29 Amphitrite is one of the biggest S-type asteroids, probably third in diameter after Eunomia and Juno, although Iris and Herculina are similar in size.
It is probably not a fully solid body, since its density is too low for a solid silicate object and much lower than Eunomia or Juno. Its orbit is less eccentric and inclined than those of its bigger cousins - being indeed the most circular of any asteroid found up to that point - and as a consequence it never becomes as bright as Iris or Hebe, especially as it is much farther from the Sun than those asteroids. It can reach magnitudes of around +8.6 at a favorable opposition, but more usually is around the binocular limit of +9.5.
Amphitrite was found by Albert Marth on March 1, 1854. It was the only asteroid he found. It is named after Amphitrite, a sea goddess in Greek mythology.
A moon is suspected based on the lightcurve data. 
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