File:446_Aeternitas.png · Wikimedia Commons · See Wikimedia Commons
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
- M. F. Wolf , A. Schwassmann
- Discovery date
- 27 October 1899
- Pronunciation
- / iː ˈ t ɜːr n ɪ t æ s /
- Named after
- Aeternitas
- Alternative designations
- 1899 ER
- Minor planet category
- Main belt
- Observation arc
- 116.23 yr (42452 d)
- Aphelion
- 3.14078 AU (469.854 Gm )
- Perihelion
- 2.43222 AU (363.855 Gm)
- Semi major axis
- 2.78650 AU (416.854 Gm)
- Orbital period sidereal
- 4.65 yr (1699.0 d )
- Mean anomaly
- 83.3875 °
- Mean motion
- 0° 12 42.811 / day
- Inclination
- 10.6270°
- Longitude of ascending node
- 42.0823°
- Argument of perihelion
- 279.496°
- Dimensions
- 45.40 ± 3.2 km
- Synodic rotation period
- 15.7413 h (0.65589 d )
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Aeternitas
- Followed by
- Q154218
- Follows
- Q154133
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 53.562
- Orbital period
- 1699.905253126125
Show 19 more facts
- discoverer or inventor
- Friedrich Karl Arnold Schwassmann
- site of astronomical discovery
- Heidelberg-Königstuhl State Observatory
- provisional designation
- A899 UB
- time of discovery or invention
- 1899-10-27
- orbital inclination
- 10.61499923838179
- Commons category
- 446 Aeternitas
- albedo
- 0.317
- rotation period
- 15.7413
- asteroid spectral type
- A-type asteroid
- absolute magnitude
- 8.86
- orbital eccentricity
- 0.1245964148145825
- semi-major axis of an orbit
- 2.787517009030223
- periapsis
- 2.440202383470389
- apoapsis
- 3.134831634590057
- longitude of ascending node
- 42.01312470135303
- argument of periapsis
- 279.3408003632408
- mean anomaly
- 83.68744059673709
- time of periapsis
- 2460605.331333636
- epoch
- November 21, 2025
Sources (2)
via Wikidata · CC0
~1 min read
Encyclopedic overview
446 Aeternitas is a main belt asteroid. It was discovered by Max Wolf and A. Schwassmann on 27 October 1899 in Heidelberg. It is classified as an A-type asteroid. The asteroid is roughly 45 km in diameter and has a high albedo.
References
Excerpted from Wikipedia’s “446 Aeternitas” article, available under the CC BY-SA 4.0 licence.