Space Science
A Beginner's Guide to Near-Earth Objects
Near-Earth objects are asteroids and comets whose orbits bring them close to Earth. Here is how to read them without panic.
What counts as a near-Earth object
A near-Earth object, often shortened to NEO, is an asteroid or comet with an orbit that approaches Earth's neighborhood. Most are small, distant, and safely monitored.
NASA's NeoWs service helps developers and researchers inspect close-approach windows, miss distance, velocity, size estimates, and hazard flags.
Close does not mean dangerous
Astronomical distance is enormous. A close approach can still be millions of kilometers away. That is why COSMOS AI displays miss distance and hazard status together instead of relying on dramatic language.
Potentially hazardous classification is a monitoring category. It does not mean an impact is expected.
How COSMOS uses NeoWs
The Daily Briefing and Earth Dashboard use NeoWs to summarize how many objects are visible in the current window and which listed object is closest.
When NASA data is unavailable, COSMOS should say so clearly rather than filling the gap with fake live values.