Puzzle Description:

Since nights last 14 earth days you'll need a good alarm clock so you don't miss your shift at work.

#1: bugaboo (bugaboo) on Nov 11, 2011

after initial dots from line logic start with edge logic on both the 4 clues in r1 (you will only get 1 more dot for each 4 clue but this is crucial)
then once you get a dot in r1c3 and r1c19 you can do edge logic on the 7 clues in c3 and c19 (if you try edge logic on the 7 clues too soon you wont get anywhere)
line logic to finish almost all the rest with smile logic twice to finish the last bit at the top
great solve
no guessing

Rather brilliant Brian, I absolutely love how this puzzle solved, so much fun in a 20x20, thank you! :)

Interesting concept - great puzzle

Excellent puzzle Brian,we still have an alarm clock like this.:)

Found to be logically solvable by gator.

Excellent puzzle. Ditto on the logic.

I needed a windup alarm clock like this, when I spent my summers working at a camp. Power outages were common, and I HAD to be up on time, to wake up all the campers!

Nice clean image, and REALLY fun solve!

Question: When traveling to the moon, what time zone do the astronauts use? Anyone know for sure?

Thanks for a timely entry! Or one could forget the alarm clock and since the moon has a light and dark side that never changes, one could consider that night is forever on one side and never on the other.

My guess is Central time, because they communicate(d) with Houston.

Fun solve!

It's likely they used Zulu (Greenwich) Universal time, as is used for military communication.

Joel is right. Info on Universal Time from NASA:
http://eclipse.gsfc.nasa.gov/SEhelp/TimeZone.html

I worked it a little bit differently from bug - I started with edge logic on the 7 columns on either side and then used line logic from there until the smile logic to finish.

Interesting take on the theme.

Anywhere on the moon you live in 14 days of light followed by 14 days of dark (except perhaps deep craters near the lunar poles). The Earth is always in about the same location in the sky since the moon is tidal locked to us. The "Full Earth" would appear about 4 times the diameter that the full moon does from here. The Full Earth would occur on the day of the new moon as seen from earth.

To further explain the tidal lock: Mercury is tidally locked with the sun, so one Mercury "day" (rotation) = one Mercury "year" (revolution). Thus the same face of Mercury always faces the sun.

The moon is tidally locked with the earth, so the same side always faces the earth. However, it orbits the earth every 28 days or so. Since the same side faces the earth during that whole time, it takes 28 days for the moon to make one rotation (or one "day").

Brian: Is the moon's axis tilted? If so, then the days & nights would vary over the year (away from it's equator) like earth's do. I would guess not (or at least not by much) or we'd see a little bit more than half (over the course of the year) as the tilt showed us more of the polar regions at solstices.
(Unless astronomy educators just want to Keep It Simple and not worry us with basically unneeded info.)

So you could live at one of the poles in constant twilight? :)

Or, I guess the moon is small enough that you could rotate between 3 or 4 moon bases, so you could have a steadier day/night schedule.

The moon's orbital axis is tilted a few degrees (my recollection is about 5) off of the ecliptic. The ecliptic is the imaginary line that the sun travels across the sky relative to the background stars. This AND the fact that the moon is in an elliptical orbit around the Earth so is speeding up and slowing down each month does allow us to see more than 50%. This apparent lunar wobble is called libration.

thx 4 entry..and education all

really nice!

Thanks.

A correction to Joe's response #16 above: Mercury does not always have the same side facing the sun. Mercury rotates exactly three times around it's axis for every two orbits it completes around the sun. From the point of view of a person on Mercury, a "day", the time from one sunrise to the next, lasts exactly two "years", the period of time it takes to orbit the sun (one Mercury year = 88 earth days).

Because days and nights are each 88 earth days long and there is no atmosphere to spread the heat around, nights get very very cold (-180 C or -280 F) and days get very, very hot (420 C or 800 F).

the settles it Bran, you'll have go by yourself

Goto next topic

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