211 Isolda

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

Johann Palisa

Discovery date

10 December 1879

Pronunciation

/ ɪ ˈ z oʊ l d ə /

Named after

Iseult

Alternative designations

A879 XA, 1912 AB, 1912 BA, 1950 FM

Minor planet category

Main belt

Adjectives

Isoldian / ɪ ˈ z oʊ l d i ə n /

Observation arc

136.19 yr (49742 d)

Aphelion

3.53270 AU (528.484 Gm )

Perihelion

2.5514 AU (381.68 Gm)

Semi major axis

3.04205 AU (455.084 Gm)

Orbital period sidereal

5.31 yr (1938.0 d )

Average orbital speed

17.08 km/s

Mean anomaly

260.142 °

Mean motion

0° 11 8.74 / day

Inclination

3.8856°

Longitude of ascending node

263.644°

Argument of perihelion

173.522°

via Wikipedia infobox

Wikidata facts

Diameter

141.125

Orbital period

1943.634558950218

via Wikidata · CC0