Orbital motion, nucleus precession, and splitting of periodic Comet Brooks 2

Comet Brooks 2 is the only short-period comet that split and has been observed extensively enough to allow the determination of the time history of the nongravitational parameters, including the transverse component A₂. This information is vital for modeling the nucleus precession, which is of particular interest in this case, as the comet is obviously a fragment of a once larger object. The authors present the results of ten nongravitational orbital solutions based on observations from the apparitions 1889 - 1980. The interpretation, in terms of a variable rate of nucleus precession, makes it possible to determine some of the basic characteristics of the nucleus model, such as the dimensions, oblateness, and rotation period.