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
- 22 January 1917
- Pronunciation
- / ɜːr ˈ s aɪ n ə /
- Alternative designations
- 1917 BD
- Observation arc
- 113.24 yr (41362 days)
- Aphelion
- 3.0938 AU (462.83 Gm )
- Perihelion
- 2.5013 AU (374.19 Gm)
- Semi major axis
- 2.7975 AU (418.50 Gm)
- Orbital period sidereal
- 4.68 yr (1709.1 d )
- Mean anomaly
- 247.967 °
- Mean motion
- 0° 12 38.304 / day
- Inclination
- 13.297°
- Longitude of ascending node
- 309.388°
- Argument of perihelion
- 21.338°
- Earth moid
- 1.49307 AU (223.360 Gm)
- Jupiter moid
- 2.21886 AU (331.937 Gm)
- Mean radius
- 14.66 ± 0.8 km
via Wikipedia infobox
Wikidata facts
- Diameter
- 34.561
- Orbital period
- 1706.842817092631
Show 16 more facts
- provisional designation
- A917 BE
- time of discovery or invention
- 1917-01-22
- orbital inclination
- 13.29572668995501
- catalog code
- A903 BB
- rotation period
- 9.386
- apparent magnitude
- 16
- albedo
- 0.116
- absolute magnitude
- 10.04
- orbital eccentricity
- 0.108657588074656
- semi-major axis of an orbit
- 2.795096038270751
- periapsis
- 2.491387644315225
- apoapsis
- 3.098804432226277
- longitude of ascending node
- 309.2075450836342
- argument of periapsis
- 21.0197778778248
- mean anomaly
- 245.0278753607308
- time of periapsis
- 2461545.6092919623
Sources (3)
via Wikidata · CC0
~1 min read
Article
860 Ursina is a minor planet orbiting the Sun that was discovered in 1917 by German astronomer Max Wolf. The origin of the name is unknown.
Photometric observations of this asteroid collected during 1999 show a rotation period of 9.386 ± 0.002 hours with a brightness variation of 0.22 magnitude.