Four hundred years ago the renowned Italian scientist Galileo Galilei pointed a telescope to the heavens and became the first man ever to see the craters of the moon and, more significantly for our understanding of the universe, the planet Jupiter’s four brightest moons. If, as was abundantly clear to him, these moons rotated around Jupiter, then, surely, the answer to the peculiar motion of the planets around the sky was that they rotated around the sun in a similar way, and not round the earth. This conclusion led to Galileo’s famous dispute with the Church, but it set astronomy on its course and this is what we in Greenwich are now celebrating in the International Year of Astronomy.
The Royal Observatory at Greenwich is playing its part with various events and a competition. Little over sixty years after Galileo’s discoveries, Charles II founded the Royal Observatory, hoping to improve navigation, save lives at sea and foster trade. The astronomer and architect Sir Christopher Wren suggested the site and designed the building. Meanwhile, the first Royal ‘Astronomical Observator’ John Flamsteed saw his task simply as the production of as full and as accurate a map of the stars as the instruments of the day could produce – instruments, incidentally, that royal parsimony required him to provide from his own pocket. One thing leading to another, Flamsteed’s map gave Isaac Newton the basis on which he could calculate the motions of the planets with such accuracy as to enable him to produce his theory of gravity. So, Greenwich has much to celebrate.
Its new planetarium is in full swing, and there are visits to the great Twenty-Eight Inch Refractor, among the largest telescopes of its type, but now just a museum piece. There’s also a photography competition, open to amateurs. For this, you will need a decent telescope plus camera, and some knowledge of how to do things, so it’s not for everybody. You will also need clear, dark skies, and you will not find them here; the glare of the city’s lights makes sensible photography of heavenly objects all but impossible. That’s why the Royal Observatory abandoned Greenwich for scientific observation as long ago as 1948.
This does not mean that there’s nothing worth observing from our murky skies. Binoculars or a small telescope with a tenfold magnification, firmly mounted to avoid wobble, will readily show what Galileo saw. With a fairly modest eight-inch telescope
Anthony Quiney’s book “A Year In The Life of Greenwich Park” was published recently by Frances Lincoln.