Jupiter’s most defining attribute is undoubtedly its size. At roughly one-tenth the diameter of our Sun, Jupiter may have once had a chance at actually becoming a star itself. Still, size aside, every planet has one recognizable attribute that sets it apart — Saturn has its rings, Venus has its atmosphere, and Jupiter has its spot. The Great Red Spot has captivated astronomers for hundreds of years — this enormous storm of blood red clouds is wider than the entire planet Earth. Yet now, new images from NASA confirm that the observed trend in its size will continue: the Great Red Spot is now smaller than we’ve ever seen it before.

It’s thought that the spot was once as much as 24,855 miles (or 40,000 kilometers) across, but today it’s just 10,253 miles across (16,500 kilometers). In 2012, scientists noticed a sharp increase in the rate at which the storm was collapsing. In just the past year, it has shrunk by 559 miles (900 kilometers) — that’s more than the width of Texas. If the trend continues, the spot could reach a circular shape by the end 2040. That’s technically not very likely, since such a huge deformation would cause a lot of disruption to the surrounding jet-streams. It’s possible that the small eddies found along the exterior of the storm could be somehow siphoning off its kinetic energy, tiring it out and causing it to dissipate.

There’s speculation about whether the spot itself might be transient and destined to dissipate; given our myopic human-scale view of the universe, it’s possible that the Great Red Spot is really just a passing fad in Jovian weather patterns. It might only seem like a defining part of Jupiter’s identity thanks to that bias in our thinking.

The Great Red Spot actually sits atop much of the rest of the atmosphere, or at the very least reaches higher, a swirling vortex of gasses that have yet to be fully identified. The reddish color likely comes from red phosphorous or perhaps complex organic compounds that are still unknown.

Jupiter actually sports a number of “Little Red Spots” that occur in the northern hemisphere and are always short-lived. They usually come and go in less than a year, and their action may help scientists predict the future of Jupiter’s most important storm. If the trend in size continues, the face of Jupiter could change dramatically within our lifetime.