Hegemone (moon)

Hegemone
Provisional or systematic name	S / 2003 J 8
Central body	Jupiter
Properties of the orbit
Major semi-axis	23,947,000 km
Periapsis	16,092,400 km
Apoapsis	31,801,600 km
eccentricity	0.328
Orbit inclination	155.2 °
Orbital time	739.6 d
Mean orbital velocity	2.35 km / s
Physical Properties
Albedo	0.04
Apparent brightness	22.8 mag
Medium diameter	4 km
Dimensions	4.5 × 10 13 kg
Acceleration of gravity on the surface	≈ 0 m / s 2
Escape speed	≈ 0 m / s
discovery
Explorer	IFA Hawaii
Date of discovery	February 8, 2003

Hegemone (also Jupiter XXXIX) is one of the smaller moons of the planet Jupiter .

discovery

Hegemone was discovered by astronomers at the University of Hawaii on February 8, 2003 , and was initially given the temporary designation S / 2003 J 8. On March 30, 2005 , the moon was officially named Hegemone by the International Astronomical Union (IAU) , after one of the Charites from Greek mythology .

Orbit data

Hegemone orbits Jupiter at a mean distance of 23,947,000 km in 739 days, 14 hours and 24 minutes. The track has an eccentricity of 0.3276. With an inclination of 155.214 °, the orbit is retrograde; that is, the moon moves around the planet against the direction of rotation of Jupiter.

Due to its orbital properties, hegemones are assigned to the Pasiphae group , named after the Jupiter moon Pasiphae .

Physical data

Hegemone has a diameter of about 3 km. Their density is estimated at 2.6 g / cm³. It is probably made up mainly of silicate rock. It has a very dark surface with an albedo of 0.04, i.e. that is, only 4% of the incident sunlight is reflected. Their apparent brightness is 22.9 ^m .

Web links

• IAUC 8088: S / 2003 J 8 March 6, 2003 (discovery)
• MPEC 2003-E15: S / 2003 J 8 March 6, 2003 (discovery)
• MPEC 2003-E24: S / 2003 J 8 March 6, 2003 (rediscovery)
• IAUC 8502: Satellites of Jupiter March 30, 2005 (numbering and naming)

before	Jupiter moons	after that
Pasithee	Hegemone	Mnemes