Caption: Growth of known number of NEAs and NEA-KMs (i.e., large NEAs) 1980 Jan01--2021 Jul05.

For updates, click NASA/JPL Center for Near Earth Object Studies (CNEOS, 1990s--): Discovery Statistics. See cumulative discovery graph and table at the link. The graph can be expanded to full screen in the upper right corner.

Features:

1. NASA Statistics: As of 2023 Jul06, we find:
   1. 32400 NEOs: i.e., near-Earth asteroids and comets.

   2. 32279 NEAs: i.e., near-Earth asteroids.

   3. 10503 NEA-140m: i.e., near-Earth asteroids of order or greater than 140 meters in size scale.

   4. 853 NEA-KMs: i.e., near-Earth asteroids of order or greater than 1 kilometers (km) in size scale.

      Variations in the definition of NEA-KMs may cause different references to give different values.

   5. 2343 PHAs: i.e., potentially hazardous asteroids: i.e., those approaching Earth by ≤ 0.05 AU ≅ 19.5 mean lunar orbital radii (r_earth_moon = 384402 km = 60.2687 Earth equatorial radii = 2.56957*10**(-3) AU) ≅ 1170 Earth equatorial radii (R_eq_⊕ = 6378.1370 km).

   6. 151 PHA-KMs: i.e., potentially hazardous asteroids of order or greater than 1 kilometers (km) in size scale.

   7. 121 NECs: i.e., near-Earth comets. The NEC number doesn't grow very rapidly. There were 40 as of 2000 Jan01.

2. The NEA and NEA-140m curves are growing approximately linearly (see NASA NEO Program statistics: Totals).

   This means that there are still many NEAs and NEA-140m's to discover. We are NOT beginning to exhaust the statistical population of these astro-bodies.

   In fact, there is no end to the number of NEAs since one can keep looking for smaller and smaller ones. But those that are less than ∼ 1 m in size scale (which are are better called meteoroids) usually pose a relatively small threat. See Wikipedia: NEO: Impact rate and Wikipedia: Impact event: Air bursts.

3. The NEA-KM curve seems to be plateauing (see NASA NEO Program statistics: Totals).

   This means that we are nearly exhausting the NEA-KM statistical population.

   Probably finding the very last NEA-KMs will take a long time since it takes an exhaustive search to find the very last ones.

4. As of 2023 Jul06, NO certain or probable Earth impactor has been found. Likely in the decades to come, some will be found. But likely they will be small and NOT dangerous---but maybe we will be unlucky.