Every year, the world’s space agencies and a growing number of private companies spend vast sums of money exploring space. Rockets are launched, robots are sent to distant planets, and plans are drawn up for missions that once belonged only to science fiction. To some, this represents humanity at its most ambitious and inspiring. To others, it is an extravagant waste of resources that could be better spent solving problems here on Earth. The debate over whether space exploration is worth the cost is unlikely to be settled soon.

Those who oppose heavy spending on space make a powerful argument. The world, they point out, faces enormous challenges: poverty, disease, hunger and climate change affect billions of people. The billions spent on sending a robot to Mars, they argue, could fund hospitals, schools and clean water for those who desperately need them. Why, they ask, should we look to the stars when so much suffering remains unaddressed on our own planet?

Supporters of space exploration respond that this is a false choice. The money spent on space is a tiny fraction of global spending, and cutting it would not automatically solve the world’s problems. Moreover, they argue that space research delivers enormous practical benefits. Technologies originally developed for space missions have led to countless everyday inventions, from satellite navigation and weather forecasting to advances in medicine and materials. Studying other planets also deepens our understanding of our own, including the climate that sustains us.

Beyond the practical arguments, some make a more philosophical case. Human beings, they suggest, have always been explorers, driven by curiosity to see what lies beyond the horizon. To stop exploring, in this view, would be to abandon something essential about who we are. Perhaps the wisest position acknowledges that both sides have a point. Space exploration should not come at the expense of urgent needs on Earth, but nor should our earthly problems be used as an excuse to abandon one of humanity’s greatest adventures.