Assertion: comet | /r/HasProperty | followed by letter
Facets:
Source sentences:
text: Comets are now provisionally designated by the year of their discovery followed by a letter indicating the half-month of the discovery and a number indicating the order of discovery (a system similar to that already used for asteroids).
text: Comets are now designated by the year of their discovery followed by a letter indicating the half-month of the discovery and a number indicating the order of discovery (a system similar to that already used for asteroids), so that the fourth comet discovered in the second half of February 2006, for example, would be designated 2006 D4.