Properties of Mlso MK3 White-Light CMEs from 1989-1996
Tuesday, 16 December 2014
Observations low in the solar corona are key to understanding the initiation and propagation of coronal mass ejections (CMEs). Similar to solar magnetographs and total solar irradiance measurements, white-light coronagraph observations are another aspect of Heliophysics that have followed a path comparable to that found in Earth science, where longevity and continuity of measurements lead to new understanding through modeling. Previously we have reported on our efforts to fill the only remaining data gap since 1973 in the CME rate using the Mauna Loa Solar Observatory’s MK3 K-coronameter observations from 1989-1996. The MK3 instrument observed routinely several hours most days beginning in 1980 until it was upgraded to MK4 in 1998. MK3 CMEs detected from 1980-1989 were compared with Solwind and SMM and reported by St. Cyr et al. (1999). Here we provide a preliminary report on the statistical properties of CMEs detected during 1989-1996. Since this period began in solar maximum activity conditions and descended into minimum, we can compare the properties of MLSO MK3 events with CMEs detected by other coronagraphs during similar activity phases.