Fig. 1From: Concurrent effects of Martian topography on the thermosphere and ionosphere at high northern latitudesA MGS electron density profile as an example illustrating Chapman-α fitting. The gray dots are MGS electron density measurements; the blue solid line is the Chapman-α fitting for the height range of – 10 km to 20 km around the M2 peak. The fitting parameters are labeled, including NmM2, hmM2, and HnBack to article page