Correlation of interplanetary scintillation and spacecraft plasma density measurements

Interplanetary scintillation and spacecraft measurements of proton density are observed to be strongly correlated. This result confirms the association between corotating sectors of enhanced scintillation and compression regions located at the interface between fast and slow solar wind streams; it also suggests that scintillation observations provide a means of predicting, several days in advance, the arrival at the Earth, of solar plasma of enhanced density.