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I'm originally from a city in Spain which is 40 degrees north, and I used to watch Mercury (naked eye and telescope) every time I had the opportunity, that is, when Mercury was at maximum elongation and there was a clear sky (pretty often thankfuly). Once, I even saw it on a lovely conjunction with Venus, both standing above 5 storey buildings, from the very centre of the city! Amazing.

Three years ago I moved to the Shetland isles, which is 60 degrees north, and because of personal circumstances that are very limiting, I don't think I'll get the chance to go back to Spain at least for a very long time, maybe never. The last time I traveled from there to here (march 2020), Mars Jupiter and Saturn were together in the morning sky, very easily visible just before sunrise the day I left Spain. The next day, in Scotland, I could not see them at all, even though the horizon was cloudless. Stellarium suggested that these three planets would be visible at that place and time. I have seen these three and Venus from here on countless other occasions.

When I was a kid I read somewhere that some astronomers in high latitudes have died without ever seeing Mercury. Is this true?

Not taking into account the weather up here, I wonder if the the ecliptic being less perpendicular to the horizon and therefore having to go through a thicker layer of air, would make it more susceptible to atmospheric refraction to the extent of making Mercury impossible to watch from here. I hope I'm wrong and I get to see Mercury!

Thank you for your time and attention.

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    $\begingroup$ Fascinating question by itself "Have some astronomers in high latitudes died without ever seeing Mercury? Are there any notable and/or documented examples?" I'm not sure if Astronomy SE or History of Science and Mathematics SE would be the better site for it. There is a history tag here but there are a lot more history scholars there. On a separate note, I may end up never seeing 40° latitude again either but went the other direction, which means I may never see snow again nor be able to make an ice telescope $\endgroup$
    – uhoh
    Oct 2 at 22:23
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    $\begingroup$ Mercury will be visible towards the end of the month (October, 2021), in the East and low in the sky (less than 10° in elevation), just before sunrise. $\endgroup$
    – Mick
    Oct 2 at 22:33
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Yes it can be seen, but as the angle of the ecliptic is lower in more Northern Latitudes it is harder to see.

Chris Brown of the Shetland times writes in Feb 2000:

February brings a chance to try and see the elusive planet Mercury. In the week surrounding the 15th Mercury will be setting after the Sun. At best on the 15th at 18:00 it will be just 6 degrees above the horizon. At the same time Mars will be at an altitude of 19 degrees and to the left of Mercury. The time to start looking is just after sunset which on the 15th is about 17:46. It can be helpful to use binoculars to locate Mercury before using your unaided eye or you could do what I do and take along a sharp-eyed friend! No matter if you don't see Mercury this time, as there will be plenty of chances later in the year.

The best time to see it is close to the spring equinox when a Eastern Elongation occurs. In the Northern Hemisphere that means in March or April.

Unfortunately, not all elongations are equal. The best ones can take 10 degrees further from the sun than the worst ones, and (as luck would have it) the next few spring elongations are all less than ideal: Coming up there are

Type Date Elongation Magnitude
Evening 2022 Apr 29 20.6°E +0.5
Evening 2023 Apr 11 19.5°E +0.3
Evening 2024 Mar 24 18.7°E +0.1
Evening 2025 Mar 8 18.2°E -0.1

You should look to the West, and hope for a clear horizon, on or around the date of greatest elongation.

Apart from the bragging rights, Mercury is a poor object for observation. With the naked eye, it is a star caught in the twilight. With a telescope, it is a very small but featureless crescent.

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    $\begingroup$ The bragging rights matter, if it comes to 'all planets in a day' or similar 😀. With photo equipment and narrow band filter Mercury shows a faint sodium tail away from the Sun. $\endgroup$ Oct 3 at 21:49
  • $\begingroup$ @planetmaker How can Mercury's sodium tail be imaged? $\endgroup$
    – uhoh
    Oct 3 at 23:12
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    $\begingroup$ @uhoh Each of those evenings, with observer at 60°N, Stellarium shows Mercury around 10° altitude when the Sun is at -6° altitude. The mornings of 2021-10-25 and 2022-10-08 are almost as favorable. Mercury is near 50% illuminated at those times. $\endgroup$
    – Mike G
    Oct 4 at 17:30
  • $\begingroup$ @MikeG that would be a great answer if posted as such! $\endgroup$
    – uhoh
    Oct 4 at 17:43
  • $\begingroup$ Thanks for the edit! Reversing my vote. $\endgroup$
    – uhoh
    Oct 31 at 23:54
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enter image description hereenter image description here

I am the OP, and I can confirm it, I've just seen Mercury from shetland, 31st october 2021 6 am local time. Apologies for posting this on another answer, but I am so excited and happy about it, almost can't believe it.

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    $\begingroup$ Congratulations! Great news and excellent answer :-) $\endgroup$
    – uhoh
    Oct 31 at 23:52
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    $\begingroup$ @uhoh thank you so much!! $\endgroup$
    – we'll see
    Nov 1 at 7:44

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