File:215_Oenone.png · Wikimedia Commons · See Wikimedia Commons
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
- Viktor Knorre
- Discovery date
- 7 April 1880
- Pronunciation
- / iː ˈ n oʊ n iː /
- Named after
- Oenōnē
- Alternative designations
- A880 GA
- Minor planet category
- Main belt
- Observation arc
- 110.31 yr (40,289 d)
- Aphelion
- 2.87 AU (428.78 Gm )
- Perihelion
- 2.67 AU (398.77 Gm)
- Semi major axis
- 2.77 AU (413.78 Gm)
- Orbital period sidereal
- 4.60 yr (1,680.2 d)
- Average orbital speed
- 17.91 km/s
- Mean anomaly
- 90.9597 °
- Mean motion
- 0° 12 51.343 / day
- Inclination
- 1.68583°
- Longitude of ascending node
- 25.0036°
- Argument of perihelion
- 315.903°
- Dimensions
- 46 ± 1 km , 48 ± 1 km
via Wikipedia infobox
Wikidata facts
- Diameter
- 35.21
- Orbital period
- 1681.937000195669
Show 15 more facts
- time of discovery or invention
- 1880-04-07
- orbital inclination
- 1.680497964505575
- provisional designation
- A880 GA
- albedo
- 0.243
- rotation period
- 27.937
- Commons category
- 215 Oenone
- absolute magnitude
- 9.59
- orbital eccentricity
- 0.03380951226391258
- semi-major axis of an orbit
- 2.767839259270062
- periapsis
- 2.674259963889232
- apoapsis
- 2.861418554650892
- longitude of ascending node
- 24.86542704390958
- argument of periapsis
- 320.0821088818636
- mean anomaly
- 95.04036285422679
- time of periapsis
- 2460556.4669366763
Sources (2)
via Wikidata · CC0
~1 min read
Article
215 Oenone is a typical main belt asteroid. It was discovered by the Russian astronomer Viktor Knorre on April 7, 1880, in Germany, and was the second of his four asteroid discoveries. The asteroid is named after Oenone, a nymph in Greek mythology.
This body is orbiting the Sun with a period of 4.60 years and a low ellipticity (ovalness) of 0.036. The orbital plane is inclined by 1.7° to the plane of the ecliptic. Light curve data gives a synodic rotation period of 27.93±0.01 h, during which it varies in brightness with an amplitude of 0.18±0.02 magnitudes. The cross-section diameter is 36 km. It is classified as an S-type asteroid in the Tholen taxonomy, suggesting a siliceous (stony) composition.