Q158330

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

J. Palisa

Discovery site

Vienna Obs.

Discovery date

27 October 1921

Pronunciation

/ s ʌ b ə ˈ m ɛər ə /

Named after

Latin for "very bitter" , (due to light pollution )

Alternative designations

A921 UL · A905 UL, 1921 KS · 1905 UL, 1923 NP

Minor planet category

main-belt · ( outer ) , background

Observation arc

114.20 yr (41,711 d)

Aphelion

3.4143 AU

Perihelion

2.6816 AU

Semi major axis

3.0479 AU

Orbital period sidereal

5.32 yr (1,944 d)

Mean anomaly

169.17 °

Mean motion

0° 11 6.72 / day

Inclination

9.0506°

Longitude of ascending node

30.681°

Argument of perihelion

9.6350°

Mean diameter

19.835 ± 0.536 km 21.23 ± 1.17 km

via Wikipedia infobox

Wikidata facts

Diameter

19.835

Orbital period

1946.008425002909

via Wikidata · CC0