The bonnie, broukit bairn

On the 20th of August 1977, Voyager II was launched to be followed on the 5th September by its twin, Voyager I. The reversed sequence of launches was due to the different trajectories of the two craft as they set off for the outer reaches of our solar system to explore the gas and ice worlds of Jupiter, Saturn, Uranus and Neptune, taking advantage of a once-in-175-years alignment of the planets The pictures they sent back were astounding.

I've just been watching again the Voyager programmes on the television and marvelling at the engineers' ability to guide a tiny probe with about as much computing power as a mobile phone, across billions of miles and decades of time and to receive back these spectacular images as well as all the scientific data.

The Voyagers have now gone beyond the heliosphere, beyond the influence of our sun and are travelling across the galaxy more than 20 billion miles away and will probably continue to do so even after our sun and its planets have ceased to exist.

In the years between then and now, we have had the Viking Landers on Mars, the red planet; the Mariner and Venera missions to Venus; Galileo and Cassini to Jupiter and Saturn again, all adding to our view of our solar system and its occupants.

Of all the images the most powerful, to my mind, is that of the "pale blue dot". As Voyager moved towards interstellar space, the cameras were turned round to look back over nearly 4 billion miles and there was this tiny speck.

This moved Carl Sagan to ask us "to preserve and cherish that pale blue dot, the only home we've ever known."

The news is of micro-plastics in the snows of Antarctic, of animal, insect and plant species disappearing into extinction, and of global warming and the ecological and social problems that will bring.

The great Scots poet, Hugh Macdiarmid, showed remarkable prescience when in 1925 he wrote The Bonnie Broukit Bairn.

 Broukit, in Auld Scots, means neglected, begrimed. In 1925, it was dirty with soot from coal. MacDiarmid couldn't have imagined the levels of pollution we are now seeing.

Mars is braw in cramassy*,

Venus in a green silk goun

The auld mune shak's her gowden** feathers

Their starry talk's a wheen o' blethers,

Nane for thee a thochty sparin'

Earth thou bonnie broukit bairn

*crimson ** golden

Perhaps now we will spare a thochty for the pale blue dot.