1543 Bourgeois

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

E. Delporte

Discovery site

Uccle Observatory

Discovery date

21 September 1941

Named after

Paul Bourgeois , (Belgian astronomer)

Alternative designations

1941 SJ · A911 MF

Minor planet category

main-belt · ( middle ) , background

Observation arc

75.81 yr (27,689 days)

Aphelion

3.4854 AU

Perihelion

1.7812 AU

Semi major axis

2.6333 AU

Orbital period sidereal

4.27 yr (1,561 days)

Mean anomaly

307.06 °

Mean motion

0° 13 50.52 / day

Inclination

11.021°

Longitude of ascending node

287.95°

Argument of perihelion

25.799°

Dimensions

11.985 ± 0.673 km , 16.73 km (calculated)

Synodic rotation period

2.48 ± 0.01 h

via Wikipedia infobox

Wikidata facts

Instance of

asteroid

Named after

Paul Bourgeois

Followed by

1544 Vinterhansenia

Follows

1542 Schalén

Parent body

Sun

Minor-planet group

asteroid belt

Diameter

11.985

Orbital period

1558.286694673321

via Wikidata · CC0