Key facts
- Category
- Moons
- Object class
- Asteroid moon
- Scale fact
- 1.6 kmmaximum extent
- Host
- 243 Ida
Dactyl
1.6 kmmaximum extent
Explore Dactyl to scaleDetails
Dactyl is the tiny moon of the main-belt asteroid 243 Ida and the first asteroid moon ever discovered. Galileo photographed it during the 1993 Ida flyby, settling a long-running question about whether asteroids could keep natural satellites.
Galileo photographed Dactyl during its 28 August 1993 flyby of Ida, but the tiny companion was noticed only five months later as researchers examined the returned images. The discovery turned asteroid satellites from a theoretical possibility into an observed class of object; the images resolve Dactyl only as an irregular body about 1.6 kilometers across.
Links
- Wikipedia
- Dactyl on Wikipedia
Size neighbors
Objects near Dactyl on the scale
On the logarithmic size axis, Dactyl falls between 162173 Ryugu and 9969 Braille. The band uses nearby Moons records.
Sources
References for Dactyl
Measurements and descriptive context are compiled by the Scale of Space team from the references below. If you find an error, please let us know.
- Dactyl — Wikipedia
- Visual reference: Wikimedia Commons (Galileo 1993 / NASA / JPL, Public domain)
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About
Scale of Space is a scroll-based journey through the universe, placing objects on a single logarithmic scale so you can compare size across an unbroken range.
Guides explain selected parts of that range, while focused views filter the objects by subject.