The Hammock Papers: M41

11 January 2010

M41

Discovered by Giovanni Batista Hodierna before 1654. Perhaps known to Aristotle about 325 B.C.

Open star cluster Messier 41 (M41, NGC 2287) is lying about 4 degrees nearly exactly south of Sirius, the brightest star in the sky. It contains about 100 stars, including several red (or orange) giants, the brightest being of spectral type K3 and mag 6.9, and situated near the cluster's center. This star is about 700 times more luminous than our Sun. The stars are distributed over a volume about 25 or 26 light years across, and all receding from us at 34 km/sec. As they are at a distance of 2,300 light years, they appear scattered over an area of 38 arc minutes diameter.

The age of M41 was estimated at 190 million years (Sky Catalog 2000) and 240 million years (G. Meynet's Geneva Team). The hottest star has been found to be of spectral type A0. All sources agree that it is to be typized as of Trumpler class I,3,r. This stellar swarm is receding from us at 34 km/sec.

Helfer, Wallerstein, and Greenstein have investigated M41's K-type red giant stars, and found their chemical composition very similar to that of our sun.

J.E. Gore mentions that M41 was "possibly" recorded by Aristotle about 325 B.C.; this would make it the "faintest object recorded in classical antiquity" (from Burnham). However, this identification is uncertain: A.A. Barnett presumes that Aristotle may have described the Milky Way near the star d CMa.

Hodierna was the first to catalog it before 1654, and it got generally known after John Flamsteed's independent rediscovery of February 16, 1702, who remarks (No. 965 in his catalog): "Near this star (12 CMa), there is a cluster." It was independently found again by Le Gentil in 1749, and apparently by Charles Messier, who added it to his catalog on January 16, 1765.

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WOLFGANG AMADEUS MOZART

"When I am, as it were, completely myself, entirely alone and of good cheer – say travelling in a carriage or walking after a good meal, or during the night when I cannot sleep – it is on such occasions that my ideas flow best and most abundantly. Whence, and how, they come I know not ; nor can I force them. Those ideas that please me I retain in memory and am accustomed, as I have been told, to hum them to myself. If I continue in this way, it soon occurs to me how I may turn this dainty morsel to account, so as to make a good dish of it. That is to say, agreeable to the rules of counterpoint, to the peculiarities of various instruments etc. All this fires my soul, and, provided I am not disturbed, my subject enlarges itself, becomes methodised, and defined, and the whole, though it be long, stands almost complete and finished in my mind, so that I can survey it like a fine picture or a beautiful statue at a glance. Nor do I hear in my imagination the parts successively, but I hear them, as it were, all at once. What a delight this is, I cannot tell."

MARCUS AURELIUS

"Is your cucumber bitter? Throw it away. Are there briars in your path? Turn aside. That is enough. Do not go on and say, 'Why were things of this sort ever brought into this world?' neither intolerable nor everlasting - if thou bearest in mind that it has its limits, and if thou addest nothing to it in imagination. Pain is either an evil to the body (then let the body say what it thinks of it!)-or to the soul. But it is in the power of the soul to maintain its own serenity and tranquility."

VINCENT van GOGH

"What am I in the eyes of most people? A nonentity or an oddity or a disagreeable person — someone who has and will have no position in society, in short a little lower than the lowest. Very well — assuming that everything is indeed like that, then through my work I’d like to show what there is in the heart of such an oddity, such a nobody. This is my ambition, which is based less on resentment than on love in spite of everything, based more on a feeling of serenity than on passion. Even though I’m often in a mess, inside me there’s still a calm, pure harmony and music. In the poorest little house, in the filthiest corner, I see paintings or drawings. And my mind turns in that direction as if with an irresistible urge. As time passes, other things are increasingly excluded, and the more they are the faster my eyes see the picturesque. Art demands persistent work, work in spite of everything, and unceasing observation."

DAN CAMPBELL