British astronomer eclipsed by Galileo’s telescope

Today marks the high point of the International Year of Astronomy: 400 years ago, on August 25 1609, the great astronomer Galileo Galilei demonstrated what would later be called a 'telescope' to Venetian bigwigs at the court of the Doge Leonardo Donato.

In the following months, Galileo was credited with being the first man to use the new invention to observe the heavens. But British astronomers should be shouting the truth from the rooftops: this last accolade is undeserved.

The refracting telescope that Galileo showed off to the Venetian leader was a refinement of a Dutch invention that had been around for at least a year. The 'Dutch trunke' had a magnification power of about 3x and produced an upside-down image, whereas Galileo's new design could achieve a magnification of 8x, and importantly rendered an upright image. The gadget proved lucrative for Galileo who found keen buyers in merchants and seamen.

However it was when Galileo turned his telescope to the heavens that he started along a track that would see him hailed as the 'father of science'. Over the following years, he made observations such as the discovery of Jupiter's moons and Venus's moon-like phases - which culminated in his support for the heretical Copernican view that the sun, rather than the earth, was at the centre of the universe.

But on July 26, 1609 - a full month before Galileo's demonstration to the Venetian court - a British astronomer, Thomas Harriot (above), turned his own Dutch trunke to the moon and drew what he saw.

His first crude drawing, followed later by more detailed maps, depicted the 'seas' of the moon, including the Mare Crisium and the Mare Tranquilitatis. It would be six months before Galileo finally got round to recording his own observations of three of Jupiter's moons.

Unlike the self-publicising Galileo, the Richard Dawkins of his day, Harriot never published his maps or observations and died uncelebrated in 1621. ·