The specification and prediction of density changes in the thermosphere is a key challenge for space weather observations and modeling, because it is one result of complex interactions between the Sun and the terrestrial atmosphere, and also because it is of operational importance for tracking ob

The Sun’s outer atmosphere is heated to temperatures of millions of degrees, and solar plasma flows out into interplanetary space at supersonic speeds. This paper reviews our current understanding of these interrelated problems: coronal heating and the acceleration of the ambient solar wind.

The NCAR Whole Atmosphere Community Climate Model (WACCM), with a quasi-uniform horizontal resolution of $\sim$25km and a vertical resolution of 0.1 scale height, produces large horizontal winds and vertical shears maximizing in the mesosphere and lower thermosphere (MLT), similar to those found

In this NASA-led study, we report the concept of using near-real time observations from a coronagraph to provide early warning of a fast coronal mass ejection (CME) and the possible onset of a solar energetic particle (SEP) event.