[REL] Nautical Almanac for 1941 - 1945

[DavyJonesFootlocker]

Did someone mentioned Pin-up Girls? I pinned one to a wall but she just hung there.

[Nuc]

I was cruising on the surface and saw the scene below. I check the Almanac from this download and sure enough on this date (Dec 18, 1941) moonset was to be 26 minutes after sunset. My question is; Is this an observable situation in the real world or would the sun's glare prevent seeing the moon?

[swdw]

Originally Posted by Nuc

I was cruising on the surface and saw the scene below. I check the Almanac from this download and sure enough on this date (Dec 18, 1941) moonset was to be 26 minutes after sunset. My question is; Is this an observable situation in the real world or would the sun's glare prevent seeing the moon?

You mean like this?
http://www.igougo.com/travelcontent/...PhotoID=328270

[kylesplanet]

Originally Posted by swdw

You mean like this?
http://www.igougo.com/travelcontent/...PhotoID=328270

Cool pic swdw

[Sailor Steve]

Originally Posted by Kapitan_Phillips

How dare you question the operational use of pinup girls.

Pipe down, sonny. He's free to post any viewpoint he likes.




No matter how stupid.:rotfl:

[Captretman]

dmlavan

I'm not familiar with file suffix .7z. What do I use to open this file?

Thanks, Captretman

[modisch]

Originally Posted by Captretman

dmlavan

I'm not familiar with file suffix .7z. What do I use to open this file?

Thanks, Captretman

7-zip. website here.

-m

[Pisces]

Originally Posted by swdw

You mean like this?
http://www.igougo.com/travelcontent/...PhotoID=328270

I would say that both views are physically impossible for the moon. Simply because the moon cannot reflect sunlight from it's shadowside. As the moon is way much closer than the sun, and when both are together in the sky, the light of the sun only strikes the far side of the moon (for us behind it). And thus cannot reflect off of the side of the moon that is pointing to the earth. Nuc's screenshot must be a bug or graphic-file anomoly.

While SWDW's image looks more like a split-path refraction of the sun's rays through parts of the earths atmosphere (bending due to temperature variations), creating a double picture of the sun. Aka an optical illusion or 'fata morgana', just like the watery surface appearing on highways/roads in the distance on a hot day. As the lower 'orb' is straight below the fuzzy glowy blob above it, and has no texture, I bet it is not the moon but the sun itself.

[Rockin Robbins]

Originally Posted by swdw

You mean like this?
http://www.igougo.com/travelcontent/...PhotoID=328270

Both the SH4 picture and the picture you posted are not possible.

The phase of the moon is a direct result of its angular distance from the Sun. The corollary to that is that each phase of the moon rises and sets at the same solar time, for instance, the half moon rises at exactly 9:00 pm and sets at 9:00 am solar time.

Therefore, in the SH4 screenshot, the moon is approximately a half moon. As such, it would rise 90º after the sun set, 3 hours at 15º per hour, exactly 21:00 as I said above. Instead of 90º SH4 renders it less than half a degree from the solar position, which would result in a new moon. We would be looking at the unlit half of the moon. You could not see it for the sun's glare.

Swdw, your shot is an obvious fake. The first giveaway is that the moon ½º from the sun would be at 1/720 phase, essentially a new moon as outlined in the above referring to the SH4 screenie. The other blatant error is that they chose to paste the moon in at half the size of the sun. In reality they are both about half a degree in diameter, so close to the same size that you'd need a micrometer on the image to tell the difference. At perigee the moon is slightly larger than the sun. At apogee it's slightly smaller. The sun also varies slightly in size depending on whether the Earth is at aphelion or perihelion. In either case the change in size is not discernable to the naked eye and they are essentially identical in angular size.

A nice concise confirmation of all I say can be found here and a thousand other places.

OH! What about the setup in your Almanac above? The moon set 26 minutes after the sun. The earth rotates a degree every four minutes, so the moon would be 26/4 or 6½º above the sun or 13 solar diameters above. That's a very different spot from where SH4 renders it. Stand by for a plot, which I'll paste here.



You can see the moon labeled. It's a new moon, only 4/1000 illuminated, as I said 13½ solar diameters above the moon. This plot is two minutes before sunset, December 18, 1941. The green line on the bottom is the horizon. Astronomical charting courtesy of Cartes du Ciel, a masterpiece by Patrick Chevalley.

Time to go cut the grass!

[Nuc]

Originally Posted by Rockin Robbins

Time to go cut the grass!

Thanks for the explaination RR. Boy I'd like to need to cut the grass (not actuall cut it, but just need to) We've barely gotten rid of the snow

[MrSargyano]

Not knowing sunrise and sunset in my particular region (at least roughly) was rather bothersome. This mod should nip that in the butt! Thank you!

@ Rockin Robin: Your intelect is most admirable.

Regards,
Mr Sargyano