Ionospheric Disturbances Triggered by SpaceX Falcon Heavy

Abstract SpaceX launched its Falcon Heavy demonstration mission at 20:45 UT on 6 February 2018 at NASA Kennedy Space Center in Florida. Short‐period northward propagating traveling ionospheric disturbances (TIDs) were observed following the shock waves in the ionospheric total electron content over East Florida‐Atlantic region. These TIDs have the periods of ~6–8 min, amplitude of ~0.05 total electron content unit, horizontal phase velocities of ~420–488 m/s, and horizontal wavelengths of ~164–240 km. They lasted for ~100 min and propagated a long distance of about 1,450 km, exhibiting a nearly coherent wave pattern and near‐constant phase velocity. The theoretical dispersion relation suggests that the short‐period TIDs were likely associated with the ducted gravity waves which became evanescent at altitudes around 170 km. Additional simulations were conducted in the Naval Research Laboratory SAMI3/ESF model using analytical expressions to approximate these gravity waves. Simulations reveal that modulations of the ionospheric electric fields through gravity wave wind dynamo perturbation can lead to weak ionospheric disturbances as observed.