NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Robert H. van Gent
Date: 2019 May 20, 09:26 +0000
Nice puzzle.
The url tells me that the location is 19.6662868 north and 87.6527255 west.
When you switch to satellite image and zoom out this reveals that we are on the western coast of Yucatan.
The bright object just above the eastern horizon cannot be the Sun as no stars would then be visible, it has to be the Moon.
The Sun can also be eliminated from the argument that the small top-left inset tells us that the image was captured in December 2016. The Sun should then be in Scorpius, Ophiuchus or Sagittarius,
while the bright object is clearly near or in Gemini. Notice the Hyades and the Pleiades (both in Taurus) near to the Moon.
The Moon, Aldebaran and Capella are roughly in the shape of an equilateral triangle which indicates that the Moon is in Gemini and that the date is December 14, not too long after sunset and less
than a day after Full Moon (December 14, 0:06 UTC).
The distance between the image of the Full Moon and its reflection in the water is nearly equal to the distance between Aldebaran and Capella. The latter distance is about 31 degrees, cf.
http://articles.adsabs.harvard.edu/full/1924MmBAA..24....1.
From this one can estimate that the Moon’s apparent altitude above the horizon is about 15 or 16 degrees. However, this assumes that angular distortions due to the fish-eye projection employed in
this panorama image are small which of course is not the case.
This suggests that the time is about 19:35 local time (December 15, 1:35 UTC).
Switching to the western horizon one immediately recognizes the bright planets Venus (and its reflection in the water) in Capricornus and Mars between Capricornus and Aquarius.
The image of Venus and its reflection in the water suggests that the apparent altitude of Venus above the horizon is about 22 or 23 degrees. This leads to a local time of about 18:45 (0:45 UTC),
some 50 minutes earlier as the time inferred from the Moon’s altitude.
This tells us that the inferred angles should be somewhat smaller and, splitting the difference, that a local time around 19:10 (1:10 UTC) would probably be closer to the truth. The altitudes of
the Moon and Venus would then be about 10 and 17 degrees.
One more planet visible to the naked eye, Uranus, might be on the panorama, near to the zenith. But at an apparent magnitude of only 5.8 it probably did not register in the panorama – at least I
could not spot it.
Rob van Gent
From: NavList@fer3.com <NavList@fer3.com>
On Behalf Of Frank Reed
Sent: Sun 19 May 2019 1:02
To: Gent, R.H. van (Rob) <R.H.vanGent@uu.nl>
Subject: [NavList] Re: Astronomical panorama location and date
Sorry. That was an actual bug. Let's try again...
Here's a 360° panorama accessible in Google "Street View":
astronomical panorama [link fixed]. There are details available from the view that tell us where it is and what month it is. Can we determine the date more accurately? What is that orange ball of light? Are there any planets
visible?? And what time is it? There's a lot of detail here. And fun. :)
Frank Reed
