The Full Beaver Moon, Meteors and A Comet – November 16-17

beaver-poster

The Full Beaver Moon comes Sunday, brightening the sky and unfortunately making the Leonid meteor shower’s peak and Comet ISON more difficult to see.

The moon will be full at 10:16 a.m. EST Sunday, which actually means Saturday night’s moon will appear the closest to full.

The moon gets its name from the fact that November was the time of year fur trappers set their snares, before swamps froze, according to the Farmer’s Almanac. November’s full moon is also known as the Frosty Moon.

This month’s full moon unfortunately coincides with two other sky  watching opportunities,the Leonid meteor showers and the comet ISON.

The Leonid meteor showers, which appear to emanate from the constellation Leo, peak Sunday. Debris from Comet Tempel-Tuttle’s debris can produce up to 15 meteors per hour, best seen in the hours just before dawn, according to Astronomy magazine.

Leonid

The Leonids have produced in the past some of best shows of all of the meteor showers. In 1966, for instance, THOUSANDS of meteors per MINUTE were seen over a 15-minute period of time on the morning of November 17th.

According to the EarthSky article EarthSky’s meteor shower guide for 2013 people watching the shower said it felt like the meteors fell “like rain”.

And, “Some who witnessed the 1966 Leonid meteor storm said they felt as if they needed to grip the ground, so strong was the impression of Earth plowing along through space, fording the meteoroid stream.” (One wonders, considering it was the sixties, whether the observers were under the influence of hallucinogens!)

Comet ISON meanwhile could be visible in the early morning using binoculars by looking to the southeast horizon near the bright star Spica, part of the constellation Virgo, according to EarthSky.org.

The moon sets at 5:46 a.m. Sunday and 6:44 a.m. Monday, while the sun rises shortly before 7 a.m., so Sunday could be your best bet for early morning sky watching.

 

The Full Snow Moon

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This weekend, nights are lit by the waxing (increasing) gibbous (larger than half) moon, to be experienced as a sequence that culminates on Monday, February 25th, when the Full Snow Moon arrives at full phase at 3:26 p.m.

At that moment the side of the moon facing Earth will be fully lit because the moon will be opposite from the sun in its orbit around the Earth. Earth will be in the middle without blocking the sun’s light from reaching the moon: eclipses are infrequent because sun, earth and moon do not often precisely align.

The moment of full moon is different from its local rising time. Luna appears wholly round for about 24 hours, when it is rising and setting opposite the sun.

The Full Snow Moon rises on Monday, Feb. 25 at 5:51 p.m. in the east moments after sunset at 5:38 p.m. in the west-southwest. On the morning of Feb. 26, moonset in the west is at 6:33 a.m. opposite sunrise, which will be in the east-southeast at 6:34 a.m.

Nearly full moonlight shines during most of the 13 hours of darkness into the new week even though the waning (decreasing) gibbous moon rises close to an hour later each night.

February’s full Moon is traditionally called the Full Snow Moon because the heaviest snows fall in February.

Because hunting was difficult, some Native American tribes called this the Hunger Moon.

Other Native American tribes called this Moon the “Shoulder to Shoulder Around the Fire Moon” (Wishram Native Americans), the “No Snow in the Trails Moon” (Zuni Native Americans), and the “Bone Moon” (Cherokee Native Americans). The Bone Moon meant that there was so little food that people gnawed on bones and ate bone marrow soup.

Grand Illusion

Have you ever seen a beautiful full moon (like the one we had this past weekend) and tried to take a picture of it?  I have.  Here is the disappointing result.

Why does the moon seem so much smaller in the photograph than it did when I viewed it with my naked eye?

It’s an illusion.  One of the most famous of all illusions. Stated simply, the full moon, when just above the horizon, appears much larger than when it is overhead. Yet the moon, a quarter of a million miles away from the earth, always subtends the same angle wherever it is in the sky, roughly 0.5 degrees.

Even professional photographers fall for this one. Many photographs that you see in magazines, containing both a moon and a landscape, will be composites. The landscape will be taken with a normal lens, the moon taken with a telephoto lens, to get a bigger image.

How does this illusion come about? Since the moon always subtends an angle of 0.5 degrees, the image on the retina must always be the same. Clearly the problem is one of interpretation.

One simple experiment shows this to be so. A full moon just above the horizon will not appear so large to the human eye if a piece of paper is held up to that eye with a hole in it, so that only the moon can be seen through the hole and not the horizon. If the other eye is open at the same time, viewing both the moon and the horizon, the two eyes will each see different sized moons!

The reason is we ‘know’ that a cloud that is overhead will be larger than when it moves towards the horizon. And an airplane that is a mere speck on the horizon becomes large when it is overhead. And we are all familiar with standing under a tree which seems enormous, yet at a couple of hundred paces seems insignificant.

So much of our world is interpreted this way that we are ill-equipped to cope with an object like the moon, that subtends the same angle at the eye, whatever position it occupies in the sky. And so our brain ‘interprets’ the image that it ‘sees’, and tells us that the moon is larger than it really is.

And isn’t that wonderful??