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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

Y. Väisälä

Discovery site

Turku Obs.

Discovery date

15 October 1938

Named after

Rovaniemi (Finnish city)

Alternative designations

1938 UA · 1928 TL, 1951 SH

Minor planet category

main-belt · ( inner ) , Flora

Observation arc

88.74 yr (32,412 days)

Aphelion

2.5449 AU

Perihelion

1.9053 AU

Semi major axis

2.2251 AU

Orbital period sidereal

3.32 yr (1,212 days)

Mean anomaly

246.56 °

Mean motion

0° 17 49.2 / day

Inclination

6.7137°

Longitude of ascending node

27.804°

Argument of perihelion

37.101°

Dimensions

7.46 ± 1.30 km , 7.76 ± 0.71 km , 8.480 ± 0.167 km , 8.98 km (calculated) , 9.019 ± 0.070 km

Synodic rotation period

5.247 ± 0.001 h , 5.249 ± 0.002 h

via Wikipedia infobox

Wikidata facts

Instance of

asteroid

Named after

Rovaniemi

Followed by

1519 Kajaani

Follows

1517 Beograd

Parent body

Sun

Minor-planet group

asteroid belt

Diameter

8.48

Orbital period

1212.768535124377

Image

1518Rovaniemi (Lightcurve Inversion).png

via Wikidata · CC0