404 Arsinoë

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

Auguste Charlois

Discovery date

20 June 1895

Pronunciation

/ ɑːr ˈ s ɪ n oʊ . iː /

Named after

Arsinoe

Alternative designations

1895 BY

Minor planet category

Main belt

Adjectives

Arsinoean / ˌ ɑːr s ɪ n oʊ ˈ iː ə n /

Observation arc

116.88 yr (42691 d)

Aphelion

3.10936 AU (465.154 Gm )

Perihelion

2.07791 AU (310.851 Gm)

Semi major axis

2.59364 AU (388.003 Gm)

Orbital period sidereal

4.18 yr (1525.7 d )

Mean anomaly

41.5847 °

Mean motion

0° 14 9.46 / day

Inclination

14.1044°

Longitude of ascending node

92.6126°

Argument of perihelion

120.382°

Dimensions

97.71 ± 1.5 km , 96.97 ± 3.01 km

via Wikipedia infobox