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
- Harvard College Obs.
- Discovery site
- Agassiz Stn.
- Discovery date
- 2 February 1975
- Named after
- Fred L. Whipple , (American astronomer)
- Alternative designations
- 1975 CA · 1932 AD, 1950 LH · 1962 SH, 1970 EC 1 · 1971 KD 1 , 1971 KN · A916 AD
- Minor planet category
- main-belt · ( outer )
- Observation arc
- 54.50 yr (19,907 days)
- Aphelion
- 3.2556 AU
- Perihelion
- 2.8656 AU
- Semi major axis
- 3.0606 AU
- Orbital period sidereal
- 5.35 yr (1,956 days)
- Mean anomaly
- 18.583 °
- Mean motion
- 0° 11 2.76 / day
- Inclination
- 6.5587°
- Longitude of ascending node
- 263.80°
- Argument of perihelion
- 179.82°
- Mean diameter
- 32.57 ± 0.43 km , 33.83 km (derived) , 33.87 ± 1.3 km , 36.34 ± 0.66 km , 37.481 ± 0.250 km , 40.431 ± 0.471 km
- Synodic rotation period
- 5.78 ± 0.03 h , 6.953 ± 0.003 h
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Fred Lawrence Whipple
- Followed by
- (1941) Wild
- Follows
- Q146192
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 37.481
- Orbital period
- 1957.486876374626
- Image
- 001940-asteroid shape model (1940) Whipple.png
Show 17 more facts
- discoverer or inventor
- Harvard College Observatory
- provisional designation
- A916 AD
- site of astronomical discovery
- Oak Ridge Observatory
- time of discovery or invention
- 1975-02-02
- orbital eccentricity
- 0.0609906673961168
- orbital inclination
- 6.539331498556402
- periapsis
- 2.87565554353145
- apoapsis
- 3.249215517243261
- semi-major axis of an orbit
- 3.062435530387356
- mean anomaly
- 204.1028598025969
- longitude of ascending node
- 263.5632353491666
- argument of periapsis
- 186.0716134859505
- absolute magnitude
- 11.36
- albedo
- 0.06
- rotation period
- 6.953
- time of periapsis
- 2461848.185016669
- epoch
- November 21, 2025
Sources (3)
via Wikidata · CC0
~3 min read
Encyclopedic overview
1940 Whipple (prov. designation: 1975 CA) is a carbonaceous background asteroid from the outer region of the asteroid belt, approximately 35 kilometers (22 miles) in diameter. It was discovered on 2 February 1975, by the Harvard College Observatory at its George R. Agassiz Station near Harvard, Massachusetts, in the United States, and named after astronomer Fred Whipple.
Classification and orbit
Excerpted from Wikipedia’s “Q146210” article, available under the CC BY-SA 4.0 licence.