Sudden stratospheric warmings (SSWs) are impressive fluid dynamical events in which large and rapid temperature increases in the winter polar stratosphere (∼10–50km) are associated with a complete reversal of the climatological wintertime westerly winds.

Magnetoseismology, a technique of magnetic field diagnostics based on observations of magnetohydrodynamic (MHD) waves, has been widely used to estimate the field strengths of oscillating structures in the solar corona.

The Earth’s upper atmosphere impacts a wide range of technologies, including satellite communication and navigation signals. Specification and forecasting of the upper atmosphere are critical for mitigating these effects.

We consider the vector emissivity of the polarized radiation transfer in a Lambda-type atomic transition, which we recently proposed in order to account for both CRD and PRD contributions to the scattered radiation.

Recent numerical simulations and observations of sunspots show a significant amount of opposite polarity magnetic fields within the sunspot penumbra. Most of the opposite polarity fields are associated with convective downflows.

We report observations of small-scale swirls seen in the solar chromosphere. They are typically 2 Mm in diameter and last around 10 minutes.

The NASA Global-scale Observations of the Limb and Disk (GOLD) instrument is an ultraviolet imager and spectrograph that observes light from the upper-atmosphere of the Earth, in order to infer quantities such as the composition and temperature of the thermosphere.

Three hundred years ago, the Sun began to wake up. For 70 years—from about 1645 to 1715—the Sun had been eerily quiet, with very few sunspots erupting on its surface.