It was a breathtaking sight. Two Falcon Heavy boosters performed a synchronised vertical landing and, minutes later, another indelible image entered the world’s imagination. A bright red sports car orbited the Earth. The man responsible, SpaceX’s Elon Musk, received widespread acclaim for launching the largest rocket since Apollo’s Saturn V. The car divided opinion.

It was either a cheerleader for space science, a marketing masterpiece or, as the mannequin astronaut enjoyed planetary selfies, another potentially dangerous temporary piece of space junk.

There are over half a million pieces of debris that are not much larger than a marble, littering the Earth’s orbit and over 20,000 the size of a cricket ball or larger. These bigger pieces range from an astronaut’s glove to dead spacecraft and disused rocket stages. Yet size does not always equate to the greatest danger.

As we enter a new space race, with more nations like China and India joining the quest to explore the cosmos, we will be adding more and more of this flotsam into orbit. The next generation of space scientists face a big challenge: how to ensure our future wave of spacecraft survive this ever-increasing belt of rubbish.