The heavens were humanity's common property for thousands of years. Priests and astronomers might predict or interpret the movements of the heavenly bodies, but anyone could see the sky. The only new objects to discover before the invention of the telescope were occasional comets and novae.

Then on March 13, 1781 a unique event occurred. For the first time in the history of humanity one person discovered a new planet in the Solar System family. It was a professional musician observing the sky from his back garden through a telescope of his own making. The person was William Herschel. The place was 19 New King Street, Bath, England.

With the assistance of his sister Caroline Lucretia, William did the first all-sky survey of nebulae and revolutionized the science of astronomy. Caroline herself was awarded the Gold Medal of the Royal Astronomical Society and discovered a number of comets, nebulae, star clusters and galaxies.

The house on New King Street is now the Herschel Museum of Astronomy. Visitors to Bath can see for themselves the place in which history was made. It was opened exactly two hundred years after the discovery of Uranus.

New King Street wasn't a fancy place for professionals, wealthy merchants and the genteel folk that came to Bath to “take the waters.” The houses were aimed at artisans and the owners of small businesses, who were still reasonably prosperous. After all, the houses are five storeys and some of the rooms would have been for servants.

The museum consists of the first three floors and the garden. There is no documentation about the Herschels' furniture and decoration, unless you count Caroline's diary lament about how every surface seemed to be covered with pieces for telescopes. So the furnishing was chosen to fit the period. Interestingly, the garden has also been planted in accordance with the period.

In addition to the furnishings, there are, amongst other things, pictures of the Herschels, some of their books and belongings, musical instruments of the kind William would have played and a replica of the telescope he used to discover Uranus.

But I think the gem is in the workshop basement just off the garden.

William Herschel had a very can-do attitude. Therefore when he wanted a very large telescope, he wasn't dismayed that the local foundries couldn't cast a big enough mirror for it. He just decided to make his own, turning the workshop into a temporary foundry.

But it wasn't one of his successes. The mold broke, depositing molten metal on the flagstone floor. The sudden extreme heat made the stone expand and shatter with bits flying in all directions. It was fortunate that no one was killed or injured.

Since, unusually, the basement hadn't been rebuilt or converted over the two centuries, the original floor is there. Visitors can see the damage done by this accident which Caroline described in her diary.

A recent addition to the museum is a small extension into the garden to provide a space for special exhibits. It's called the Caroline Lucretia Gallery. It's a good exhibition space, though I didn't feel that it enhanced the garden. I suppose it's something you get used to.

The first exhibition, from June 30 – December 11, 2011, is about the Great Comet of 1811. It's called “Omens and Inspirations”. Besides the fact that this is the bicentennial of the comet, it also echoes Caroline's own fame as a comet hunter.

A Great Comet is one that is not merely visible to the unaided eye, but particularly bright. The last one was Comet McNaught in 2007, though its glories were limited to southern hemisphere observers.

William's and Caroline's observations on the comet are on display, lent by the Royal Astronomical Society. So are John Herschel's observations and calculations regarding Comet Halley, which he saw from South Africa in 1835. John was William's son and he was one of England's greatest scientists.

Another interesting artifact is Caroline's visitors' book. Amongst the stream of famous visitors was Lord Byron whose comet experience found its way into his poem Manfred. In the poem comets are malign influences, and many people shared the view that comets meant misfortune.

However if a canny ancestor of yours had purchased a bottle or two of the “comet wine” Chateau d'Yquem 1811, to which you were the heir, you would be very fortunate. The exhibition says that it's worth £43,000 ($67,000). However after “Omens and Inspirations” opened in June 2011, a bottle sold for £75,000 ($117,000).

Cheers!

The website of the Herschel Museum of Astronomy is here.