549 Jessonda

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

Max Wolf

Discovery site

Heidelberg

Discovery date

15 November 1904

Pronunciation

German: [ jɛsɔndaː ]

Alternative designations

1904 PK

Observation arc

111.42 yr (40695 d)

Aphelion

3.3765 AU (505.12 Gm )

Perihelion

1.9899 AU (297.68 Gm)

Semi major axis

2.6832 AU (401.40 Gm)

Orbital period sidereal

4.40 yr (1605.3 d )

Mean anomaly

129.346 °

Mean motion

0° 13 27.3 / day

Inclination

3.9605°

Longitude of ascending node

291.421°

Argument of perihelion

158.166°

Mean radius

9.405 ± 0.35 km

Synodic rotation period

2.962 h (0.1234 d )

Geometric albedo

0.1971 ± 0.015

via Wikipedia infobox

Wikidata facts

Instance of

asteroid

Followed by

550 Senta

Follows

548 Kressida

Parent body

Sun

Minor-planet group

asteroid belt

Diameter

15.53

Orbital period

1608.560488365425

via Wikidata · CC0