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
- A. Schwassmann
- Discovery site
- Bergedorf Obs.
- Discovery date
- 18 November 1922
- Pronunciation
- / ʃ w æ s ˈ m æ n i ə , ʃ v ɑː s -/
- Named after
- Friedrich Karl Arnold Schwassmann , (discoverer himself)
- Alternative designations
- A922 WD · 1922 MW, 1935 UE · 1935 UF
- Minor planet category
- main-belt · ( middle ) , background
- Observation arc
- 96.49 yr (35,244 d)
- Aphelion
- 3.3261 AU
- Perihelion
- 1.9915 AU
- Semi major axis
- 2.6588 AU
- Orbital period sidereal
- 4.34 yr (1,584 d)
- Mean anomaly
- 83.840 °
- Mean motion
- 0° 13 38.28 / day
- Inclination
- 14.700°
- Longitude of ascending node
- 243.40°
- Argument of perihelion
- 165.73°
- Mean diameter
- 12.20 ± 1.12 km 12.630 ± 0.124 km 12.86 ± 0.8 km
via Wikipedia infobox
Wikidata facts
- Diameter
- 12.63
- Orbital period
- 1586.027121299011
Show 14 more facts
- provisional designation
- A922 WD
- time of discovery or invention
- 1922-11-18
- orbital inclination
- 14.68937872885168
- argument of periapsis
- 165.6830529946464
- albedo
- 0.306
- rotation period
- 107.85
- absolute magnitude
- 11.82
- orbital eccentricity
- 0.2493360381068794
- semi-major axis of an orbit
- 2.661591832206262
- periapsis
- 1.997961069706322
- apoapsis
- 3.325222594706201
- longitude of ascending node
- 243.2974657769112
- mean anomaly
- 269.0997055776964
- time of periapsis
- 2461400.973145244
Sources (2)
via Wikidata · CC0
~4 min read
Article
989 Schwassmannia (prov. designation: A922 WD or 1922 MW) is a stony background asteroid and a slow rotator from the central regions of the asteroid belt, approximately 12.5 kilometers (7.8 miles) in diameter. It was discovered on 18 November 1922, by astronomer Friedrich Karl Arnold Schwassmann at the Bergedorf Observatory in Hamburg, Germany. The bright S/T-type asteroid has a long rotation period of 107.9 hours. It was named after the discoverer himself.
Orbit and classification