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
- P. Wild
- Discovery site
- Zimmerwald Obs.
- Discovery date
- 6 February 1973
- Named after
- Basel (Swiss city)
- Alternative designations
- 1973 CA · 1953 DA, 1953 EY · 1955 WD, 1955 XD
- Minor planet category
- main-belt · ( inner )
- Observation arc
- 63.33 yr (23,133 days)
- Aphelion
- 2.4734 AU
- Perihelion
- 1.9765 AU
- Semi major axis
- 2.2250 AU
- Orbital period sidereal
- 3.32 yr (1,212 days)
- Mean anomaly
- 191.60 °
- Mean motion
- 0° 17 49.2 / day
- Inclination
- 8.4634°
- Longitude of ascending node
- 321.72°
- Time of perihelion
- 14 November 2025
- Argument of perihelion
- 134.56°
- Dimensions
- 5.710 ± 0.088 km , 6.25 ± 1.51 km , 6.322 ± 0.051 km , 7.82 km (calculated)
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Basel
- Followed by
- Q147039
- Follows
- Q544183
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 5.71
- Orbital period
- 1212.866819608551
Show 17 more facts
- discoverer or inventor
- Paul Wild
- site of astronomical discovery
- Zimmerwald Observatory
- provisional designation
- 1973 CA
- time of discovery or invention
- 1973-02-06
- orbital eccentricity
- 0.1112498771855516
- absolute magnitude
- 13.14
- orbital inclination
- 8.46394417225531
- periapsis
- 1.978135935909792
- apoapsis
- 2.473364851838135
- semi-major axis of an orbit
- 2.225750393873963
- mean anomaly
- 1.811542131984656
- longitude of ascending node
- 321.6701076085877
- argument of periapsis
- 134.9743634330949
- albedo
- 0.419
- rotation period
- 6.5287
- time of periapsis
- 2460994.3967795996
- epoch
- November 21, 2025
Sources (2)
via Wikidata · CC0
~2 min read
Encyclopedic overview
2033 Basilea, provisional designation 1973 CA, is a stony asteroid from the inner regions of the asteroid belt, approximately 6 kilometers in diameter. It was discovered on 6 February 1973, by astronomer Paul Wild at the Zimmerwald Observatory near Bern, Switzerland. The asteroid was named for the Swiss city of Basel. It came to perihelion in November 2025 and opposition on 23 January 2026 at apparent magnitude 15 in the constellation of Cancer.
Classification and orbit
Excerpted from Wikipedia’s “Q147037” article, available under the CC BY-SA 4.0 licence.