Non-periodic comets are seen only once. They are usually on near-parabolic orbits that will not return to the vicinity of the Sun for thousands of years, if ever.
Periodic comets usually have elongated elliptical orbits, and usually return to the vicinity of the Sun after a number of decades.
The official names of non-periodic comets begin with a "C"; the names of periodic comets begin with "P" or a number followed by "P". Comets that have been lost or disappeared have names with a "D".
- List of non-periodic comets
- List of periodic comets
Famous quotes containing the words lists of, lists and/or comets:
“Behold the Atom—I preferred—
To all the lists of Clay!”
—Emily Dickinson (1830–1886)
“Most of our platitudes notwithstanding, self-deception remains the most difficult deception. The tricks that work on others count for nothing in that very well-lit back alley where one keeps assignations with oneself: no winning smiles will do here, no prettily drawn lists of good intentions.”
—Joan Didion (b. 1934)
“I know
No answer to the children’s cry
Of echo’s answer and the man of frost
And ghostly comets over the raised fists.”
—Dylan Thomas (1914–1953)