13 Egeria (pronounced /ɨˈdʒɪəriə/ i-JEER-ee-ə, or as in Latin: Ægeria[missing vowel length]) is a large Main belt G-type asteroid.[6]

It was discovered by A. de Gasparis on November 2, 1850, and was named by Urbain J. J. Le Verrier, whose computations led to the discovery of Neptune. Egeria was a goddess (other sources say a nymph) of Aricia, in Italy, and the wife of Numa Pompilius, second king of Rome.

Egeria occulted a star on January 8, 1992. The former's disc was determined to be quite circular (217×196 km).

On January 22, 2008 Egeria occulted another star and this occultation was timed by several observers in New Mexico and Arizona coordinated by the IOTA Asteroid Occultation Program.[7] The data was entered into the OCCULT4 estimation and visualization program written by Dave Herald of Canberra, Australia. The result showed that Egeria presented an approximately circular profile to Earth of 214.8x192 km, well in agreement with the 1992 occultation.

High Water Content

Spectral analysis of Egeria shows it to be unusually high in water content, between 10.5-11.5% water by mass. [8] This makes Egeria a prominent candidate for future water mining ventures.

Notes

1. ^ a b c d e f "JPL Small-Body Database Browser: 13 Egeria". 2008-11-04 last obs. http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=13. Retrieved 2008-11-25.
2. ^ a b Jim Baer (2008). "Recent Asteroid Mass Determinations". Personal Website. http://home.earthlink.net/~jimbaer1/astmass.txt. Retrieved 2008-11-28.
3. ^ "Lightcurves and map data on numbered asteroids N° 1 to 52225". AstroSurf. Archived from the original on 2005-11-27. http://web.archive.org/web/20051127063200/http://www.astrosurf.com/aude-old/map_files/AstVarMAP01-2003.htm. Retrieved 2008-11-03.
4. ^ "Asteroid Data Archive". Planetary Science Institute. http://web.archive.org/web/20060623213811/http://www.psi.edu/pds/archive/astdata04/simps04/diamalb.tab. Retrieved 2008-11-03.
5. ^ apmag 9.71 (2061-Nov-06) to 12.46 (1990-Mar-12) JPL Horizons daily output for 1950 to 2099
6. ^ Rivkin, A. S.; J. K. Davies, S. L. Ellison, L. A. Lebofsky. "High-resolution 2.5–3.5 �M Observations of C-, B- and G-class asteroids." (PDF). http://www.lpi.usra.edu/meetings/LPSC98/pdf/1310.pdf. Retrieved 2008-04-20.
7. ^ Timerson, Brad. "IOTA Asteroid Occultation Results for 2008". http://www.asteroidoccultation.com/observations/Results/index2008.html. Retrieved 2010-01-19.
8. ^ http://www.lpi.usra.edu/meetings/lpsc2002/pdf/1414.pdf

External links

* Orbital simulation from JPL (Java) / JPL Horizons Ephemeris