good agreement with the ejection model by @ma02. While the eccentricity, the inclination and angular elements of the MON lie within the cometary clones’ range, the derivation of the radial and normal components of the velocity vector are ambiguous, following equations by @pec97. On the other hand, a difference in the inclination, the eccentricity and angular elements of the NOO could not be explained by the direct ejection of the particles into current orbits, but only by the following orbital evolution.

   shower   method   a \[AU\]   $-\Delta\,v_{t}$ \[m/s\]
  -------- -------- ---------- --------------------------
    MON      mean      8.8             $104\pm8$
             peak      6.5             $117\pm8$
            range      3-17             $50-145$
    NOO      mean     11.36             $90\pm8$
             peak      6.5             $117\pm8$
            range      2-17             $50-150$

  : The transversal component of the meteoroid ejection velocity derived from the the difference of the semimajor axis of meteor showers and the parent comet. The range of cometary semimajor axis lies within $a\subset(26;29)$AU.[]{data-label="t4"}

Conclusions
===========

We demonstrated that the December Monocerotids and November Orionids obtained from the SonotaCo database of 3 year observations (2007-2009) have most likely a common origin and come from the comet C/1917 F1 Mellish. The common origin is supported by their similar orbital characteristics, the activity, physical properties assumed from the beginning, and the 