The Geminid meteoroid stream formation and evolution were studied by the method of nested polynomials. The stream has two layers formed due to differences in orbital parameters of particles ejected from the cometary nucleus before and after perihelion. The shape of the model activity profiles depends on the place where the Earth passes the stream. The importance of observations for calibration of the model is discussed.

The Quadrantid meteor shower is a very regular and prolific meteor shower. As such, one might expect that its parent would be easily recognizable. This is not the case, and numerous comets have been suggested as potential parents. We summarize the situation to date. Recently, an asteroid given the temporary designation 2003 EH1 has been discovered on an orbit that is so similar to that of the Quadrantids that some association between them is probable. The orbit still has some uncertainties and these, together with an orbit that can make fairly close approaches to many planets, make studying its orbital evolution difficult. We have generated, using a statistical model, 500 clones for this body and integrated the motion of these clones back in time for 1000 yr. We find that around ad 1500 the orbit of asteroid 2003 EH1 was very similar to the orbit of the Quadrantids at that date. Further, in 1491, the orbits of a few of these clones were very similar to the orbit of C/1490 Y1 and their sky position also roughly matched that of the comet. Various possibilities are discussed.

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