190 Ismene

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

C. H. F. Peters , 1878

Discovery date

22 September 1878

Pronunciation

/ ɪ s ˈ m iː n iː /

Named after

Ismene

Alternative designations

A878 SA; 1947 QJ;, 1951 DB

Minor planet category

Main belt ( Hilda )

Observation arc

121.44 yr (44357 d)

Aphelion

4.6480 AU (695.33 Gm )

Perihelion

3.3248 AU (497.38 Gm)

Semi major axis

3.9864 AU (596.36 Gm)

Orbital period sidereal

7.96 yr (2907.2 d )

Mean anomaly

134.92 °

Mean motion

0° 7 25.788 / day

Inclination

6.1772°

Longitude of ascending node

175.48°

Argument of perihelion

271.47°

Mean radius

79.5 km , 90 km

Synodic rotation period

6.52 h (0.272 d )

via Wikipedia infobox

Wikidata facts

Instance of

asteroid

Named after

Ismene

Followed by

191 Kolga

Follows

189 Phthia

Parent body

Sun

Diameter

159.0

Orbital period

2916.510274979688

via Wikidata · CC0