File:147Protogeneia_(Lightcurve_Inversion).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
- Lipót Schulhof
- Discovery date
- 10 July 1875
- Pronunciation
- / ˌ p r ɒ t oʊ dʒ ɪ ˈ n iː ə /
- Named after
- Protogeneia
- Alternative designations
- A875 PA
- Minor planet category
- Main belt
- Observation arc
- 132.02 yr (48222 d)
- Aphelion
- 3.2230 AU (482.15 Gm )
- Perihelion
- 3.04727 AU (455.865 Gm)
- Semi major axis
- 3.13512 AU (469.007 Gm)
- Orbital period sidereal
- 5.55 yr (2027.6 d )
- Average orbital speed
- 16.82 km/s
- Mean anomaly
- 92.9051 °
- Mean motion
- 0° 10 39.184 / day
- Inclination
- 1.9309°
- Longitude of ascending node
- 248.357°
- Argument of perihelion
- 100.692°
- Earth moid
- 2.03996 AU (305.174 Gm)
via Wikipedia infobox
Wikidata facts
- Diameter
- 132.93
- Orbital period
- 2029.622722011352
- Image
- 147Protogeneia (Lightcurve Inversion).png
Show 15 more facts
- time of discovery or invention
- 1875-07-10
- orbital inclination
- 1.932861899645742
- albedo
- 0.0492
- Commons category
- 147 Protogeneia
- provisional designation
- A875 NA
- rotation period
- 7.8528
- absolute magnitude
- 8.73
- orbital eccentricity
- 0.02202213450664811
- semi-major axis of an orbit
- 3.137217239922908
- periapsis
- 3.068129019888751
- apoapsis
- 3.206305459957066
- longitude of ascending node
- 248.2035584041672
- argument of periapsis
- 103.5492515322589
- mean anomaly
- 333.1911330464513
- time of periapsis
- 2461151.644126445
Sources (2)
via Wikidata · CC0
~2 min read
Article
147 Protogenia is a main belt asteroid that was discovered by Hungarian astronomer Lipót Schulhof on July 10, 1875, from the Vienna Observatory; it was his only asteroid discovery. Its name is Greek for "first born" and was chosen by Karl L. Littrow in allusion to the fact that this was the first asteroid discovered by an astronomer who was already known for work in other fields of astronomy.
This object has a low orbital eccentricity and inclination. With an orbital period roughly double that of the planet Jupiter, it has been identified as a member of the Hecuba group of asteroids that share a 2:1 mean-motion orbital resonance with the giant planet. Based upon its spectrum, it has a Tholen classification as a C-type asteroid, which indicates that it has a dark surface and probably a primitive composition of carbonaceous material.