A full disc view of Bennu, whoing its surface littered with giant boulders.

Asteroids, Comets & Meteors

Our solar system's small bodies pack big surprises.

Exploring asteroids

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Active Missions

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Mission On Deck

Asteroids

Rocky leftovers from planet formation.

Comets

Cosmic snowballs of gas and dust.

Meteors

Bits of debris that fall through the atmosphere.

Seal shows a guard in a castle turret using a telescope to watch out for asteroids and comets in the sky.

Planetary Defense

Protect Earth from impacts.

Overview

Asteroids, comets, and meteors are chunks of rock, ice, and metal left over from the formation of our solar system 4.6 billion years ago. They are a lot like a fossil record of our early solar system. There are currently about 1.4 million known asteroids, and more than 3,900 known comets (including comet fragments).

Explore the 3D world of asteroids, comets, and NEOs. Learn about past and future missions, tracking and predicting orbits, and close approaches to Earth.

NASA/JPL-Caltech

Asteroids, Comets and Meteors Stories

NASA Lucy Images Reveal Asteroid Dinkinesh to be Surprisingly Complex

NASA’s OSIRIS-APEX Unscathed After Searing Pass of Sun

Two identical scenes are seen in a pair of side-by-side images. Against the pitch-black background of space, a boxy metallic satellite dominates the foreground. Glints of light are bouncing off the shiniest parts of the structure.

NASA’s Psyche Fires Up Its Sci-Fi-Worthy Thrusters

Hubble Goes Hunting for Small Main Belt Asteroids

This is a Hubble Space Telescope image of the barred spiral galaxy UGC 12158. The majestic galaxy has a pinwheel shape made up of bright blue stars wound around a yellow-white hub of central stars. The hub has a slash of stars across it, called a bar. The galaxy is tilted face-on to our view from Earth. A slightly s-shaped white line across the top is a Hubble image is of an asteroid streaking across Hubble's view. It looks dashed because the image is a combination of several exposures of the asteroid flying by like a race car.

Asteroid, Comets and Meteors

14 Images

These three radar images of near-Earth asteroid 2003 SD220 were obtained on Dec. 15-17. This will be the asteroid's closest approach in more than 400 years and the closest until 2070.

This frame from a movie of asteroid 2014 JO25 was generated using radar data collected by NASA 230-foot-wide 70-meter Deep Space Network antenna at Goldstone, California on April 19, 2017.

This radar image of asteroid 2005 YU55 was obtained NASA Deep Space Network antenna in Goldstone, Calif. on Nov. 7, 2011, when the space rock was at 3.6 lunar distances, which is about 860,000 miles, or 1.38 million kilometers, from Earth.

This image of asteroid 2011 MD was taken by NASA Spitzer Space Telescope in Feb. 2014, over a period of 20 hours.

Two large and one smaller bright, blue-white dots surrounded with a blue cloud.

Two Very Different Asteroids

Radar Model of Asteroid 216 Kleopatra

Comet 2i/borisov as seen by hubble

This collage of radar images of near-Earth asteroid 1999 JD6 was collected by NASA scientists on July 25, 2015. The asteroid is between 660-980 feet 200-300 meters in diameter.

An illustration of asteroid Psyche in space. Large craters can be seen on the gray-colored, potato-shaped asteroid.

To date, NASA-sponsored surveys have provided over 95% of all Near-Earth Object discoveries.

NASA

Planetary Defense Coordination Office (PDCO)

Resources

Lucy Mission Resource Package
Activities that can be done at home as well as videos, animations, stories, and articles.
For Kids: Asteroids, Comets & Meteors
Facts and activities for K-4 explorers.
NASA Photojournal: Small Bodies
Shooting stars are actually bits of debris that fall through our atmosphere.

Keep Exploring

Discover More Topics From NASA

Pluto

This full disc view of Pluto features bright region that looks like a heart on the side of the dwarf planet.

Kuiper Belt

Illustration of spacecraft near a giant space rock far from the Sun.

Oort Cloud

This image shows comet C/2018 Y1 Iwamoto as imaged in multiple exposures of infrared light by NASA's Near-Earth Object Wide-field Survey Explorer (NEOWISE) space telescope.

Skywatching

A man looks through a telescope at twilight.