File:174Phaedra_(Lightcurve_Inversion).png · Wikimedia Commons · See Wikimedia Commons
OverviewAI-generated
174 Phaedra is an S-type asteroid located in the asteroid belt, orbiting the Sun. It was discovered by James Craig Watson at the Detroit Observatory on September 2, 1877. The object carries the provisional designation A877 RA and is named after Phaedra. In the sequence of minor planets, it follows 173 Ino and is followed by 175 Andromache.
Physically, 174 Phaedra has a diameter of 64.849 kilometers and an albedo of 0.169. Its rotation period is 5.744 hours, and its absolute magnitude is 8.4. Orbital parameters include a semi-major axis of 2.858213489912945 AU, an eccentricity of 0.1453987165266226, and an inclination of 12.13 degrees. The periapsis is 2.442632916920525 AU, while the apoapsis is 3.273794062905366 AU.
Synthesized by Vinony from 35 facts across 4 sources: Wikidata, NASA, Jpl Sbdb, Vinony graph. Generated from structured data (not the Wikipedia text) and checked against those facts — may still contain errors.
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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
Small body data
174 Phaedra (A877 RA)
- Orbit class
- Main-belt Asteroid
- Diameter
- 64.849 km
- Albedo
- 0.169
- Rotation period
- 5.744 h
- Absolute magnitude
- 8.390 H
- Earth MOID
- 1.460 AU
via NASA/JPL Small-Body Database
Key facts
- Discovered by
- J. C. Watson
- Discovery date
- 2 September 1877
- Pronunciation
- / ˈ f iː d r ə /
- Alternative designations
- A877 RA
- Minor planet category
- Main belt
- Observation arc
- 138.61 yr (50629 d)
- Aphelion
- 3.2658 AU (488.56 Gm )
- Perihelion
- 2.4572 AU (367.59 Gm)
- Semi major axis
- 2.8615 AU (428.07 Gm)
- Orbital period sidereal
- 4.84 yr (1768.0 d )
- Mean anomaly
- 330.70 °
- Mean motion
- 0° 12 13.032 / day
- Inclination
- 12.124°
- Longitude of ascending node
- 327.69°
- Argument of perihelion
- 289.08°
- Earth moid
- 1.47439 AU (220.566 Gm)
- Jupiter moid
- 1.99981 AU (299.167 Gm)
- Mean radius
- 34.62 ± 2.2 km
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Phaedra
- Followed by
- 175 Andromache
- Follows
- 173 Ino
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 64.849
- Orbital period
- 1764.982581904922
- Image
- 174Phaedra (Lightcurve Inversion).png
Show 19 more facts
- discoverer or inventor
- James Craig Watson
- site of astronomical discovery
- Detroit Observatory
- time of discovery or invention
- 1877-09-02
- asteroid spectral type
- S-type asteroid
- orbital inclination
- 12.10491967224068
- albedo
- 0.169
- Commons category
- 174 Phaedra
- provisional designation
- A877 RA
- rotation period
- 5.744
- absolute magnitude
- 8.4
- orbital eccentricity
- 0.1453987165266226
- semi-major axis of an orbit
- 2.858213489912945
- periapsis
- 2.442632916920525
- apoapsis
- 3.273794062905366
- longitude of ascending node
- 327.2649436806221
- argument of periapsis
- 291.0212044718528
- mean anomaly
- 301.2052487409334
- time of periapsis
- 2461288.7547552213
- epoch
- November 21, 2025
Sources (2)
via Wikidata · CC0
~1 min read
Encyclopedic overview
174 Phaedra is a sizable, rocky main belt asteroid that was discovered by Canadian-American astronomer James Craig Watson on September 2, 1877, and named after Phaedra, the tragic lovelorn queen in Greek mythology.
The asteroid is orbiting the Sun with a period of 4.84 years and an eccentricity of 0.14. Lightcurve data obtained from Phaedra indicates a rather irregular or elongated body. It has a cross-section size of ~35 km. Photometric observations of this asteroid at the Shadowbox Observatory in Carmel, Indiana, during 2009 gave a light curve with a period of 4.96 ± 0.01 hours. This is consistent with previous studies in 1977, 1988, and 2008. The asteroid's pole of rotation lies just 5–16° away from the plane of the ecliptic.
Excerpted from Wikipedia’s “174 Phaedra” article, available under the CC BY-SA 4.0 licence.