Moon, Jupiter and Cloudy Skies!!

10 March - 7:30 pm CDT

10 March – 7:30 pm CDT

   So, as a follow-up to Sunday evening’s pictures of the Moon with nearby Jupiter to the west (right side), I went out last night planning to get some pictures of the waxing gibbous Moon on the east side of the Moon. As the banner graphic and the slideshow illustrates it was sort of a typical evening for me. It got cloudy, however the clouds thickened and thinned allowing me a few pictures of the Moon. As these two cropped pictures show it is a challenge to have an exposure setting that allows the dimmer Jupiter to show up without overexposing the much brighter Moon.
   For both pictures I used the same shutter speed of 1/13 second, and the same ISO of 200. However the Moon showed up best with a small aperture setting of f32, while Jupiter was set to f5.
   While waiting for a break in the clouds I started taking a picture sequence of the sunset. For some of the later pictures I adjusted the aperture setting to smaller values which in turn brightened the picture.

               Hover the cursor over the slideshow to see the controls.

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Caution: Objects viewed with an optical aid are further than they appear.
   Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.

Imbolog 2014

shadowsGroundhog Day
   It has become a tradition in the United States to watch for a ground hog to emerge on the 2nd of February. We know this as Groundhog Day, an event that originates from ancient Celtic tradition. Groundhog Day was known as Imbolog, or sheep’s milk, a time for nurturing young sheep and planting spring crops. The belief arose that if Imbolog were to be sunny and clear, then winter’s effects would endure, foreshadowing a long winter. However, if skies were overcast, then the warmer days of spring would arrive early. To farmers then and today, an early spring means early spring planting and a subsequent early harvest. Often fires were lit to commemorate the event as fires were a sign of warmth and light, both of which increased as days lengthened.

   German immigrant farmers are credited with bringing Groundhog Day with them to the United States as they settled in Pennsylvania. To them, February 2 was called Candlemas Day, because of the practice of lighting candles on this day in celebration of early planting. The Germans believed that the badger was able to predict the weather on the basis of whether or not its shadow appeared. If the badger, or ground hog, saw its shadow on Candlemas it would be scared and return to its burrow for another six weeks-to sleep through the long winter. However if the skies were overcast then no shadow would appear, and an early warm spring would be expected.

   So year after year, since 1898, crowds have gathered in Punxsutawney, Pennsylvania on February 2 to wait for a certain ground hog to emerge from its burrow. Today the belief in this as a predictor of weather is not nearly as consequential as it appears despite all the hoopla created by the news media. Yet there is some scientific rationale to the ritual, albeit not in the accuracy of the forecast. When the skies are clear temperatures tend to be cold as the ground radiates heat absorbed during the day back into the atmosphere. When skies are overcast, temperatures tend to moderate as clouds trap heat nearer the ground.

   
   
   
Caution: Objects viewed with an optical aid are further than they appear.
   Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.

Harvest or Hunter’s Moon?

Clip Art by George Reed. Used with permission.

Clip Art by George Reed. Used with permission.

   Each full Moon has a name, or actually several names depending on the culture or part of the world. In the United States the full Moons of September and October are both named for practical reasons in that one is called the Harvest Moon while the following one is called the Hunter’s Moon. Unfortunately the definition of the Harvest Moon apparently may be either the full Moon closest before the September Equinox, or the closest full Moon after the September Equinox.
   It would be much simpler if this were determined by the full Moon closest to the September Equinox, making this year’s Harvest Moon in September and the following full Moon which is today, 18 October, the Hunter’s Moon.

kc_chiefs_moon   So what exactly is a Harvest or a Hunter’s Moon, and what makes them more significant (if they are) over other full Moons? The significance lies in the idea that September is typically harvest time at mid-latitudes in the United States and that once the fields are cleared the Hunter’s can more easily spot and ‘bag’ their prey. It is also significant in how the Moon rises each evening around the time of full Moon in September and October.

ecliptic-ani   The path or angle
the Moon rises is less steep than at other months so for a few days the Moon rises only about 30 minutes later rather than the 50 or so minutes of later rising time during other months. This in effect means more bright full moonlight later into the evening allowing farmers and hunters to take advantage of the extra light. The change in the angle that the Moon rises, and conversely sets, varies as the angle of the ecliptic changes as the Earth revolves around the Sun going through the cycle of seasons. As this animated graphic is showing this angle changes each month for the same reason that we have seasons – the axial tilt of the Earth.

