1091 Spiraea

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

K. Reinmuth

Discovery site

Heidelberg Obs.

Discovery date

26 February 1928

Pronunciation

/ s p aɪ ˈ r iː ə /

Named after

Spiraea , (genus of shrubs )

Alternative designations

1928 DT · 1934 CN 1 , 1938 UR · 1964 XH

Minor planet category

main-belt · ( outer ) , Cybele · background

Observation arc

89.27 yr (32,606 days)

Aphelion

3.6484 AU

Perihelion

3.2077 AU

Semi major axis

3.4281 AU

Orbital period sidereal

6.35 yr (2,318 days)

Mean anomaly

110.37 °

Mean motion

0° 9 19.08 / day

Inclination

1.1554°

Longitude of ascending node

80.790°

Argument of perihelion

12.062°

Dimensions

32.78 km (calculated) , 35.178 ± 0.108 km , 39.92 ± 17.85 km , 40.280 ± 0.455 km , 40.52 ± 0.91 km

via Wikipedia infobox

Wikidata facts

Diameter

35.178

Orbital period

2308.36963707537

via Wikidata · CC0