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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

Max Wolf

Discovery site

Heidelberg

Discovery date

16 November 1904

Pronunciation

German: [ ˈzɛntaː ]

Alternative designations

1904 PL

Observation arc

115.33 yr (42124 d)

Aphelion

3.1653 AU (473.52 Gm )

Perihelion

2.0115 AU (300.92 Gm)

Semi major axis

2.5884 AU (387.22 Gm)

Orbital period sidereal

4.16 yr (1521.1 d )

Mean anomaly

17.4133 °

Mean motion

0° 14 12.012 / day

Inclination

10.108°

Longitude of ascending node

270.702°

Argument of perihelion

45.342°

Mean radius

18.875 ± 1.9 km

Synodic rotation period

20.555 h (0.8565 d )

Geometric albedo

0.2215 ± 0.052

via Wikipedia infobox