what is it about?
It  is the branch of astronomy that deals with the motions of objects in outer space.
Celestial mechanics
 is the branch of astronomy that deals with the motions of objects in outer space. 
an isosceles triangle has two sides of equal length UNANSWERABLE how did it gat the name? "Isosceles" is made from the Greek roots "isos" (equal) and "skelos" (leg). how can one find it's area? The same area formula can also be derived from Heron's formula for the area of a triangle from its three sides. where all can it be applied? Celestial mechanics
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Celestial mechanics [SEP] Introduction
Celestial mechanics is the branch of astronomy that deals with the motions of objects in outer space. Historically, celestial mechanics applies principles of physics (classical mechanics) to astronomical objects, such as stars and planets, to produce ephemeris data.