249 Ilse

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

Discovery date

16 August 1885

Pronunciation

German: [ ˈɪlzə ]

Named after

Ilse

Alternative designations

A885 QA, 1973 PB

Minor planet category

Main belt

Observation arc

130.59 yr (47699 d)

Aphelion

2.89450 AU (433.011 Gm )

Perihelion

1.85992 AU (278.240 Gm)

Semi major axis

2.37721 AU (355.626 Gm)

Orbital period sidereal

3.67 yr (1338.8 d )

Average orbital speed

19.31 km/s

Mean anomaly

223.964 °

Mean motion

0° 16 8.065 / day

Inclination

9.61979°

Longitude of ascending node

334.727°

Argument of perihelion

42.3241°

Dimensions

34.83 ± 1.1 km

via Wikipedia infobox

Wikidata facts

Diameter

34.83

Orbital period

1339.688912942064

Image

000249-asteroid shape model (249) Ilse.png

via Wikidata · CC0