Some early results… despite the poor weather I managed to get a few spectra on the night on 12/13 Dec. Unfortunately as most were fairly early on, the radiant was low and the dispersion angle was quite poor. I was hoping it would stay clear until the radiant was higher with the gratings better orientated, so much for that idea….
Anyway got one decent resolution, partial spectrum showing the Mg and Na lines with some weaker Fe and ca lines.
This graph shows the relatively stronger Mg emission (~517nm) compared with Na (~589nm). This is a flux instrument corrected spectrum to try and accurately portray the Mg/Na difference.
The reduced Na line is attributed to loss of the volatiles due to the orbit of Phaethon 3200. It is interesting to compare with previous observations.
This is a spectrum multiplot from 2017. Although spanning a greater wavelength range it can be seen that the relative strengths of the Mg and Na lines are broadly consistent with this years observations.