91 Aegina

Also known as (91) Aegina, Aegina

main-belt asteroid

In the Vinony graph

Within Vinony's link graph, 91 Aegina is referenced by 11 other articles, and connects out to asteroid belt, Édouard Stephan and France.

It sits within the topics Astronomical objects discovered in 1866, Background asteroids and Ch-type asteroids (SMASS).

Its subject is documented across 46 Wikipedia language editions.

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: Édouard Stephan
Discovery date: 4 November 1866
Pronunciation: / ɪ ˈ dʒ aɪ n ə /
Named after: Aegina
Minor planet category: Main belt
Adjectives: Aeginetan / iː dʒ ɪ ˈ n iː t ə n /
Aphelion: 428.453 Gm (2.864 AU )
Perihelion: 346.826 Gm (2.318 AU)
Semi major axis: 387.640 Gm (2.591 AU)
Orbital period sidereal: 1,523.536 d (4.171 yr)
Average orbital speed: 18.45 km/s
Mean anomaly: 183.458°
Inclination: 2.109°
Longitude of ascending node: 10.806°
Argument of perihelion: 73.371°
Dimensions: 109.8 km
Mass: 1.4 × 10 kg
Equatorial surface gravity: 0.0307 m/s

via Wikipedia infobox

Wikidata facts

Instance of: asteroid
Named after: Aegina
Followed by: 92 Undina
Follows: 90 Antiope
Parent body: Sun
Minor-planet group: asteroid belt
Diameter: 103.402
Mass: 1.4
Orbital period: 1522.761591603033

Show 19 more facts

discoverer or inventor: Édouard Stephan
site of astronomical discovery: Marseille Observatory
time of discovery or invention: 1866-11-04
albedo: 0.048
Commons category: 91 Aegina
provisional designation: A866 VA
rotation period: 6.025
asteroid spectral type: C-type asteroid
absolute magnitude: 9.13
orbital eccentricity: 0.1081827691424325
semi-major axis of an orbit: 2.590333356799024
periapsis: 2.310103921258493
apoapsis: 2.870562792339555
orbital inclination: 2.102439955361636
longitude of ascending node: 10.3871304109186
argument of periapsis: 74.31136191618903
mean anomaly: 14.3894626546149
time of periapsis: 2460939.6341081825
epoch: November 21, 2025

Sources (2)

via Wikidata · CC0

~2 min read

Encyclopedic overview

91 Aegina (from Latin Aegīna, Aegīnēta) is a large main-belt asteroid. It was discovered by French astronomer Édouard Jean-Marie Stephan on 4 November 1866. It was his second and final asteroid discovery. The first was 89 Julia. The asteroid's name comes from Aegina, a Greek mythological figure associated with the island of the same name.

This body is orbiting the Sun with a period of 4.17 years and an eccentricity of 0.105. The orbit of this object brings it to within 4.9 Gm of the dwarf planet Ceres, and the resulting gravitational interaction has been used to produce mass estimates of the latter. The cross-section size of the asteroid is 110 km and it has a rotation period of six hours. The surface coloring of 91 Aegina is very dark and this C-type asteroid has probably a primitive carbonaceous composition. Observation of absorption bands at wavelengths of 0.7 and 3 μm indicate the presence of hydrated minerals and/or ice grains on the surface.

Excerpted from Wikipedia’s “91 Aegina” article, available under the CC BY-SA 4.0 licence.