File:000171-asteroid_shape_model_(171)_Ophelia.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
- A. Borrelly
- Discovery date
- 13 January 1877
- Pronunciation
- / oʊ ˈ f iː l i ə / oh- FEE -lee-ə
- Alternative designations
- A877 AB
- Minor planet category
- Main belt ( Themis )
- Adjectives
- Ophelian / ɒ ˈ f iː l i ə n /
- Observation arc
- 122.15 yr (44615 d)
- Aphelion
- 3.5476 AU (530.71 Gm )
- Perihelion
- 2.7175 AU (406.53 Gm)
- Semi major axis
- 3.1326 AU (468.63 Gm)
- Orbital period sidereal
- 5.54 yr (2025.1 d )
- Mean anomaly
- 11.164 °
- Mean motion
- 0° 10 39.972 / day
- Inclination
- 2.5461°
- Longitude of ascending node
- 100.52°
- Argument of perihelion
- 56.849°
- Mean diameter
- 130.808 ± 1.483 km
- Mass
- (1.064 ± 0.535/0.351) × 10 kg
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Ophelia
- Followed by
- 172 Baucis
- Follows
- 170 Maria
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 130.808
- Orbital period
- 2020.659044387783
Show 19 more facts
- discoverer or inventor
- Alphonse Borrelly
- site of astronomical discovery
- Marseille Observatory
- time of discovery or invention
- 1877-01-13
- asteroid spectral type
- C-type asteroid
- orbital inclination
- 2.547010098595385
- albedo
- 0.061
- Commons category
- 171 Ophelia
- provisional designation
- A877 AB
- rotation period
- 6.66535
- absolute magnitude
- 8.63
- orbital eccentricity
- 0.1327832159080217
- semi-major axis of an orbit
- 3.127973570001346
- periapsis
- 2.712631180101272
- apoapsis
- 3.54331595990142
- longitude of ascending node
- 100.4698952818478
- argument of periapsis
- 55.30683795408719
- mean anomaly
- 257.8962489522213
- time of periapsis
- 2461573.602411168
- epoch
- November 21, 2025
Sources (3)
via Wikidata · CC0
~2 min read
Encyclopedic overview
171 Ophelia is a large, dark Themistian asteroid that was discovered by French astronomer Alphonse Borrelly on 13 January 1877. It was named after Ophelia in Shakespeare's Hamlet. This object is orbiting the Sun at a distance of 3.13 AU with an eccentricity of 0.13 and an orbital period of 5.54 years. The orbital plane is inclined at an angle of 2.55° to the plane of the ecliptic.
This asteroid is a member of the Themis family of asteroids that share similar orbital elements. It probably has a primitive composition, similar to that of the carbonaceous chondrite meteorites. The body spans a diameter of 131 km. An analysis of 40 light curves in 2015 suggested it has a convex, elongated shape with one end smaller than the other.
Excerpted from Wikipedia’s “171 Ophelia” article, available under the CC BY-SA 4.0 licence.