Inspired by Chris Hooker's astounding work with the sodium tail of Mercury, I'm still getting to grips with observing it myself. We have a one week window now where the celestial conditions are right, though Mercury is only ever single digit degrees above the horizon when the Sun is out of the way below the horizon, so finding a clear and low western horizon (for the evening apparitions) is part of the struggle, and that annoying cloud band which always seems to form just above the horizon is another, and that is when the sky is clear!

This is a single 45 second exposure made into an animated gif with two versions of the sub, one in its raw state, and the other stretched to highlight a little better the tail, and a rough size marker; I'm not saying I can see 12 arcminutes of tail in this image, it is just a marker of size from the FoV of the set up.

My attempt to image the tail in December 2024 using a longer focal length [and faster] telescope and a DSLR for the then morning apparition revealed evidence of a similar length tail <December 2024 tail>. I am going to try again if the weather allows and use a third telescope, with an even shorter focal length and even faster optics. I also have some work to do on trying to get more images so I can stack them and improve the signal to noise ratio.