38 Leda

Also known as (38) Leda, Leda

main-belt asteroid

Picture of the Day · NASA

Pathfinder on Mars

2026-07-04

On July 4th, 1997, using its own array of fireworks, a parachute, and a cocoon of airbags, the Mars Pathfinder spacecraft bounced like a giant beach ball at least 15 times before it came to rest on the surface of Mars at 10:07 AM Pacific Daylight Time. After its then novel airbag-assisted landing sequence was completed, Pathfinder transmitted this color mosaic to mission operators on Earth. In the scene from another world, the Mars Sojourner robot rover is visible in the foreground, crouched on top of the unfolded Pathfinder. About the size of a large house cat, the six-wheeled, solar-powered Sojourner became the first successful Martian rover. Surrounding Pathfinder are deflated airbags and the rock-strewn terrain of the Ares Vallis floodplain. In the distance Martian hills appear against a dusty brownish sky. The Pathfinder lander was subsequently renamed the Carl Sagan Memorial Station.

via NASA APOD

Key facts

Discovered by: J. Chacornac
Discovery date: January 12, 1856
Designation: (38) Leda
Pronunciation: / ˈ l iː d ə /
Named after: Leda
Alternative names: A904 SF; 1949 QO 2
Minor planet category: Main belt
Adjectives: Ledean / l ɪ ˈ d iː ə n / (Latin Lēdæ-us )
Aphelion: 472.587 million km (3.159 AU)
Perihelion: 348.232 million km (2.328 AU)
Semi major axis: 410.409 million km (2.743 AU )
Orbital period sidereal: 1659.725 d (4.54 a )
Average orbital speed: 17.88 km/s
Mean anomaly: 107.567°
Inclination: 6.955°
Longitude of ascending node: 295.890°
Argument of perihelion: 168.804°
Dimensions: 92.255 ± 0.490 km

via Wikipedia infobox

Wikidata facts

Diameter: 92.255
Orbital period: 1658.962269266565
Image: 38Leda (Lightcurve Inversion).png

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provisional designation: A856 AA
time of discovery or invention: 1856-01-12
orbital inclination: 6.951653968605399
albedo: 0.055
Commons category: 38 Leda
rotation period: 12.838
absolute magnitude: 8.49
orbital eccentricity: 0.1509282371516316
semi-major axis of an orbit: 2.742576315840862
periapsis: 2.328644107237184
apoapsis: 3.15650852444454
longitude of ascending node: 295.4934542683404
argument of periapsis: 169.7834316347734
mean anomaly: 165.7611627025203
time of periapsis: 2460236.6346815745

Sources (2)

via Wikidata · CC0

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Article

38 Leda is a large, dark main-belt asteroid that was discovered by French astronomer J. Chacornac on January 12, 1856, and named after Leda, the mother of Helen of Troy in Greek mythology. In the Tholen classification system, it is categorized as a carbonaceous C-type asteroid, while the Bus asteroid taxonomy system lists it as a Cgh asteroid. The spectra of the asteroid displays evidence of aqueous alteration.

Leda has been studied by radar. During 2002, 38 Leda was observed by radar from the Arecibo Observatory. The return signal matched an effective diameter of 116 ± 13 km. This is consistent with some asteroid dimensions computed through other means. Based upon a light curve that was generated from photometric observations of this asteroid at Pulkovo Observatory, it has a rotation period of 12.834 ± 0.001 hours and varies in brightness by 0.15 ± 0.01 in magnitude.