For as this seemingly pristine blue planet makes its serene journey around our life-giving Sun, it does so covered by a cloud of space junk.
According to Nasa, there are more than 100 million pieces of metal and other detritus of at least a millimetre long, including thousands bigger than a tennis ball.
Given they are travelling at speeds of up to 17,500mph, all this garbage poses a real threat to working satellites, spacecraft, and indeed, astronauts.
Most of it was caused by accident. For example, in 2009, a broken Russian spacecraft bumped into a functioning American one, destroying it, in a collision that created thousands of pieces of debris. However China’s decision to test fire a missile at an old satellite in 2007 was a deliberate act that contributed thousands more.
So the first impressions of humanity formed by those intelligent aliens, if they exist, may well be that we are a particularly untidy species with little consideration for the environment in which we live.
Given how recently we started sending machines and people into space, it is remarkable that we have managed to make quite such a monumental mess of it and done so little about cleaning it up.
Our alien observers may also have noticed the sharp rise in carbon dioxide in our planet’s atmosphere, the increasing global temperature, and the steady accumulation of vast amounts of extra energy from the Sun.
This may lead them to the conclusion that we are reasonably intelligent and extraordinarily industrious, but too busy and lacking in wisdom to realise we are sowing the seeds of our own destruction by fundamentally altering the climate that has enabled us to prosper as a species.
So calls by academics for special legal protections to be given to space – perhaps a global park in the sky, rather than a national park on land – might not only help solve an increasing problem for the burgeoning space industry, but also demonstrate, for all the galaxy to see, that humanity is just about smart enough to understand that it cannot trash its home without serious consequences.