On the responses to solar X-ray flare and coronal mass ejection

[1] We have used Mars Global Surveyor (MGS) observations for the period 12 to 18 May 2005 to address the effect of X-ray flare and Coronal Mass Ejection (CME) on the Total Electron Content (TEC) of the E region ionosphere of Mars during a violent solar event that occurred on 13 May. Modeling ofE region TEC was also carried out for the time of the flare using the observed X-ray flux. We report that the solar flare caused enhancements in the TEC of Mars by factors of 6 to 10. A response was also observed in the E region plasma frequency of the Earth's ionosphere at nearly same time as the MGS observations. Our results suggest that sporadic E layer plasma frequency and TEC can increase by factors of 3 to 6 during the arrival of a CME at both Earth and Mars.