Assertion: comet's orbit | /r/HasProperty | long elliptical
Facets:
Source sentences:
text: Due to its long elliptical orbit, it is estimated that Donati's Comet will not be seen passing by Earth again until the 4th millennium: Asten calculated a perihelion date of September 3738 and an orbital period of 1880 years[citation needed], and Hill suggested September 3808 and a period of 1950 years[citation needed].