|Discovered by||C. D. Perrine|
|Discovery time||January 2, 1905|
|Avg. distance from the center of its orbital path||11,740,00 km (0.07810 AU)|
|How egg-shaped its orbit is
|How long it takes to complete an orbit||259.64 d (0.708 a)|
|Average speed||3.27 km/s|
|Angle above the reference plane
|26.63° (to the ecliptic)
30.66° (to Jupiter's equator)
|What it orbits||Jupiter|
|Size and Other Qualities|
|Average distance from its center to its surface||43 km|
|Area of its surface||~23,200 km2|
|Volume inside it||~333,000 km3|
|Average density||2.6 g/cm3 (assumed)|
|Gravity at its surface||~0.031 m/s2 (0.003 g)|
|Slowest speed able to escape into space
|How long it takes to turn around one time
(in relation to the stars)
|~0.5 d (12 h)|
|How much light it reflects||0.04 (assumed)|
|Avg. surface temp.||~124 K|
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[change | change source]
References[change | change source]
- Perrine, C. D. (1905 February 27). "Satellites of Jupiter". Harvard College Observatory Bulletin 178. http://adsabs.harvard.edu//full/seri/BHarO/0178//0000001.000.html.
- Perrine, C. D. (1905). "The Seventh Satellite of Jupiter". Publications of the Astronomical Society of the Pacific 17 (101): 62–63. http://adsabs.harvard.edu//full/seri/PASP./0017//0000062.000.html.
- Jacobson, R. A. (2000). "The orbits of outer Jovian satellites". Astronomical Journal 120: 2679-2686. .
- Marsden, B. G. (7 October 1974). "Satellites of Jupiter". IAUC Circular 2846. http://cfa-www.harvard.edu/iauc/02800/02846.html.
- Payne-Gaposchkin, Cecilia; Katherine Haramundanis (1970). Introduction to Astronomy. Englewood Cliffs, N.J.: Prentice-Hall. .
Other websites[change | change source]