Q157693

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

11 July 1918

Pronunciation

/ ˈ h iː l i oʊ /

Alternative designations

1918 DU

Adjectives

Helian / ˈ h iː l i ə n /

Observation arc

109.79 yr (40100 days)

Aphelion

3.6686 AU (548.81 Gm )

Perihelion

2.7362 AU (409.33 Gm)

Semi major axis

3.2024 AU (479.07 Gm)

Orbital period sidereal

5.73 yr (2093.2 d )

Mean anomaly

241.229 °

Mean motion

0° 10 19.164 / day

Inclination

26.077°

Longitude of ascending node

264.704°

Argument of perihelion

178.108°

Earth moid

1.75069 AU (261.899 Gm)

Jupiter moid

1.60187 AU (239.636 Gm)

via Wikipedia infobox

Wikidata facts

Diameter

109.568

Orbital period

2094.254367396165

via Wikidata · CC0