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
- Auguste Charlois
- Discovery date
- 18 December 1897
- Pronunciation
- / ˈ n ɛ f ə l iː /
- Named after
- Nephele
- Alternative designations
- 1897 DN
- Minor planet category
- Main belt ( Themis )
- Adjectives
- Nephelean / n ɛ f ɪ ˈ l iː ə n /
- Observation arc
- 113.52 yr (41462 d)
- Aphelion
- 3.67837 AU (550.276 Gm )
- Perihelion
- 2.61178 AU (390.717 Gm)
- Semi major axis
- 3.14507 AU (470.496 Gm)
- Orbital period sidereal
- 5.58 yr (2037.3 d )
- Mean anomaly
- 230.611 °
- Mean motion
- 0° 10 36.152 / day
- Inclination
- 1.82752°
- Longitude of ascending node
- 117.229°
- Argument of perihelion
- 216.161°
- Mean diameter
- 101.900 ± 0.988 km , 94.58 ± 1.03 km
via Wikipedia infobox
Wikidata facts
- Diameter
- 101.9
- Orbital period
- 2038.037283896448
Show 14 more facts
- provisional designation
- A906 HC
- time of discovery or invention
- 1897-12-18
- orbital inclination
- 1.829988468815149
- albedo
- 0.055
- rotation period
- 13.53
- absolute magnitude
- 9.09
- orbital eccentricity
- 0.1717359606074158
- semi-major axis of an orbit
- 3.145882266243591
- periapsis
- 2.605621153292413
- apoapsis
- 3.686143379194768
- longitude of ascending node
- 117.1330544814937
- argument of periapsis
- 218.3776813029436
- mean anomaly
- 110.5353721335525
- time of periapsis
- 2460374.7355288956
Sources (2)
via Wikidata · CC0
~1 min read
Article
431 Nephele is a large Themistian asteroid. It is spectral C-type and is probably composed of carbonaceous material.
It was discovered by Auguste Charlois on 18 December 1897 in Nice.