The power of Tycho's image was not limited to Europe. In about 1670 the Flemish Jesuit missionary in China, Ferdinand Verbiest, was given charge of the Imperial Observatory in Beijing and set about re-equipping it with a new set of instruments. He chose Tycho as his model and the Mechanica as his text, building an observatory on the Tychonic model.

The Museum has a rare original set of illustrations detailing the form and construction of the instruments for the Beijing observatory, printed in China around 1674 on a total of one hundred and five separate sheets of paper approximately 390 x 460mm in size.

Here are instruments from Uraniborg - such as the altazimuth quadrant, the bipartite arc and the great celestial globe - refashioned in China, modelled directly on the Tychonic precedent but with eastern decoration. The sights are of Tycho's design and the arcs are divided by transversals as he had done.

Most surprising of all is that Verbiest has built two armillary spheres, instruments tried but condemned by Tycho and not attempted by Hevelius. There is even a zodiacal armillary - the most complex and impractical of instruments for measurement, originally described in Ptolemy's Almagest.

The Jesuits were using European astronomy to persuade the Chinese of the superiority of the Christian tradition that had produced it, so why choose to present them with an astronomical technology a century old and obsolete in the West? One proposed explanation is that it was the best that could be handled with the available labour and materials.

Another explanation could be that the Jesuits were more comfortable in a Tychonic astronomical tradition, since it adhered to a stationary earth and eschewed the heretical hypothesis of Copernicus. But part of the answer may lie in the continuing rhetorical power of Tycho's instruments, evoked most tellingly by the majestic geometry of a large armillary sphere. As was the case when Tycho dedicated his Mechanica to Rudolph, the noble Dane's Heavenly Castle still offered the most appropriate model for the Emperor's observatory.