File:37Fides_(Lightcurve_Inversion).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
- R. Luther
- Discovery date
- October 5, 1855
- Designation
- (37) Fides
- Pronunciation
- / ˈ f aɪ d iː z /
- Named after
- Fides
- Alternative names
- 1925 WH
- Minor planet category
- Main belt
- Adjectives
- Fidean / ˈ f ɪ d i ə n /
- Symbol
- (historical)
- Observation arc
- 167 yr
- Aphelion
- 464.902 million km (3.108 AU )
- Perihelion
- 325.937 million km (2.179 AU)
- Semi major axis
- 395.419 million km (2.643 AU)
- Orbital period sidereal
- 1,569.628 d (4.30 a )
- Mean anomaly
- 303.436°
- Mean motion
- 0° 13 45.84 / day
- Inclination
- 3.071°
- Longitude of ascending node
- 7.267°
via Wikipedia infobox
Wikidata facts
- Instance of
- asteroid
- Named after
- Fides
- Followed by
- 38 Leda
- Follows
- 36 Atalante
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- 108.35
- Mass
- 1.3
- Orbital period
- 1569.472209666668
- Image
- 37Fides (Lightcurve Inversion).png
Show 19 more facts
- discoverer or inventor
- Robert Luther
- site of astronomical discovery
- Düsseldorf-Bilk Observatory
- provisional designation
- A855 TB
- time of discovery or invention
- 1855-10-05
- asteroid spectral type
- S-type asteroid
- orbital inclination
- 3.067627078322873
- albedo
- 0.1826
- Commons category
- 37 Fides
- rotation period
- 7.3335
- absolute magnitude
- 7.34
- orbital eccentricity
- 0.1747141912323353
- semi-major axis of an orbit
- 2.643038375159639
- periapsis
- 2.181262063047597
- apoapsis
- 3.104814687271681
- longitude of ascending node
- 7.235575032161476
- argument of periapsis
- 62.30610171816478
- mean anomaly
- 172.8717335537582
- time of periapsis
- 2460246.8406065293
- epoch
- November 21, 2025
Sources (2)
via Wikidata · CC0
~1 min read
Encyclopedic overview
37 Fides (/ˈfaɪdiːz/) is a large main-belt asteroid. It was discovered by German astronomer Karl Theodor Robert Luther on October 5, 1855, and named after Fides, the Roman goddess of loyalty. Fides was the last of the main-belt asteroids to be assigned an iconic symbol, a Latin cross U+271D ✝ (). 37 Fides is also a S-type asteroid in the Tholen classification system.
Photometric observations of this asteroid at multiple observatories during 1981–82 gave an unusual light curve with three minima and maxima. The curve changed with varying phase angle of the asteroid relative to the viewer and the position of the Sun, indicating the changing influence of shadows cast by surface features. The composite light curve has a best fit period estimate of 7.33 hours. Austrian astronomer Hans Josef Schober has suggested that the multiple minima and maxima during each period may be an indication of a binary nature.
Excerpted from Wikipedia’s “37 Fides” article, available under the CC BY-SA 4.0 licence.