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
- August Kopff
- Discovery site
- Heidelberg
- Discovery date
- 18 January 1909
- Alternative designations
- 1909 FR
- Observation arc
- 109.68 yr (40062 d)
- Aphelion
- 3.1092 AU (465.13 Gm )
- Perihelion
- 2.8043 AU (419.52 Gm)
- Semi major axis
- 2.9568 AU (442.33 Gm)
- Orbital period sidereal
- 5.08 yr (1857.1 d )
- Mean anomaly
- 349.034 °
- Mean motion
- 0° 11 37.86 / day
- Inclination
- 8.4812°
- Longitude of ascending node
- 272.799°
- Argument of perihelion
- 276.733°
- Mean radius
- 14.435 ± 0.85 km
- Synodic rotation period
- 16.608 h (0.6920 d )
- Geometric albedo
- 0.2794 ± 0.037
via Wikipedia infobox
Wikidata facts
- Diameter
- 32.403
- Orbital period
- 1859.381282888927
Show 14 more facts
- provisional designation
- A906 PA
- time of discovery or invention
- 1909-01-18
- orbital inclination
- 8.489141635025012
- albedo
- 0.313
- rotation period
- 16.608
- absolute magnitude
- 9.66
- orbital eccentricity
- 0.04673882640605032
- semi-major axis of an orbit
- 2.95923884155748
- periapsis
- 2.820927491047883
- apoapsis
- 3.097550192067076
- longitude of ascending node
- 272.6530952665855
- argument of periapsis
- 273.4481816713095
- mean anomaly
- 291.9755521357013
- time of periapsis
- 2461351.842736494
Sources (2)
via Wikidata · CC0
~1 min read
Article
677 Aaltje is a main-belt minor planet orbiting the Sun, discovered by August Kopff at Heidelberg on January 18, 1909. It was named after the Dutch singer Aaltje Noordewier-Reddingius.
This object has a geometric albedo of 0.2794. Photometric observations during 2008 showed a rotation period of 16.6076 ± 0.0006 hours and a brightness variation of 0.30 ± 0.02 in magnitude.