  A new dataset of summed neutral N2 and O number density profiles, spanning
altitudes between 150 and 400 km, and observed during Northern Winter from 2010
through 2016 is presented. The neutral density profiles are derived from solar
occultation measurements made by the 0.1-20 nm Zr channel on the LYRA
instrument onboard PROBA2. The climatology derived from the vertical profiles
is consistent with that predicted by the NRLMSISE-00 model, and the systematic
error and random uncertainty of the measurements is less than 13% and 6%,
respectively. The density profiles are used to characterize the response of
thermospheric density to solar EUV irradiance variability. Peak correlation
coefficients between neutral density and EUV irradiance occur near 300 km at
the dusk terminator and 220 km at the dawn terminator. The sensitivity of
thermospheric temperature to EUV irradiance decreases with altitude above 300
km at both terminators.