Like 2 salt grains in the ocean here are two useful resources about the Moon out of the ‘Sagans’ of lunar resources that are out there. (1 Sagan = “billions and billions”
   Download the Lunar CRater Observation and Sensing Satellite (LCROSS Storybook)
   Download the Lowell Observatory Moon Clock. (PDF 79 Kb)

   ‘Rock it’ to the Moon in an animated simulation of a crewed Constellation Program mission to the Moon. This is actually a combination of two separate videos that I cut apart and spliced back together to reduce the length. (5m49s)

   Just enjoy it!! (1m49s)

   And of course Neil Young singing “Harvest Moon”

   
   
   Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.

Preview September Qué tal

voki   As the subject line states, the September preview issue of Qué tal in the Current Skies is now online and available at this temporary web address: http://currentsky.com/2013/sep13/index.html
   It will be at its regular web address in a few days.

   Thank you for your support and encouragement.
   Clear Skies…
   Bob Riddle

   Click here to go to the Qué tal in the Current Skies web site for more observing information.

It’s the Time of the Season

A Martian Year

A Martian Year – at One Earth Month Intervals

   Today is the northern hemisphere spring equinox on the planet Mars as the planet transitions from winter to spring during its 684 Earth day orbit around the Sun. Seasons on Mars are marked by the planet’s heliocentric longitude coordinates using the position of Mars along its orbit around the Sun. Each seasonal start/ending point is 90 degrees apart, but because of its elliptical-shaped orbit each Martian season is of varying lengths. At the Martian spring equinox Mars is at 0 degrees longitude.
   I’m not exactly sure why this particular date is used but by international agreement astronomers have selected 11 April, 1955 as 0 degrees for year 1 of this Martian calendar. What this means is that today, 31 July Earth time, is the start of a ‘new year’, the first day of spring for year 32 using the aforementioned calendar system.

Year 32
0 degrees — Spring Equinox — Jul 31 2013
90 degrees — Summer solstice — Feb 15 2014
180 degrees — Fall Equinox — Aug 17 2014
270 degrees — Winter Solstice — Jan 11 2015
Year 33
0 degrees — Spring Equinox — Jun 18 2015

Learn a little (or a lot) more about Mars at the NASA/JPL Mars Curiosity mission web site.

Here is approximately 3 minutes worth of Mars from the Orbit performance.

   
   
   Click here to go to the Qué tal in the Current Skies web site for more observing information.

3 Amigos – The Line Up

'3 amigos'

‘3 amigos’

   This evening, Saturday 1 June, look westward shortly after sunset to see three planets arranged in a diagonal line – from ‘top to bottom’ – Mercury, Venus, and Jupiter as this graphic shows.

Click on image to see it full size

Click on image to see it full size

   As the sky darkens and the planets are setting grab your binoculars or telescope and take a closer look at Mercury. This innermost planet is very close to the open star cluster M-35, also described as NGC-2168, located near the feet of the Gemini Twins. Just below M-35 is a fainter and more compact open star cluster NGC-2158. Click on this image to see it full size and as an animated zoom in showing more detail.

   Celestial objects with the letter ‘M’ preceding the number refers to objects observed and catalog by the French astronomer Charles Messier. Objects having the letters ‘NGC’ preceding the number refer to objects that are listed in the New General Catalog of celestial objects.

   Click here to go to the Qué tal in the Current Skies web site for more observing information.

Life in Tornado Alley

   Living in western Missouri near the stateline with Kansas places us in the area of the midwest known as “Tornado Alley”. While we have been very fortunate to not have had any tornadoes close by we have had to deal with the severe weather that accompanies tornadoes – including winds over 50 mph, and like this morning some really heavy torrential rains with thunder and lightning. In the span of less than 30 minutes the creek (aka the ‘river’ as our granddaughters call it) rose over its banks and flooded into the backyard. The base of the creek is at least 3 feet below the bottom of the fence and as the pictures show the water rose more than halfway up the fence and into the yard.

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A 1-minute look at the storm and flooding this morning.

   Click here to go to the Qué tal in the Current Skies web site for more observing information.