小惑星2＜パラス＞

＊　小惑星2パラス　＊ Pallas, formally designated 2 Pallas, is the second asteroid to have been discovered, by astronomer Heinrich Wilhelm Mattha"us Olbers on March 28, 1802. It was at first considered a planet, as were other early asteroids, until the discovery of many more led to their re-classification. Pallas appears to be the largest irregularly shaped body in the Solar System (that is, the largest body not rounded under its own gravity), and a remnant protoplanet. In 1801, the astronomer Giuseppe Piazzi discovered an object which he initially believed to be a comet. Shortly thereafter he announced his observations of this object, noting that the slow, uniform motion was uncharacteristic of a comet, suggesting it was a different type of object. This was lost from sight for several months, but was recovered later in the year by the Baron von Zach and Heinrich W. M. Olbers after a preliminary orbit was computed by Friedrich Gauss. This object came to be named Ceres, and was the first asteroid to be discovered.

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