Essential Information

Royal Observatory

14 Apr 2015

In this new Insight Astronomy Photographer of the Year-inspired blog post about astronomically-themed objects from the Museum’s collections, I am looking at planets and other cosmic bodies in our solar system.

Celestial globes, armillary spheres and orreries are not only useful astronomical tools; they can also be objects of astounding aesthetic satisfaction. Artfully designed, they often show ingenuity as well as technical skill.  There are a number of remarkable orreries in the collection, but my favourite is one that is said to have belonged to Margaret Maskelyne, daughter of the fifth Astronomer Royal, Nevil Maskelyne. It’s not only a thing of beauty: I find the idea of a little girl partaking in her father’s intellectual pursuits quite touching.

Margaret Maskelyne's Orrery, by William Jones, ZBA4664.


  An orrery is a mechanical model designed to illustrate or predict the motions of the planets (named as such by the Greeks because planetes means ‘wanderer’) and satellites in our solar system.   Margaret’s orrery dates from the early 19th century, but these were invented in the previous century.  The detailed representation of a ‘grand orrery’ below was published in the wonderfully titled Universal Magazine of Knowledge and Pleasure, which was typical of the Enlightenment, a period of great scientific enquiry and intellectual curiosity.

The Orrery, engraving by John Hinton, 1749, PAJ3468.


  A mezzotint after a famous painting  by Joseph Wright of Derby, 'A Philosopher giving that Lecture on the Orrery in which a lamp is put in place of the Sun’, shows how the instrument was used.

A Philosopher Giving a Lecture on the Orrery, mezzotint after a painting by Joseph Wright of Derby, 1768, PAJ3149.


  Several of Wright of Derby’s paintings are based on the meetings of the Lunar Society of Birmingham, a group of scientists and pioneering industrialists from the Midlands who met once a month, during the full moon, to discuss topics of intellectual interest. Here, the use of the mezzotint, a printmaking technique particularly suited to strong contrasts of darkness and light, allow to evoke the mystery and wonders of astronomy: artificial light gleams dramatically on the instrument and the audience’s astonished faces alike. The children huddled around the mechanical device show this was an object of fascination for all ages. As discussed in my previous blog entry, during the 19th century there was a drive to make astronomical science accessible to popular audiences, and educational depictions were circulated in various media.

Comparative Magnitudes of The Planets from Reynolds' Series of Astronomical Diagrams, AST0051.


  The comparative magnitude of the planets and their relative distance to the Sun, as well the phases of Saturn and Venus, are represented in this lithograph from James Reynolds’ series of astronomical prints. It shows the latest discoveries in astronomical sciences: first observed in 1846, the eighth planet in the solar system, Neptune, thus features. Equally informative, this wall hanging from the Working Men's Educational Union is also an example of attractive graphic design that seems decades ahead of the 1850s: in fact, it would not look out of place in a fashionable 1930s, or even 1960s, home.

Wall hanging showing the Solar System, Working Men's Educational Union, 1850-60, ZBA4550.


  It does not only illustrate the motion of the planets: one object is depicted racing through space. Indeed, Halley’s comet is one of those cosmic bodies that have captured people’s imagination for centuries. The weathervane on top of the Royal Observatory’s Altazimuth pavilion reproduces one of the earliest known depictions of this comet, from the Bayeux’s Tapestry, which commemorates the events leading to the Norman conquest of England in 1066.

View of the dome of the Altazimuth pavilion.


  Comets (from kometes, ‘long-haired’ in Greek), are also known as ‘blazing swords’ or ‘bearded stars’. In this other print from Reynolds’ series, comets are described as: ‘light vapoury bodies, generally consisting of a splendid, but ill defined cloudy mass of light called the head, from which a long stream of light called the tail diverges’.

Comets and Aerolites, from Reynolds' Series of Astronomical Diagrams, AST0051.


  In fact, comets consist of a nucleus of ice and dust, the ‘tails’ being caused by ice melting away as they approach the Sun. The same print depicts so-called ‘aerolites’, which are a form of meteor. At the bottom of the page are two picturesque depictions of showers of meteorites, a subject now popular with amateur astrophotographers. It seems that, in some instances, the designs for the Working Men's Educational Union’s hangings were directly based on Reynolds’ series. Indeed, this hanging reproduces closely several designs of the print above, including the six-tailed comet of 1741.

Wall hanging showing Comets, Working Men's Educational Union, 1850-60, ZBA4553.


  In both print and hanging, some of the comets have an almost animal feel to them, and resemble sea creatures. Similarities in the ways the sea and space are visualized and described are not uncommon, as the exploration of the confines of the universe can be compared to that of the depths of the ocean. Until Isaac Newton and Edmond Halley revealed that they had predictable ellipses and could be periodic, comets were often seen as a bad omens. Once a periodic comet was identified, however, they became objects to look forward to seeing in the sky. Poignantly, while Halley had determined that the comet that was to bear his name was visible from Earth every 75-6 years, he did not live to see it grace the skies in 1759. Some of us may be lucky to observe its return in 2061, but other comets’ recurrences are even rarer, due to their long elliptical orbit. The first and only recorded apparition of Donati’s Comet, in 1858, was one of the most impressive astronomical events of the 19th century: the beauty of the comet, which had an extraordinarily long tail, mesmerized scientists, artists and public in equal measure.

Wall hanging showing Comets, Working Men's Educational Union, 1850-60, ZBA4554.


  Its claims to fame include featuring in William Dyce’s Pegwell Bay, and being the first comet ever photographed, by English artist William Usherwood, followed closely by American astronomer George Phillips Bond – certainly inspirational figures for 21st-century amateur astrophotographers.