Megaclite

Megaclite /mɛɡəˈklaɪtiː/, also known as Jupiter XIX, is one of Jupiter's smallest and outermost natural satellites.

Megaclite

Megaclite imaged by the Canada-France-Hawaii Telescope in December 2001
Discovery[1]
Discovered by	Scott S. Sheppard David C. Jewitt Yanga R. Fernandez Eugene A. Magnier
Discovery site	Mauna Kea Observatory
Discovery date	25 November 2000
Designations
Designation	Jupiter XIX
Pronunciation	/mɛɡəˈklaɪtiː/
Named after	Μεγακλειτή Megaclītē
Alternative names	S/2000 J 8
Adjectives	Megaclitean /ˌmɛɡəklɪˈtiːən/
Orbital characteristics[2]
Epoch 2026-01-01
Observation arc	16.26 yr (5,938 days)
Periapsis	13.1 million km
Apoapsis	33.80 million km
Semi-major axis	23.5 million km
Eccentricity	0.440
Orbital period (sidereal)	–734.6 days
Mean anomaly	256°
Mean motion	0° 28m 54.732s / day
Inclination	147.7° (to ecliptic)
Longitude of ascending node	22.8°
Argument of perihelion	32.4°
Satellite of	Jupiter
Group	Pasiphae group
Physical characteristics[3]
Mean diameter	≈ 6 km
Albedo	0.04 (assumed)
Apparent magnitude	21.7[4]
Absolute magnitude (H)	15.0[5]

Discovery and Naming

It was discovered by a team of astronomers from the University of Hawaiʻi led by Scott S. Sheppard in 2000, and given the temporary designation S/2000 J 8.^[6][1][7]

It was named in October 2002 after Megaclite, mother by Zeus (Jupiter) of Thebe and Locrus in Greek mythology. It was initially erroneously named Magaclite, which was corrected in November 2002.^[8][9] Despite this correction, some earlier research still referred to the moon as Magaclite.^[10]

Orbit

Megaclite orbits Jupiter (on average at 23.5 million km) on a high-eccentricity (0.440) and high-inclination (148° to ecliptic) retrograde orbit. The orbital elements are continuously changing due to solar and planetary perturbations.

It belongs to the Pasiphae group, a group of retrograde moons of Jupiter with semi-major axes spread over 22–25 million km, inclinations between 141° and 158°, and higher eccentricities between 0.22 and 0.44.

Animation of Megaclite's orbit from 1900 to 2100

Polar view

Equatorial view

  Jupiter ·   Megaclite

Physical characteristics

Megaclite's estimated diameter is 6 kilometers, assuming an albedo of 4%.

While Pasiphae belongs to the grey color class (B−V=0.74, V−R=0.38), Megaclite falls under the light red color class (B−V=0.94, V−R=0.41 ), similarly to Callirrhoe and Sinope.^[10]

Origin

Megaclite probably did not form near Jupiter but was captured by Jupiter later. Megaclite is believed to be a fragment from a captured asteroid along with other Pasiphae group satellites.^[11][12]

However, it falls into a different color class than Pasiphae and could therefore have been captured by Jupiter independently of the Pasiphae group.