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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

Johann Palisa

Discovery date

25 April 1890

Alternative designations

A890 HA, 1954 UJ 3

Minor planet category

main-belt

Observation arc

124.62 yr (45516 d)

Aphelion

2.4273 AU (363.12 Gm )

Perihelion

2.01631 AU (301.636 Gm)

Semi major axis

2.22182 AU (332.380 Gm)

Orbital period sidereal

3.31 yr (1209.7 d )

Mean anomaly

115.293 °

Mean motion

0° 17 51.382 / day

Inclination

1.8555°

Longitude of ascending node

161.655°

Argument of perihelion

331.580°

Dimensions

14.97 ± 1.1 km , 19×12×11 km

Mass

~

Mean density

~2.7 g/cm

Synodic rotation period

4.313 h (0.1797 d ) , 0.180 d (4.32 h)

via Wikipedia infobox