Elara (moon) facts for kids
Elara near the glare of bright Jupiter
|
|
| Discovery | |
|---|---|
| Discovered by | C. D. Perrine |
| Discovery date | January 5, 1905 |
| Orbital characteristics | |
|
Mean orbit radius
|
11,740,000 km (0.07810 AU) |
| Eccentricity | 0.22 |
| 259.64 d (0.708 a) | |
|
Average orbital speed
|
3.27 km/s |
| Inclination | 26.63° (to the ecliptic) 30.66° (to Jupiter's equator) |
| Satellite of | Jupiter |
| Physical characteristics | |
|
Mean radius
|
43 km |
| ~23,200 km2 | |
| Volume | ~333,000 km3 |
| Mass | 8.7×1017 kg |
|
Mean density
|
2.6 g/cm3 (assumed) |
| ~0.031 m/s2 (0.003 g) | |
| ~0.052 km/s | |
|
Sidereal rotation period
|
~0.5 d (12 h) |
| Albedo | 0.04 (assumed) |
| Temperature | ~124 K |
| 16.3 | |
Elara is a non-spherical moon of Jupiter. It was found by Charles Dillon Perrine at Lick Observatory in 1905 and is named after the mother by Zeus of the giant Tityus.
Elara did not get its present name until 1975; before then, it was simply known as Jupiter VII. It was sometimes called "Hera" between 1955 and 1975.
Elara belongs to the Himalia group, five moons orbiting between 11,000,000 and 13,000,000 km from Jupiter at an inclination of about 27.5°. Its orbital elements are as of January 2000. They are changing a lot due to Solar and planetary perturbations.
New Horizons encounter
In February and March 2007, the New Horizons spacecraft to Pluto made a number of pictures of Elara, culminating in photos from a distance of five million miles.
Images for kids
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Elara observed by the Wide-field Infrared Survey Explorer (WISE) spacecraft in 2014
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Elara imaged by the LORRI instrument aboard New Horizons
See also
In Spanish: Elara (satélite) para niños
