying.

This is the sort of vague complex about which meteor scientists, who detected it by radio means in 1959, become gradually more precise through continued observations.

Among recent dismaying news is that Derna, the pleasant little Libyan seaport where I once lived and which in Berenice’s Hair is identified with the elusive place called Irasa, has been taken over by fanatics of the Islamic State.

Write a comment