NavList:

Seeing the actual limb on the horizon at sea is quite a bit more rare than observing the sun rise or set.  this is what makes taking amplitudes of the moon very difficult.  This being said, I have done seen the moon rise twice in the last three years.  The most recent was this summer when I took a moonrise amplitude observation.  The sky and horizon were incredibly clear with no "amplitude clouds." or any other clouds for that matter.  My height of eye was about 30 meters if that is low enough.

 

Jeremy

 

The thread on "An assumption about the moon" reminded me on an other
question related with the moon which I have in my mind already for
quite some time: Is it actually possible for an observer at low
altitudes to see a moonrise or moonset at the apparent horizon ?

Rough estimations which I made some years ago suggested that the
extinction by the mass of atmosphere would be so high that this
shouldn't be possible. The estimation suggested that around 1°
altitude the extinction would be greater than the brightness of the
moon. I saw this supposedly confirmed when watching moonsets over the
Marmara-Sea here in the Istanbul area where the (full) moon just
dimmed out when approaching the horizon. I am however not sure whether
this was only due to a "dirty" atmosphere (haze/smog). The Internet
provides some photos of the moon at landscape horizons but there the
altitude of that landscape horizon is not known. There are also photos
from the heavily flattened moon which astronauts took from space
through parts of the atmosphere. However in those photos the light of
the moon is likely not to pass the densest lowest part of the
atmosphere which there is probably only a very thin stripe over the
earth surface. Do some of you who are occasionally at sea remember
having actually been able to clearly see a moonrise or moonset at the
sea horizon?

Marcel