File:000118-asteroid_shape_model_(118)_Peitho.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
- Karl Theodor Robert Luther
- Discovery date
- 15 March 1872
- Pronunciation
- / ˈ p aɪ θ oʊ /
- Named after
- Πειθώ Peithō
- Alternative designations
- A872 EA
- Minor planet category
- Main belt
- Adjectives
- Peithoian / p aɪ ˈ θ oʊ . i ə n /
- Observation arc
- 144.05 yr (52615 d)
- Aphelion
- 2.8353 AU (424.15 Gm )
- Perihelion
- 2.03988 AU (305.162 Gm)
- Semi major axis
- 2.43757 AU (364.655 Gm)
- Orbital period sidereal
- 3.81 yr (1390.1 d )
- Average orbital speed
- 18.95 km/s
- Mean anomaly
- 51.1620 °
- Mean motion
- 0° 15 32.328 / day
- Inclination
- 7.7427°
- Longitude of ascending node
- 47.701°
- Argument of perihelion
- 33.403°
via Wikipedia infobox
~2 min read
Encyclopedic overview
118 Peitho is a main-belt asteroid. It is probably an S-type asteroid, suggesting a siliceous mineralogy. It was discovered by R. Luther on March 15, 1872, and named after one of the two Peithos in Greek mythology. There have been two observed Peithoan occultations of a dim star: one was in 2000 and the other in 2003.
This body is orbiting the Sun with a period of 3.81 years and an eccentricity (ovalness) of 0.16. The orbital plane is inclined by 7.7° to the plane of the ecliptic. The cross-section diameter is ~42 km. In 2009, Photometric observations of this asteroid were made at the Palmer Divide Observatory in Colorado Springs, Colorado. The resulting asymmetrical light curve shows a synodic rotation period of 7.823 ± 0.002 hours with a brightness variation of 0.15 ± 0.02 in magnitude. This was reasonably consistent with independent studies performed in 1980 (7.78 hours) and 2009 (7.8033 hours). The lightcurve inversion process has been used to construct a model of this object, suggesting a blocky shape with flattened poles.
Excerpted from Wikipedia’s “118 Peitho” article, available under the CC BY-SA 4.0 licence.