So, this is weird: a new insight into the planet Mercury is that it has a big long tail which extends away from the planet, strung outwards by the solar wind (a stream of charged particles shooting away from the Sun in every direction). Comet tails are also due to the solar wind's erosive effect, vaporizing particles & dragging them "down-stream" (i.e., away from the Sun). The tail is long: At 1.6-million miles in length, the streamer of sodium atoms is more than 100 times the planet's radius. Read more here.

Labels: news, planetary geology