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Prior to the dawning of the photographic era, astute and careful observers produced some of the most exquisite drawings of objects in our night sky, by eye and by hand. One of our favorite drawings of the Milky Way Galaxy comes from the work of the French born artist and amateur astronomer Etienne Leopold Trouvelot (1827-1895), who emigrated from France to the United States in 1855. In 1882, Trouvelot clearly stated his intentions in a volume entitled The Trouvelot Astronomical Drawing Manual:

My intent is ... to represent the celestial phenomena as they appear to the trained eye and to an experienced draughtsman through the great modern telescopes provided with the most delicate appliances ... my aim is to combine ... accuracy in details ... with the natural elegance and delicate outlines peculiar to the objects depicted ... A well-trained eye alone is capable of seizing the delicate details of structure ... which are liable to be affected, and even rendered invisible, by the slightest changes in our atmosphere.

He was captivated by the grandeur of the Milky Way (Figure 24), and wrote:

During clear nights when the Moon is below the horizon, the starry vault is greatly adorned by an immense belt of soft white light, spanning the heavens from one point of the horizon to the opposite point, and girdling the celestial sphere in its delicate folds.

Trouvelot's drawing of the Milky Way was based on naked-eye studies spanning not one month, or four months, but the years 1874-1876. Discernable are stars belonging to the constellations of Scorpio, Sagittarius, Aquila, Lyra, Cygnus and Cassiopeia ... also magnificently captured, with his astute eye, are the "starry vaults" in our Galaxy. The Milky Way truly spawns multitudes of Shrouds of the Night in Trouvelot's exquisite drawing.

What an extraordinary challenge it must have been to produce drawings of the night sky - by hand: one obviously would require some faint light source (such as a candle) to carefully guide the hand on paper in the drawing process, but the pupil of the eye immediately contracts upon looking at candlelight, and more time is then needed to get the eyes "dark-adapted"

again, before undertaking further drawings of the night sky. Positional accuracy was essential. Furthermore, darkness (the absence of a bright Moon) is crucial to visually appraising the grandeur of the Milky Way, as Trouvelot himself pointed out.

Trouvelot produced approximately seven thousand astronomical drawings (examples appear in Figures 25-29), including the planet Saturn (Figure 25), a star cluster in the constellation of Hercules (Figure 26), the Great Nebula in Orion (Figure 27, based on telescopic observations in 1875 and 1876), a total eclipse of the Sun (July 29, 1878), exquisite lunar landscapes, the Aurora Borealis (March 1, 1872), the Great Comet of 1881 (Comet Tebbutt) and the splendor of the zodiacal light (Figure 28). The glowing zodiacal light is due to sunlight scattered off particles of cosmic dust which are present in our solar system. This interplanetary dust is distributed in a volume of space centered on the Sun and extending beyond the orbit of our Earth. Also drawn by this assiduous observer were "The November Meteors" (see Figure 29). Trouvelot vividly recalls the extraordinary celestial display on November 13, 1868:

My observations were begun a little after midnight, and continued without interruption till sun-rise. Over three thousand meteors were observed during this interval of time ...

(italics, ours)

It is a fitting tribute to this exceptionally gifted artist that at coordinates 49 degrees north and 6 degrees east on the Moon, lies the Trouvelot crater, named in his honor.

A key discovery regarding the structure of galaxies outside of our Milky Way came from Ireland. A giant mirror, measuring 72 inches across, was successfully cast on April 13, 1842 and formed the heart of the famous "Leviathan of Parsonstown," a telescope which saw "first light" (a term used by astronomers to denote that moment when a fully assembled telescope receives its "first set" of celestial photons) on February 15, 1845. The "Leviathan of Parsonstown" is still in place today at Birr Castle in Ireland. At the time, it was the largest reflecting telescope on the planet. William Parsons, who became the 3rd Earl of Rosse From Seeds to Stars in 1841, visually identified spiral structure in the Whirlpool Galaxy Messier 51, in 1845. 53

Shrouds of the Night

58 Figure 29 [408]

Lord Rosse subsequently identified spiral structure in approximately 20 additional galaxies. Exquisite drawings were made at the telescope; among the galaxies drawn were Messier 101 (Figure 30) and Messier 33 (Figure 31), as well as the Dumbbell Nebula within our Galaxy (Figure 32).

Astronomers at Birr Castle included R.S. Ball (who worked there in the period 1865-1867) as well as J.L.E. Dreyer (1874-1878), who became world famous for his "New General Catalogue" (N.G.C.) of celestial objects.

The telescope was dismantled in 1908 but was restored in the period 1994-1999; tourists to Ireland should not miss a visit to see this historic telescope through which the spiral pin-wheels in the Whirlpool Galaxy were first detected. An exquisite drawing of the Milky Way was produced at Birr Castle by the German astronomer Otto Boeddicker (1853-1937), who became the astronomical assistant to Lawrence Parsons, the 4th Earl of Rosse. Boeddicker's breathtaking drawings of the Milky Way (Figures 33 and 34) were made over a period of six years, and published in 1892.

Boeddicker wrote:

The drawing of the Milky Way referred to was begun by me on October 24, 1884, and has occupied the greater part of my time and energy ever since. It was undertaken in the belief than an accurate representation of the Galaxy, such as it appears to the naked eye, was an astronomical desideratum, and would be of some value for a variety of special investigations ... As much as possible I drew the different sections only when they were near the meridian, in order to obtain the conditions most favourable for atmospheric transparency. This involved for the greater part of the Milky Way the necessity of my lying flat on my back (or nearly so) in the open air for hours together - a position which, especially on frosty nights, proved somewhat trying, for no amount of clothing was found sufficient to counteract the radiation of heat from the body ...

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