Monday, February 09, 2015

Tales From the Dark Side (of the Moon)

Over the years, I have studied the moon.  How it was formed, it's orbit, and many more interesting tidbits.  Because of it rotation, we never see the dark side from earth.  Not many folks talk about the dark side ( except for the album).  I found a cool article in the Washington Post about new pictures from the dark side.  Here is a portion of the article:

Although it doesn't appear to spin from Earth's perspective, the moon does rotate, once about every 27 days. That's also approximately the same amount of time it takes the moon to orbit the Earth, once. The phenomenon is called synchronous rotation. In all, about 59 percent of the moon is visible from Earth over the course of an orbit. We never ever see 41 percent of the moon - the side that many call "dark."

But the "dark" side of the moon has always, from its perspective, gotten plenty of light. When Earth sees a waning crescent, the far side is nearing fullness. And it's light in another sense, too: the dark side has few of the distinctive dark spots that mark the Earth-facing side of the moon. Those spots are called maria, from the Latin word for sea, because early astronomers mistakenly thought they were lunar seas (they're actually volcanic plains). The smooth and dark maria cover 17 percent of the surface of the moon. Almost all of them are visible from Earth.

The mystery of the "dark" side's lighter surface has long been a difficult question for scientists. Although the going theory has been that the maria were the result of a huge asteroid impact, recent research suggests that the dark surface of the Earth-side moon is the result of ancient magma flooding.

Here is a great photo of the dark side.

Had some great storm sails over the weekend.  Thursday night it was blowing 20 and I took off for a solo night sail.  When storms are approaching, the wind shifts from a north west flow to a from the south flow.  Its nice because normally we have to tack several times to make it to the central bay.  With a south wind, we shoot out the harbor and start sailing towards Alcatraz on a port tack.  With just about 50% of the jib out, I took an hour long tack out towards the Gate.  Awesome sailing.

Sunday we had rain in the morning and then about noon it started to clear.  I headed up and was in the south wind about 2pm.  It was about 18-20 and I had a few nice reaches towards the City.  Only a handful of boats out and no ship traffic.  Then it really picked up and was 25+.  Made it in and thanked my lucky stars for this wonderful boat we have owned for 14+ years (average boat ownership is 2.5 years before selling).

Here is a look at the wind speeds at the Gate during my sail.  Gusts are on the right.

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