Eirene (moon)
Eirene | |
---|---|
Provisional or systematic name | S / 2003 J 5 |
Central body | Jupiter |
Properties of the orbit | |
Major semi-axis | 23,668,000 km |
Periapsis | 18,422,000 km |
Apoapsis | 28,914,000 km |
eccentricity | 0.222 |
Orbit inclination | 163.1 ° |
Orbital time | 743.88 d |
Mean orbital velocity | 2.31 km / s |
Physical Properties | |
Albedo | 0.04 |
Apparent brightness | 22.4 mag |
Medium diameter | ≈ 4 km |
Dimensions | ≈ 9.0 · 10 13 kg |
Medium density | 2.6 g / cm 3 |
Acceleration of gravity on the surface | ≈ 0.0015 m / s 2 |
Escape speed | ≈ 2.5 m / s |
discovery | |
Explorer |
University of Hawaii |
Date of discovery | February 6, 2003 |
Eirene (also Jupiter LVII ) is one of the smaller moons of the planet Jupiter .
discovery
Eirene was discovered by astronomers at the University of Hawaii on February 6, 2003 and was given the provisional designation S / 2003 J 5. On August 23, 2019, she was named by the International Astronomical Union after Eirene , the goddess of peace in Greek mythology .
Orbit data
Eirene orbits Jupiter at an average distance of 23.668 million km in just 744 days. The track has an eccentricity of 0.222. With an inclination of 163.1 °, the orbit is retrograde ; that is, the moon moves around the planet against the direction of rotation of Jupiter.
Due to its orbit characteristics, Eirene is assigned to the Carme Group , named after the Jupiter moon Carme .
Physical data
Eirene has a diameter of about 4 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 22.4 m .
Web links
- IAUC 8087: Satellites of Jupiter March 4, 2003 (discovery)
- MPEC 2003-E11: S / 2003 J 1, 2003 J 2, 2003 J 3, 2003 J 4, 2003 J 5, 2003 J 6, 2003 J 7 March 4, 2003 (discovery)
- MPEC 2017-L21: S / 2003 J 5 June 2nd, 2017 (rediscovery)
Individual evidence
- ↑ The results are in! Jovian moon-naming contest winners announced. Carnegie Institution for Science, August 23, 2019; accessed August 28, 2019 .
before | Jupiter moons | after that |
S / 2011 J 2 | Eirene (moon) |
Philophrosyne (moon) |