Q144755

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

Indiana University , ( Indiana Asteroid Program )

Discovery site

Goethe Link Obs.

Discovery date

15 December 1957

Named after

William D. McElroy , (American biochemist)

Alternative designations

1957 XE · 1930 YP, 1950 NX · 1950 OM

Minor planet category

main-belt · ( outer )

Observation arc

66.70 yr (24,364 days)

Aphelion

3.2153 AU

Perihelion

2.9115 AU

Semi major axis

3.0634 AU

Orbital period sidereal

5.36 yr (1,958 days)

Mean anomaly

106.92 °

Mean motion

0° 11 1.68 / day

Inclination

15.759°

Longitude of ascending node

298.77°

Argument of perihelion

89.936°

Dimensions

17.47 ± 0.64 km , 20.89 km (derived) , 21.09 ± 0.67 km , 21.14 ± 1.0 km , 23.807 ± 0.154 , 24.065 ± 0.282 km

Synodic rotation period

8.016 ± 0.005 h , 8.0229 ± 0.0041 h (R) , 8.0262 ± 0.0020 h (R)

via Wikipedia infobox

Wikidata facts

Diameter

23.807

Orbital period

1959.948770510204

via Wikidata · CC0