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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

K. Reinmuth

Discovery site

Heidelberg Obs.

Discovery date

14 September 1931

Pronunciation

/ ɪ m p ə ˈ r eɪ t r ɪ k s /

Named after

empress (in Latin)

Alternative designations

1931 RH · 1929 CX, 1950 DC 1 · 1957 OY, A913 EC · A915 TL, A924 GC

Minor planet category

main-belt · ( outer ) , Hygiea

Observation arc

101.75 yr (37,165 days)

Aphelion

3.3873 AU

Perihelion

2.7436 AU

Semi major axis

3.0654 AU

Orbital period sidereal

5.37 yr (1,960 days)

Mean anomaly

114.85 °

Mean motion

0° 11 0.96 / day

Inclination

4.5935°

Longitude of ascending node

204.77°

Argument of perihelion

51.583°

Dimensions

36.00 ± 0.42 km , 37.36 ± 9.71 km , 39.39 km (derived) , 39.52 ± 3.9 km , 42.006 ± 0.390 km , 42.777 ± 0.309 km , 43.64 ± 0.61 km

via Wikipedia infobox

Wikidata facts

Instance of

asteroid

Named after

emperor

Followed by

Q136955

Follows

1199 Geldonia

Parent body

Sun

Minor-planet group

asteroid belt

Diameter

42.006

Orbital period

1953.177458616772

via Wikidata · CC0