This World Day of Social Justice, it's worth remembering that while the struggle for equity is ancient, our capacity to advance it has accelerated dramatically, powered by technologies that have expanded what philosopher Peter Singer calls "the expanding circle" of moral consideration.

Imagine the Earth with a twin. Not a sci-fi planet in another galaxy, but a digital double built with satellites, sensors, and supercomputers. This twin could simulate floods before they happen, test how cities handle heatwaves, and reveal the carbon cost of our infrastructure.That is the promise of a digital twin of Earth. A living model that updates in real time, letting us test the future without breaking the present. And the race to build it is already underway.

Melanie (Mel) Langlotz is the founder and CEO of Geo AR Games, a game design studio that utilises augmented reality for “creating digital experiences that positively impact the world, fostering education and empowerment with simulations and serious games.”