File:234_Barbara.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
- C. H. F. Peters
- Discovery date
- 12 August 1883
- Named after
- Saint Barbara ?
- Alternative designations
- A883 PA, 1942 RL 1 , 1953 RE,1975 XP
- Minor planet category
- Main belt
- Observation arc
- 131.26 yr (47944 d)
- Aphelion
- 2.97153 AU (444.535 Gm )
- Perihelion
- 1.79939 AU (269.185 Gm)
- Semi major axis
- 2.38546 AU (356.860 Gm)
- Orbital period sidereal
- 3.68 yr (1345.7 d )
- Average orbital speed
- 19.28 km/s
- Mean anomaly
- 16.9454 °
- Mean motion
- 0° 16 3.05 / day
- Inclination
- 15.3746°
- Longitude of ascending node
- 144.553°
- Argument of perihelion
- 192.344°
- Dimensions
- 43.75 ± 1.0 km , 45.62 ± 1.93 km
- Mass
- (0.44 ± 1.45) × 10 kg
via Wikipedia infobox
Wikidata facts
- Diameter
- 45.476
- Orbital period
- 1344.84043886537
- Image
- Asteroid Barbara (artist's impression) (eso0904a).jpg
Show 15 more facts
- provisional designation
- A883 PA
- time of discovery or invention
- 1883-08-12
- orbital inclination
- 15.38441896835477
- albedo
- 0.205
- Commons category
- 234 Barbara
- rotation period
- 26.4744
- absolute magnitude
- 9.12
- orbital eccentricity
- 0.2461141284446203
- semi-major axis of an orbit
- 2.384413407671648
- periapsis
- 1.797575579990873
- apoapsis
- 2.971251235352423
- longitude of ascending node
- 144.4341333200451
- argument of periapsis
- 192.311559060752
- mean anomaly
- 206.5565854331106
- time of periapsis
- 2461573.713636075
Sources (2)
via Wikidata · CC0
~2 min read
Article
234 Barbara is a main belt asteroid that was discovered by German-American astronomer Christian Heinrich Friedrich Peters on August 12, 1883, in Clinton, New York. The object is orbiting the Sun with a semimajor axis of 2.385 AU, a period of 3.68 years, and an eccentricity of 0.25. The orbital plane is inclined by 15.37° to the plane of the ecliptic. It is classified as a stony S-type asteroid based upon its spectrum. The mean diameter of this object is estimated as 45.6 km. It has a rotation rate of 26.5 hours, or a little over a day. It is possibly named for Saint Barbara, patron saint of mathematicians.
Observations of light curves and stellar occultations suggest the surface exhibits large concave areas. Polarimetric study of this asteroid reveals anomalous properties that suggests the regolith consists of a mixture of low and high albedo material. This may have been caused by fragmentation of an asteroid substrate with the spectral properties of CO3/CV3 carbonaceous chondrites. It is the prototype for a class of asteroids called "Barbarians" that display a strong infrared absorption band at 2μm, which is a characteristic of an FeO–enriched spinel mineral. Multiple other examples of this class have since been discovered.