The equilibrium tide-generating forces in the lunar orbital plane of a planet of radius R are calculated for the case of N moons of mass Mi orbiting the planet at instantaneous polar coordinates (Di, αi). For the case of a single moon, there are only two high tides. For the case of two moons, it is found that there can exist a critical lunar orbital distance at which two high tides become unsta...

Introduction: The lunar surface is covered with a thick layer of micron/sub-micron size dust grains formed by meteoritic impact over billions of years. The fine dust grains are levitated and transported on the lunar surface, as indicated by the transient dust clouds observed over the lunar horizon during the Apollo 17 mission [1-5] Theoretical models suggest that the dust grains on the lunar su...

This December marks 40 years since Gene Cernan and Harrison “Jack” Schmitt of Apollo 17 left the lunar surface and returned safely to Earth. This anniversary has been given additional poignancy by the death earlier this year of Neil Armstrong, the first man to set foot on the Moon with Apollo 11 in July 1969. The history of the Apollo project, and its geopolitical motivation within the context ...

It seems that the wind shear theory is accepted for the explanation of sporadic E at mid and low latitudes. Some examples from Arecibo are displayed to show this. The e€ect of lunar tides should then modify the wind-shear theory in a manner that yields the observed features of the lunar tide in the critical frequency foEs and the height h¢Es of the sporadic E. This is shown to imply that the ph...

The Moon has long been thought to be highly depleted in volatiles such as water, and indeed published direct measurements of water in lunar volcanic glasses have never exceeded 50 parts per million (ppm). Here, we report in situ measurements of water in lunar melt inclusions; these samples of primitive lunar magma, by virtue of being trapped within olivine crystals before volcanic eruption, did...

Microcrystals of coesite and stishovite were discovered as inclusions in amorphous silica grains in shocked melt pockets of a lunar meteorite Asuka-881757 by micro-Raman spectrometry, scanning electron microscopy, electron back-scatter diffraction, and transmission electron microscopy. These high-pressure polymorphs of SiO(2) in amorphous silica indicate that the meteorite experienced an equili...

Introduction: Lunar domes are smooth low features similar to low terrestrial shield volcanoes. They were formed during the terminal phases of lunar eruptions and mostly occur in the maria. A few domes have been reported in the highlands, but these are usually difficult to observe because of the brightness and ruggedness of the surrounding terrain. According to [1,2], constructional volcanic fea...

The Jet Propulsion Laboratory (JPL) is developing the All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) as part of NASA’s Exploration Systems Mission Directorate, Exploration Technology Development Program (ETDP). The program develops technologies for surface mobility and equipment handling, human-system interaction, and lunar surface system repair, and constructs dexterous robots and...

INTRODUCTION Lunar calendars, publishing recommendations for daily life, are gaining more and more attention in Germany, where 10.5% of the population believe in lunar effects on disease. A widespread and often heard belief is that a full moon has the most negative effects on surgical outcome. The present study evaluates the effects of lunar phase on perioperative complications in total hip art...

Many people see a human face or animals in the pattern of the maria on the moon. Although the pattern corresponds to the actual variation in composition of the lunar surface, the culture and environment of each society influence the recognition of these objects (i.e., symbols) as specific entities. In contrast, a convolutional neural network (CNN) recognizes objects from characteristic shapes i...