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
- L. Boyer
- Discovery site
- Algiers Obs.
- Discovery date
- 17 November 1936
- Named after
- Charles Tirel , (discoverer's friend)
- Alternative designations
- 1936 WA · 1930 UQ
- Minor planet category
- main-belt · ( outer ) , Tirela
- Observation arc
- 86.96 yr (31,762 days)
- Aphelion
- 3.8513 AU
- Perihelion
- 2.4001 AU
- Semi major axis
- 3.1257 AU
- Orbital period sidereal
- 5.53 yr (2,018 days)
- Mean anomaly
- 316.88 °
- Mean motion
- 0° 10 42.24 / day
- Inclination
- 15.631°
- Longitude of ascending node
- 210.10°
- Argument of perihelion
- 111.65°
- Mean diameter
- 14.67 ± 0.62 km 15.697 ± 0.285 km
- Synodic rotation period
- 13.356 h
via Wikipedia infobox
Wikidata facts
- Diameter
- 15.697
- Orbital period
- 2023.843248065236
- Image
- 001400-asteroid shape model (1400) Tirela.png
Show 14 more facts
- provisional designation
- 1936 WA
- time of discovery or invention
- 1936-11-17
- orbital inclination
- 15.58579295367428
- orbital eccentricity
- 0.2341044358200689
- periapsis
- 2.398217224288097
- apoapsis
- 3.864300373280038
- semi-major axis of an orbit
- 3.131258798784068
- mean anomaly
- 130.5307186668965
- longitude of ascending node
- 209.7687800072136
- argument of periapsis
- 112.9333242520596
- absolute magnitude
- 11.45
- albedo
- 0.216
- rotation period
- 15.45
- time of periapsis
- 2460266.6841287804
Sources (2)
via Wikidata · CC0
~3 min read
Article
1400 Tirela (provisional designation 1936 WA) is an asteroid and the parent body of the Tirela family, located in the outer regions of the asteroid belt. It was discovered on 17 November 1936, by French astronomer Louis Boyer at the Algiers Observatory in North Africa. The asteroid has a rotation period of 13.4 hours and measures approximately 16 kilometers (9.9 miles) in diameter. It was named after Charles Tirel, a friend of the discoverer.
Orbit and classification