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
- J. Palisa
- Discovery site
- Vienna Obs.
- Discovery date
- 29 September 1911
- Alternative designations
- 1911 MS
- Observation arc
- 113.31 yr (41,388 d)
- Aphelion
- 3.6666 AU (548.52 Gm )
- Perihelion
- 2.4451 AU (365.78 Gm)
- Semi major axis
- 3.0559 AU (457.16 Gm)
- Orbital period sidereal
- 5.34 yr (1,951.2 d)
- Mean anomaly
- 5.10173 °
- Mean motion
- 0° 11 4.2 / day
- Inclination
- 6.9294°
- Longitude of ascending node
- 38.538°
- Argument of perihelion
- 174.377°
- Mean radius
- 36.47 ± 2.45 km
- Synodic rotation period
- 17.447 h (0.7270 d )
- Geometric albedo
- 0.0399 ± 0.006
via Wikipedia infobox
~1 min read
Encyclopedic overview
718 Erida is a minor planet orbiting the Sun. It was discovered at Vienna on September 29, 1911, by Austrian astronomer Johann Palisa, and was named for Erida Leuschner, daughter of astronomer Armin Otto Leuschner. It is orbiting at a distance of 3.06 AU with a period of 5.34 yr and an eccentricity of 0.20. The orbital plane of this asteroid is inclined by an angle of 6.9° to the plane of the ecliptic.
Photometric observations made during 2009 were used to produce a light curve for this asteroid that showed a rotation period of 17.447±0.002 h with a brightness variation of 0.37 in magnitude. It spans a girth of approximately 72 km.
Excerpted from Wikipedia’s “Q156718” article, available under the CC BY-SA 4.0 licence.