Robert sent in the link to https://spaceweather.com … April 14th 2023. Mercury is complicating things. This week it sported a plume of gas flowing behind it – just like a comet. Solar wind and mirco meteorites striking it release sodium gas, a tail that is around 24 million kilometres in length.
The tail was predicted in the 1980s but not actually seen in telescopes until 2001. It has a distinct yellow hue due to the sodium – as well as other elements from the surface of Mercury. People viewing Mercury will probably not notice the tail as it requires a special filter on their lens. The tail waxes and wanes in brightness as it orbits the Sun. The link provides a NASA video from the MESSENGER spacecraft mission that observ ed Mercury’s tail at close range.