The moon has a tail, and Earth wears it like a scarf once a month

"In the meantime, we'll have to be content with the knowledge that, once a month, our companion in the sky showers Earth with a pinch of cosmic pixie dust."

Very cool and interesting :) The link in the report ( provided as this plain language summary:

"Plain Language Summary
Once a month, at the time of new moon a small, diffuse spot of light appears in the sky opposite the Sun. This spot is about five times the diameter of the full moon, and is 50 times fainter than can be seen with the unaided eye. The spot is reflected light from millions of sodium atoms that two days earlier were on the surface of the Moon. These atoms were liberated from the Moon's surface by meteoroid impacts, the solar wind and photons. Once free of the lunar surface, the atoms are pushed by light pressure into a long comet‐like tail. When this very diffuse cloud of sodium atoms encounters the Earth's gravity, it is “focused” into a region of enhanced density becoming visible to sensitive cameras equipped with filters tuned to the orange light emitted by sodium near 589.3 nm. All‐Sky‐Imager data were analyzed to see how the brightness of this spot varies over time, with a goal of finding a correlation with one (or more) of the above mentioned source processes. A correlation was found between the brightness of the sodium spot and the meteor rate observed at Earth using meteor radar data."

50 times fainter than the unaided eye suggest an apparent magnitude + 10.2 or so where people could see down to +6.0 or so on the scale. New Moon is tomorrow (13-March) at 1021 UT. Because this tail is *focused* by Earth's gravity, looks like another confirmation of Newton here and the heliocentric solar system view of the motion of the Moon around the spherical Earth :)
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