A recent scientific meeting revealed that there are roughly 25,000 known asteroids large enough to destroy cities, but only about 40% have been cataloged. This means that up to 60% of these objects remain undetected, making our planet vulnerable to a regional catastrophe with little time to respond.
NASA’s acting Planetary Defense Officer, Dr. Kelly Fast, detailed the scope of this blind spot, stating that many asteroids are dark or positioned in parts of the sky that telescopes struggle to monitor. This makes it challenging for scientists to detect and track these objects, which is crucial for developing a strategy to deflect one.
A single late discovery can force governments to confront a regional catastrophe with little time to respond. The lack of early sightings from different angles also makes orbit forecasts fuzzy, making it difficult for mission planners to act with confidence.
NASA plans to launch the Near-Earth Object Surveyor, an infrared space telescope built to find dark asteroids by their heat. This telescope will help boost warning time and narrow impact probabilities, guiding planning and decision-making.
However, finding and tracking every risky asteroid is slow work, and it competes with many other missions for money and attention. Without sustained investment in telescopes, data pipelines, and personnel, the world relies on luck rather than science to detect asteroids.
The launch of the Near-Earth Object Surveyor is planned no earlier than September 2027, and it’s essential to continue investing in asteroid detection and tracking to make our planet’s defenses practical.
Source: https://www.earth.com/news/nasa-warns-that-over-15000-city-killing-asteroids-orbit-earth-undetected