141 Lumen

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

P. P. Henry

Discovery date

13 January 1875

Pronunciation

/ ˈ l uː m ə n / , / ˈ l uː m ɛ n /

Named after

Lumen: Récits de l'infini

Minor planet category

main-belt · ( middle ) , Eunomian interloper

Observation arc

138.63 yr (50635 d)

Aphelion

3.23723 AU (484.283 Gm )

Perihelion

2.09253 AU (313.038 Gm)

Semi major axis

2.66488 AU (398.660 Gm)

Orbital period sidereal

4.35 yr (1589.0 d )

Mean anomaly

292.477 °

Mean motion

0° 13 35.623 / day

Inclination

11.8967°

Longitude of ascending node

318.504°

Argument of perihelion

58.1076°

Dimensions

131.03 ± 2.9 km , 130 km , 131.35 ± 5.21 km

Mass

(8.25 ± 5.77) × 10 kg

Mean density

1.4 g/cm (estimate) , 6.95 ± 4.93 g/cm

via Wikipedia infobox