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
- Diameter
- 15.53
- Orbital period
- 1608.560488365425
Show 14 more facts
- provisional designation
- A904 WA
- time of discovery or invention
- 1904-11-15
- orbital inclination
- 3.954502785758186
- albedo
- 0.289
- rotation period
- 2.9713
- absolute magnitude
- 10.87
- orbital eccentricity
- 0.2561916273213069
- semi-major axis of an orbit
- 2.686742096076119
- periapsis
- 1.998421266289719
- apoapsis
- 3.375062925862519
- longitude of ascending node
- 291.26228411
- argument of periapsis
- 157.8929424021577
- mean anomaly
- 171.6913655581026
- time of periapsis
- 2460233.344592138
Sources (2)
via Wikidata · CC0
~1 min read
Article
549 Jessonda is a minor planet orbiting the Sun. According to the Catalogue of Minor Planet Names and Discovery Circumstances, it is "named presumably after the character in the opera of the same name by the German composer, conductor and violinist Ludwig Spohr (1784–1859), one of the leading composers in the early romantic period.' (Around 1904 Max Wolf named numerous asteroids he had discovered after female characters in opera.)
References