The reflecting telescope comes of age

Telescope to James Gregory's design, which he demonstrated to the Royal Society in 1674. But other attempts even those made by leading craftsmen in the fledgling optical instrument trade failed to deliver the goods. In the meantime, long-suffering astronomers were stuck with their ridiculous spindly refractors, for the names of Chester Moor Hall and John Dollond meant nothing in those days. Then, quite abruptly, the situation changed. The Royal Society's Journal Book for its meeting of 12...

Genius and skill

Richard Reeve, besides being an excellent craftsman, was also something of a trailblazer on the London optical scene. Whereas on the Continent there was a well-established tradition of academic scientists working with optical craftsmen Rheita had Wiesel, for example, and, in Paris, Cassini had the gifted Italian optician Giuseppe Campani that was not the case in Britain. However, Reeve had been quietly working with the leading scientists of the day since 1641, when he had attempted to make...

Quantum leap

It was his thirst for more light that led Herschel to build the telescope for which he is perhaps best remembered even though it was only partially successful. The 'Forty-foot' was a giant whose 12.2 m long tube housed a mirror no less than 48 inches (1.2 m) in diameter. This famous instrument, whose likeness still adorns the seal of the Royal Astronomical Society, was conceived soon after the Large Twenty-foot was completed. By the summer of 1785, Herschel had written to Sir Joseph Banks at...

Success and obscurity

In the events that followed, it is easy to lose sight of the villains and heroes of the piece and in any case, those roles are defined only indistinctly. But we are fortunate to have the near-contemporary account of another accomplished optician, a fair-minded man who managed to stay above the fray, even though his own personal circumstances threatened at a later stage to draw him deeply into the morass. This man was Jesse Ramsden (1735-1800), a Halifax-born cloth-worker who had moved to London...

The great southern telescope

The metal-mirrored telescope reached its bittersweet apotheosis in a project that involved almost everyone we met in the last chapter. It carried the reflecting telescope tanta-lisingly close to its twentieth-century form, but brought in its wake controversy and recrimination and eventually, in an extraordinary twist, high drama in our own time. It was the Victorian scientific world's continuing obsession with the nature and structure of nebulae that spawned this ambitious project. Astronomers...

The touch of genius

If history has been grudging in its treatment of Hans Lipper-hey, it has been positively gushing towards the other great name associated with the earliest days of the telescope. But that is not surprising. Galileo Galilei, a professor of mathematics in the University of Padua near Venice, was as remote from the seedy world of small-time spectacle-making as it was possible to get. And it was he who took the Dutchman's little gadget like a baton in a relay race and turned it into an engine of...

Legends and lenses

Three hundred years before Della Porta wrote Magia naturalis, another scientist who has been credited by some with knowledge of the telescope languished in prison on exactly this charge. Roger Bacon (c.1214-1294), Franciscan friar and Oxford scholar, wrote his own 'great work', Opus maius, sometime around 1267 as a result of a bungled approach to Pope Clement IV. He had written to the pontiff in 1266 suggesting that the Church should coordinate the production of a great encyclopaedia of...

Acknowledgements

His damn book nearly drove me mad.' So wrote the late Spike Milligan in the foreword to his first novel, and I know exactly how he felt. More to the point, Stargazer nearly drove my family mad, and it is to them I owe the biggest 'thank you'. Without the unflagging support of Trish, James, Will and (by remote control from Scotland) Helen and Anna, the task would have been impossible. It would also have been impossible without the enthusiastic assistance of Sandra Ricketts, librarian of the...

Monsters with metal mirrors

Sir James South's choice of Dublin University to receive his precious Cauchoix lens in 1863 was no idle whim. The middle decades of the nineteenth century had seen Ireland emerge as a major force in astronomy, thanks to a group of innovative pioneers who had seized any and every available opportunity. It was no accident, therefore, that by then the world's largest telescope lay within Ireland's green pastures. The glue that held together this enterprising network of astronomers came in the form...

Better ways to make a telescope

The world of Islam has had a pretty bad press in recent years. From fatwa to jihad, from al-Qaeda to Jemaah Islamiah, the media have focused largely on the fanatics and the terrorists. They have paid little more than lip-service to the fact that one-fifth of the world's population lives by this ancient faith in a spirit of peace and harmony, and that Islam was once the single most civilising influence on a troubled world. A thousand years ago, Islamic culture produced some of the most able...

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100 inch mirror, 100 tonne telescope. The Hooker Telescope at Mount Wilson has been a favourite with astronomers since its completion in 1917. Like the 60 inch, the Hooker Telescope had a primary mirror focal-ratio of about f 5. This was somewhat slower than Ritchey's earlier 23.5 inch telescope probably because he was aware of the difficulties in making fast mirror surfaces in larger sizes. Nevertheless, it was fast enough to reveal details in photographs of spiral nebulae, and it was with...

The theory completed

Thus was the long-sought reflecting telescope brought to reality six decades after its refracting counterpart. Was Newton the inventor Or was it Descartes Or Mersenne Or Gregory Newton's great achievement undoubtedly lay in his refinement of optical surfacing technology, but he also approached the design of the instrument with insight and originality. He is, indeed, recognised today as the 'father of the reflecting telescope'. But as we have seen, that epithet has many caveats. Early in 1672,...

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The entry in the States General's Minute Book recording Hans Lipperhey's patent application for his telescope, 2 October 1608. General at the Binnenhof. He put his cards on the table, asking them to grant him a patent for 30 years during which time no one else would be permitted to make telescopes. Failing that, he would be happy with a yearly pension in return for which he would make telescopes solely for the State. The neat, measured handwriting of the duty clerk records for posterity the...

Mixed fortunes for the telescope

By the turn of the nineteenth century, on the eve of its 200th birthday the telescope seemed assured of a bright future. The thorny problem of chromatic aberration in refracting telescopes had been solved albeit amidst a flurry of acrimonious legal wrangling and long, spindly refractors yielding images fringed with spurious colour were now a thing of the past. The reflecting telescope, too, had progressed by leaps and bounds. While there were those who felt that William Herschel had overreached...

On the factory floor

Perhaps more important than the BTA in defining the archetypal telescope of the late twentieth century was a clutch of instruments in the so-called 4-metre class, built during the 1970s and early 1980s. No doubt their introduction also hastened the eradication of the old Imperial units from the vocabulary of telescope-building. There were eight of them, with apertures ranging from 3.5 m to 4.2 m. They were sited in both hemispheres (five in the north and three in the south), and they imparted...

The telescope in court

At the turn of the eighteenth century, there were few places in England more unspeakably dreadful than London's Newgate Prison. It is hard for us, as would-be time-travellers from the twenty-first century, to imagine anything like the squalor and violence that held sway behind its grim walls. Though it had been rebuilt after the Great Fire of London in September 1666, nothing about it could be described as enlightened and there was precious little in the way of comfort for its inmates....

Prelude to the telescope

It hardly bears thinking about, even today. Among all the dramas that have peppered the history of astronomy, few are more absurd than the after-dinner events at the home of a German professor of theology on 29 December 1566. Two hot-headed young men a long way from home, fanning a dispute that had been smouldering between them for days tempers flared swords were drawn. Their noble upbringing had trained them both well in the use of their weapons, and the impromptu duel they fought was swift...