Doscovering of Neptun: Britain Cheated the French

Revealed: how Britain put the spin on Neptune

Long-hidden documents expose how the 19th-century scientific elite cheated the French to win credit for discovering the planet.

Robin McKie, science editor
Sunday December 12, 2004
The Observer

Britain has been found guilty of one of the strangest crimes in history: the theft of another world. A group of international historians has concluded that the UK authorities hijacked credit for the discovery of the planet Neptune, robbing French astronomers of the sole glory they deserved for the achievement.
This verdict is the outcome of years of detective work by the group and only became possible with the finding in Chile of a sheaf of crucial documents that had been stolen from the Royal Greenwich Observatory. These, and other contemporary papers, show Britain indulged in its own 19th century attempts at spin doctoring to support its claim that the UK mathematician John Crouch Adams had predicted the existence of Neptune.

He hadn't, say William Sheehan, Nicholas Killerstrom and Craig Waff in the latest issue of Scientific American . 'The Brits stole Neptune,' they conclude with uncompromising certainty. In other words, it was just another dirty trick by perfidious Albion.

The battle over Neptune had its roots in the discovery, in 1781, of a new member of the solar system - Uranus, the Sun's seventh planet. The observation, made in England by William Herschel, stunned both scientists and the public, who had no idea the Sun's family possessed an unseen world.

But Uranus proved to be a problem. Astronomers kept finding it in the wrong parts of the heavens. Was another even more remote mysterious world pulling Uranus out of its orbit, they wondered?

The French mathematician Urbain Le Verrier decided the answer was yes, did some calculations and told astronomers in Berlin exactly where to point their telescopes. On the night of 23 September 1846, after only half an hour's observation, they spotted a small blue disc exactly where Le Verrier had predicted. The discovery - of Neptune - was hailed as a triumph for French science.

Then the Brits stepped in. Yes, the French had done jolly well, but actually we had already worked out where the planet could be found. It's just that we hadn't got round to pointing our telescopes at the right bit of the sky.

And as proof, the Astronomer Royal, Sir George Biddell Airy, presented a set of documents in which he outlined Britain's case. These included papers that were supposed to show details of Adams's calculations and predictions.

In the end, it was decided Britain and France should share the glory and that Adams, a strange, reclusive but undeniably brilliant mathematician, and Le Verrier should be rated as Neptune's joint discoverers.

Yet Britain's claim always rankled among astronomers, and by the 20th century, historians decided to launch a detailed investigation of the documents that were supposed to back Airy's claim.

'But whenever they requested the file [of documents] from the Royal Greenwich Observatory, librarians stated it was "unavailable",' the trio write in Scientific American .

In fact, the file had been stolen by an astronomer called Olin Eggen and only with his death, in Chile six years ago, did the hunt for the file end, they add. 'This fortunate discovery, as well as the discovery of relevant documents in other archives, has allowed us to re-examine Neptune's discovery.'

And their conclusions? Britain's astronomers grossly exaggerated Adams's contribution. Adams was a shy, sober, fastidious, religious man, most probably suffered from Asperger's syndrome, and was the most venerated mathematician of his day. His colleagues gave him strong, but largely undeserved backing, while the French failed to support Le Verrier, who was unpopular with his colleagues.

Yes, Adams worked out where Neptune might be found but clearly didn't bother to try to convince anyone else that he was on to a winner. His only attempt to get the interest of Airy, the most important astronomer in the land, occurred on 21 October 1845, when he called, unannounced, at the latter's lavish residence on Greenwich Hill. Adams presented his card, but Airy - who is generally depicted as a bumptious bureaucrat - would not see him.

Only later, when the shock of the French discovery began to sink in, did Airy try to rectify the situation, and claim that the young mathematician was poised to pinpoint the planet. Adams did some interesting calculations but not much more.

'The credit belongs only to the person who succeeded both in predicting the planet's place and in convincing astronomers to search for it,' say the authors. 'The achievement was Le Verrier's alone.'

In other words, the international decision that Britain should share in the glory of Neptune's discovery was based solely on that great British gift to civilisation: a sexed-up dossier.

Neptune discovered

Neptune orbits the Sun at a distance of 4.5 billion kilometres (2.8bn miles) and is the solar system's second most remote planet.

The strongest winds in the solar system have been recorded on Neptune, at speeds of up to 2,000km per hour.

Since its discovery in 1846, Neptune has not yet completed a full orbit. It takes 165 years for the planet to go around the Sun.

The coldest temperatures measured in the solar system (-230C) have been recorded on Neptune's moon, Triton.

French politicians wanted to call the planet Le Verrier after its discoverer, but this plan was vetoed by other countries.