Upper limit of ice content at the lunar south pole as revealed by the Earth-based SYISR-FAST bistatic radar system.

An increasing amount of evidence indicates that lunar water ice exists in permanently shadowed regions at the poles and will soon become an important resource for lunar exploration. However, the water ice content and distribution are still uncertain. We report a new 70-cm-wavelength radar image of the lunar south pole obtained by an Earth-based bistatic radar system consisting of the Sanya incoherent scatter radar (SYISR) and the five-hundred-meter aperture spherical radio telescope (FAST).

The intensification of metallic layered phenomena above thunderstorms through the modulation of atmospheric tides.

We present a multi-instrument experiment to study the effects of tropospheric thunderstorms on the mesopause region and the lower ionosphere. Sodium (Na) lidar and ionospheric observations by two digital ionospheric sounders are used to study the variation in the neutral metal atoms and metallic ions above thunderstorms. An enhanced ionospheric sporadic E layer with a downward tidal phase is observed followed by a subsequent intensification of neutral Na number density with an increase of 600 cm in the mesosphere.