Starry Starry Night

One stereotypical character of the Victorian Age is the “gentleman scientist”, men (and they were, with the exception of Lady Ada Lovelace, all men) with the financial wherewithal to putter around in their scientific pursuits without the need to actually work for a living.  Charles Darwin, Humphrey Davy, and Benjamin Franklin were all men of independent means and scientific interests.

Another was William Parsons.  Although less famous than the examples above, William Parsons was fortunate enough to inherit an earldom and a large estate in Ireland upon his father’s death. Now as the 3rd Earl of Rosse, he was free to concentrate on his astronomical pursuits.

Although Ireland may seem to have disadvantages as the site of an astronomical observatory—cloudy skies, moisture, and an elevation close to sea level come to mind—he had plenty of land there and plenty of money. So Lord Rosse started building increasingly larger telescopes at Birr Castle culminating in 1845 in a massive instrument with a 72-inch diameter mirror dubbed “The Leviathan of Parsonstown”. It was unlike any previous telescope, requiring massive machinery to move.  It wasn’t until 1918 when the 100-inch Mount Wilson telescope in California was built that a larger telescope was achieved.

The Leviathan of Parsonstown

Lord Rosse’s special interest was solving the nebula problem. Nebulae were faint fuzzy objects in the sky. One group of astronomers believed that they were gas clouds, while the opposition thought them clusters of stars which only appeared fuzzy when observed through telescopes of insufficient size.

And there was no telescope of more sufficient size than the Leviathan.  Observations were made.  Some nebulae were resolved into clusters of stars by the Leviathan’s colossal eye.  Others remained stubbornly fuzzy.  The issue was not resolved. (In fact, those objects in the sky called nebulae are two different things:  gas clouds, and galaxies filled with stars, but that wasn’t determined until even larger telescopes with cameras attached were developed.

And that last point is important.  When the Leviathan was built, photography was in its infancy, and astronomical photography even more so. Observations were recorded by making hand-drawn sketches. One of Lord Rosse’s most famous sketches was of the nebula numbered M-51 which he made in 1845. Lord Rosse drew a nebula with spiral arms and a second smaller nebula interacting with it.  The sketch was so much clearer than what had ever been seen before that it was widely reproduced and published in many popular astronomy books of the day throughout Europe.

Drawing by Lord Rosse of nebula M-51 (now called the Whirlpool Galaxy) through the 72-in Leviathan telescope.
The Starry Night, by Vincent van Gogh, 1889

It does not take much imagination to recognize that Lord Rosse’s sketch of what we now know as the Whirlpool Galaxy greatly resembles the stellar swirls and eddies of Vincent van Gogh’s immortal painting “Starry Night”  Do we know for certain that van Gogh had seen Lord Ross’s sketch? No. Perhaps he did. Or perhaps his artistic vision could tap into the scientific discoveries being made during that time. The two men weren’t contemporaries—“Starry Night” was painted in 1889, forty-four years after Lord Rosse’s sketch—but the sketch was well known.

Perhaps, Lord Rosse and van Gogh approached the same subject from two different vantage points—science and art.  While “Starry Night” is now fixed for all time, progress on astronomical instruments and the observations they are able to make have continued.  Below is a photograph of the Whirlpool Galaxy taken by the Hubble Telescope.  While the abstract billows and curls of Lord Rosse’s sketch appear to us different than they did in 1845, the majesty of the this immense galaxy still provokes awe, just as van Gogh’s does.

M-51, the Whirlpool Galaxy, taken by the Hubble Space Telescope

Voyages of Heavenly Discovery: Eclipse Expeditions

The upcoming total solar eclipse prompted me to look into the grand history of scientific expeditions, specifically expeditions to observe rare astronomical events.


Captain Cook’s observatory on Tahiti. Note the carefully mounted long-case clock.

One of the first voyages of discovery was to the newly discovered island of Tahiti (well, at least new to Europeans, the Tahitians obviously already knew it existed) on a ship called HMS Endeavour captained by a young Royal Navy Lieutenant by the name of James Cook.  The purpose of the voyage (at least publicly…) was to observe the Transit of Venus of 1769, that is, to watch and accurately time the planet Venus crossing in front of the sun. The ship’s company also included Joseph Banks, the famed botanist who brought along with him several assistants, two artists, and two servants.  Charles Green was appointed by the Royal Society to by one of the ship’s astronomers, the other being Cook himself who was a skilled observer.

And why all this expense to travel to the other side of the globe to observe one arcane astronomical event? The public reason was to improve navigation, specifically determination of longitude.  While the latitude of a ship at sea was easily determined with a sextant and a sunny noon-time, longitude was more difficult.  By comparing the times of the Transit of Venus at various places across the globe–some of whose positions were already accurately known, the longitudes of the observing sites could be determined with greater precision. (The longitude problem was eventually solved by John Harrison and his marine chronometers.)

So the Endeavour reached Tahiti, they timed the Transit, and then Cook opened his second set of sealed orders which essentially said, “Go look for this Terra Australis we keep hearing about, and if you find it, claim it for Britain.” After completely mapping the coast of New Zealand, Cook sailed a bit further west and found Australia.

Later astronomical expeditions were somewhat less imperialistic.

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