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
- R. M. West
- Discovery site
- La Silla Obs.
- Discovery date
- 24 October 1976
- Pronunciation
- / ˈ s t ɛ n t ər / ·
- Named after
- Stentor , (Greek mythology)
- Alternative designations
- 1976 UQ
- Minor planet category
- Jupiter trojan , Greek · background
- Adjectives
- Stentorian
- Observation arc
- 40.93 yr (14,949 d)
- Aphelion
- 5.7217 AU
- Perihelion
- 4.6714 AU
- Semi major axis
- 5.1965 AU
- Orbital period sidereal
- 11.85 yr (4,327 d)
- Mean anomaly
- 238.48 °
- Mean motion
- 0° 4 59.52 / day
- Inclination
- 39.261°
- Longitude of ascending node
- 131.32°
- Argument of perihelion
- 273.11°
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Stentor
- Followed by
- Q845602
- Follows
- Q851690
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 50.755
- Orbital period
- 4321.361990965557
Show 18 more facts
- discoverer or inventor
- Richard Martin West
- site of astronomical discovery
- La Silla Observatory
- provisional designation
- 1976 UQ
- time of discovery or invention
- 1976-10-24
- orbital eccentricity
- 0.1014016847443664
- orbital inclination
- 39.27499274343906
- periapsis
- 4.665667089635152
- apoapsis
- 5.718654826899625
- semi-major axis of an orbit
- 5.192160958267388
- mean anomaly
- 110.4222647958557
- longitude of ascending node
- 131.33022975
- argument of periapsis
- 274.8427374893705
- absolute magnitude
- 10.03
- Commons category
- 2146 Stentor
- albedo
- 0.082
- rotation period
- 16.4
- time of periapsis
- 2459675.015060986
- epoch
- November 21, 2025
via Wikidata · CC0
~3 min read
Encyclopedic overview
2146 Stentor /ˈstɛntər/ is a Jupiter trojan from the Greek camp, approximately 51 kilometers (32 miles) in diameter. It was discovered on 24 October 1976, by Danish astronomer Richard Martin West at the ESO's La Silla Observatory in Chile. The dark Jovian asteroid has a rotation period of 16.4 hours and belongs to the 100 largest Jupiter trojans. It was named after Stentor from Greek mythology, a Herald of the Greeks during the Trojan War.
Orbit and classification
Excerpted from Wikipedia’s “Q147769” article, available under the CC BY-SA 4.0 licence.