Are Asteroid 2003 EH1 and Comet C/1490 Y1 Dynamically Related?

Abstract

The orbit of asteroid 2003 EH1 is very similar to the mean orbit of the Quadrantid meteoroid stream so that a close relationship between the two is very likely. It has already been suggested that Comet C/1490 Y1 could be the parent of the Quadrantids. If this is the case, then some relationship between the comet and the asteroid might be expected. The orbit of C/1490 Y1 is based on a short observing arc of about 6 weeks and all the observations were with the naked eye, so that its elements are very poorly determined. Hence, forward integration to determine whether asteroid 2003 EH1 represents the re-discovery of the dormant nucleus of C/1490 Y1 is not feasible. Instead we choose to integrate back in time the orbit of 2003 EH1, which is far better determined, and a family of 3500 clones, all of which are moving on an orbit that is consistent with the present known orbit of 2003EH1. We compare the results primarily with the recorded observations of the comet rather than the orbit of the comet derived by Hasegawa. We find that one clone is consistent with these observations.