82 Alkmene

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

Karl Theodor Robert Luther

Discovery date

27 November 1864

Pronunciation

/ æ l k ˈ m iː n iː /

Named after

Alcmene

Minor planet category

Main belt

Adjectives

Alkmenean / æ l k ˈ m iː n i ə n /

Aphelion

3.3701 AU

Perihelion

2.1609 AU

Semi major axis

2.7655 AU

Orbital period sidereal

4.60 yr

Average orbital speed

17.70 km/s

Mean anomaly

192.56°

Inclination

2.8286°

Longitude of ascending node

25.507°

Argument of perihelion

111.27°

Dimensions

61 ± 1.5 km ( IRAS )

Mass

2.4 × 10 kg (assumed)

Synodic rotation period

12.999 h

via Wikipedia infobox

Wikidata facts

Diameter

57.621

Mass

240

Orbital period

1678.412735353029

Image

82Alkmene (Lightcurve Inversion).png

via Wikidata · CC0