--- title: "How many asteroids are there? about 1.4 million catalogued" description: "about 1.4 million catalogued How the figure is estimated, how confident it is, and what makes the scale graspable." url: https://atoneplace.net/how-many/known-asteroids/ site: "At One Place" --- # How many asteroids are there? **How many asteroids are there?: about 1.4 million catalogued** The entire main asteroid belt has about 3% of the Moon's mass, and Ceres alone accounts for a quarter of it. The popular image of a densely packed field is wrong by a factor of millions. The Minor Planet Center catalogue holds roughly 1.4 million asteroids with orbits good enough to be numbered or designated, of which about 38,000 are near-Earth asteroids. That is the count of known objects, not existing ones: the main belt is thought to contain perhaps 1 to 2 million asteroids larger than 1 km and many millions more below that. Surveys have found an estimated 95% of near-Earth asteroids larger than 1 km — the ones that would be globally catastrophic — but well under half of those in the 140 m range that could destroy a city. ## How the figure is arrived at Automated sky surveys photograph the same field repeatedly; software finds points of light that move against the fixed stars. Three or more nights of observations fix an orbit well enough for a provisional designation, and observations at a later opposition confirm it well enough for a permanent number. ## How confident it is - **Low estimate:** 1,300,000 - **High estimate:** 1,500,000 - **Spread:** 1.2× between the bounds > The catalogue grows by tens of thousands a year as surveys such as Pan-STARRS and the Vera Rubin Observatory come up to speed. Figure as of 2025. ## Other space and the universe counts - [How many stars are there in the universe?](https://atoneplace.net/how-many/stars-in-the-universe/) — about 200 billion trillion - [How many stars are there in the Milky Way?](https://atoneplace.net/how-many/stars-in-the-milky-way/) — between 100 billion and 400 billion - [How many atoms are there in the universe?](https://atoneplace.net/how-many/atoms-in-the-universe/) — about 10^80 - [How many galaxies are there?](https://atoneplace.net/how-many/galaxies-in-the-universe/) — hundreds of billions — possibly 2 trillion - [How many satellites are in orbit?](https://atoneplace.net/how-many/satellites-in-orbit/) — about 12,000 active satellites - [How many moons are there in the solar system?](https://atoneplace.net/how-many/moons-in-the-solar-system/) — about 900 confirmed, and the number keeps moving - [How many planets are there in the galaxy?](https://atoneplace.net/how-many/planets-in-the-milky-way/) — at least 100 billion — probably more planets than stars - [How many stars can you see with the naked eye?](https://atoneplace.net/how-many/stars-visible-to-the-naked-eye/) — about 9,000 over the whole sky; roughly 2,500 at once - [How many constellations are there?](https://atoneplace.net/how-many/constellations/) — exactly 88 - [How much space junk is there?](https://atoneplace.net/how-many/space-debris/) — about 40,000 tracked objects, and over 130 million fragments too small to track ## Common questions ### How many asteroids are there? about 1.4 million catalogued ### How is that estimated? Automated sky surveys photograph the same field repeatedly; software finds points of light that move against the fixed stars. Three or more nights of observations fix an orbit well enough for a provisional designation, and observations at a later opposition confirm it well enough for a permanent number. ## Related pages - [How many stars are there in the universe?](https://atoneplace.net/how-many/stars-in-the-universe/) - [How many stars are there in the Milky Way?](https://atoneplace.net/how-many/stars-in-the-milky-way/) - [How many atoms are there in the universe?](https://atoneplace.net/how-many/atoms-in-the-universe/) - [How many galaxies are there?](https://atoneplace.net/how-many/galaxies-in-the-universe/) - [How many satellites are in orbit?](https://atoneplace.net/how-many/satellites-in-orbit/) - [How many moons are there in the solar system?](https://atoneplace.net/how-many/moons-in-the-solar-system/) - [How many planets are there in the galaxy?](https://atoneplace.net/how-many/planets-in-the-milky-way/) - [How many stars can you see with the naked eye?](https://atoneplace.net/how-many/stars-visible-to-the-naked-eye/) - [How many people are there in the world?](https://atoneplace.net/how-many/people-alive-right-now/) - [How many countries are there in the world?](https://atoneplace.net/how-many/countries/) - [How many bones are in the human body?](https://atoneplace.net/how-many/bones-in-the-human-body/) - [How many grains of sand are there on Earth?](https://atoneplace.net/how-many/grains-of-sand-on-earth/) - [How many ants are there in the world?](https://atoneplace.net/how-many/ants-on-earth/) - [How many trees are there in the world?](https://atoneplace.net/how-many/trees-on-earth/) ## Sources - NASA — National Aeronautics and Space Administration (https://www.nasa.gov/) [Public domain (US Government)]