Dimorphos

Also known as (65803) Didymos I, (65803) I, S/2003 (65803) 1, Didymoon, Didymos I, Didymos B, Dimorphous

Dimorphos (formal designation (65803) Didymos I; provisional designation S/2003 (65803) 1) is a natural satellite or moon of the near-Earth asteroid 65803 Didymos, with which it forms a binary system. The moon was discovered on 20 November 2003 by Petr Pravec in collaboration with other astronomers worldwide. Dimorphos has a diameter of across its longest extent.

Key facts

Planet.inclination: with respect to ecliptic
Planet.name: Dimorphos
Planet.image: Dimorphos North-Up Image Composition (final 10 full-frame images).png
Planet.caption: High-resolution view of Dimorphos, created by combining the final 10 full-frame images obtained by DART's Didymos Reconnaissance and Asteroid Camera for Optical navigation (DRACO). Dimorphos is oriented so that its north pole is toward the top of the image. Taken seconds before impact on September 26, 2022.
Planet.discoverer: Petr Pravec et al.
Planet.discovery_site: Ondřejov Observatory
Planet.discovered: 20 November 2003
Planet.mpc_name: Didymos I
Planet.alt_names: S/2003 (65803) 1Didymos B"Didymoon"
Planet.named_after: Greek word for "having two forms"
Planet.satellite_of: 65803 Didymos
Planet.epoch: 26 September 2022 23:14:24.183 UTC(JD ; impact time)
Planet.semimajor: (pre-impact) (post-impact)
Planet.eccentricity: (pre-impact) or (post-impact)
Planet.avg_speed: (pre-impact)
Planet.dimensions:  m (±  m)
Planet.mean_diameter: (volume equivalent)
Planet.mass: (if density is )≈ (if same density as Didymos)

via Wikipedia infobox

~11 min read

Encyclopedic overview

10 sections

Contents

Discovery
Naming
Exploration
Size and shape
Surface
Orbit and rotation
See also
Footnotes
References
External links

Dimorphos is the smallest asteroid to be photographed and visited by a spacecraft. It was the target of the Double Asteroid Redirection Test (DART), a NASA space mission that deliberately collided a spacecraft with the moon on 26 September 2022 to alter its orbit around Didymos. Before the impact by DART, Dimorphos had a shape of an oblate spheroid with a surface covered in boulders but virtually no craters. The moon is thought to have formed when Didymos shed its mass due to its rapid rotation, which formed an orbiting ring of debris that conglomerated into a low-density rubble pile that became Dimorphos today.

Excerpted from Wikipedia’s “Dimorphos” article, available under the CC BY-SA 4.0 licence.