Alcyone

Discovery

Discovery date: Jan. 15, 3505

Orbital characteristics

Semi-major axis: 425489 km
Eccentricity: 0.001
Orbital period: 1.938 d
Average orbital speed: 16.0 km/s
Inclination: 0.15°
Satellite of: Paraterea

Physical characteristics

Radius: 1277.7 km
Surface area: 20515840 km²
Mass: 3.9E+22 kg
Density: 4.44 g/cm³
Surface gravity: 1.59 m/s²
Escape velocity: 2.02 km/s
Rotation period: 1.938 d
Surface temperature: -172°C | -168°C | -166°C

Orbit

Alcyone orbits around Paraterea in a nearly circular orbit, with an orbital period of approximately 1.9 days. Alcyone's orbital eccentricity is close to zero, indicating its stable orbit. The inclination of the orbit to Paraterea is about 0.15°, making its motion almost in the equatorial plane of the planet.

Surface

Alcyone's surface is covered with many craters, indicating its long history of collisions with asteroids. Cracks and fractures in the moon's surface indicate its past tectonic activity. Volcanic processes may have played a role in its formation, although no active volcanoes have been observed. The surface layer consists mostly of water ice with a mixture of rocks, which gives the moon its dark color.

Atmosphere

Alcyone has a fragile atmosphere consisting mainly of water vapor with methane and ammonia. The pressure on the moon's surface is extremely low, making the atmosphere unnoticeable

These artifacts were so unusual and mysterious that scientists from all planets rushed to study them. Their structure was so complex and mysterious that the unraveling of each element opened new horizons. And now, it would seem, a simple touch to these gifts gave an understanding that pierced the fabric of reality, allowing to look beyond the ordinary.