Hi everyone,
On November 23, 1965 an eclipse of the sun began blotting out the sunlight over Southeast Asia. This was during the peak of the Vietnam War. As the ancient custom of the villagers in that area was to shoot flaming arrows towards the Sun to reignite the Sun’s fading embers, a dilemma was encountered. At a certain South Vietnamese Army base they didn’t any arrows available to shoot, but then it occurred to them that they did have some heavy artillery pieces, and so they began shooting them towards the Sun. They did indeed successfully reignite the Sun…but, also in the process managed to blow to smithereens a friendly village some miles down the road.
The moral of this true story is this: When our eclipse occurs on the 21st, don’t go and do likewise.
This month’s newsletter will look at the August 21st eclipse and how you can participate in it come rain or shine.
But, before we begin, I will mention the feedback I received regarding last month’s article discussing the possible format changes in the newsletter.
A faithful follower in Talladega says “please, please, please keep the almanac, for I love it dearly and read it avidly every month.”
Another devoted Markaholic indicates that he is “OK with the format change if that’s what’s wanted. It looks like the core of what I love about it is still there.”
An interesting idea for an article was received, as was our first article!
Thank you for your support for the newsletter. I appreciate that you appreciate it
Remember this is YOUR newsletter. There is an open invitation for articles, whether from Officers, members or from our readers near and far.
Officers, you have an open platform available for expressing your ideas, thoughts and concerns. Readers whether ALERT Members or not, your insights, interests and input concerning amateur radio, emergency communications, preparedness, meteorology and astronomy is welcome.
Articles (which I will proofread and edit) may be submitted to wd4nyl@bellsouth.net
Lastly, don’t forget our next ALERT meeting Tuesday August 8 at 7PM at the National Weather Service Forecast office at the Shelby County Airport.
I plan on being there, as Mark needs to pay his dues.
Do you need to also? Hint, hint…
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July ALERT MeetingBy Justin Glass N0ZO
The July 2017 meeting had 9 (N4PHP, NZ20, N0ZO, KM4KBH, KJ4OPX, KK4OHW, N4GHP, K4FSO, WD4IGK) people attending in person, and 7 (KD4QHZ, WX4RON, KK4UDU, KN4SXE, K4VS, WD4NYl, KQ4JC) via the teleconference.
There’s a new amateur radio club that has formed in Shelby County, the Central Alabama Amateur Radio Club (CAARC – club www.caarc) which meets on the first Wednesday of the month.
They offer testing with Laurel VEC, which is the only testing group that offers exams for free. N0ZO is the team leader in charge of testing. CAARC was the first testing site that Laurel had in Alabama. After testing, a typically short club meeting follows.
For more information on Laurel VEC, visit their website at https://www.laurelvec.com/
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Solar Eclipses and Amateur Radio
One sunny spring day near noon, the sky began growing progressively darker and the temperature dropping noticeably. The day lilies and dandelions began to close and the birds started retreating to their nests. On the ground the sunlight filtering through the leaves formed dozens of tiny crescents on the ground and overhead the sun was nothing more than a fingernail clipping of a crescent in the sky.
The day was May 10, 1994, and central Alabama was experiencing an Annular Solar Eclipse. Which is an eclipse where the sun is not completely covered by the moon, because the moon is too far away in its orbit, and therefore slightly too small to cover the entire solar disk.
During the annular solar eclipse of 1994, as an experiment NOAA & NASA requested ham radio operators operate on the MF & lower HF bands to see what effect the sudden loss of sunlight would have on the layers of the ionosphere.
Propagation in the Medium Wave Frequencies between 300 kHz and 3 MHz and the lower High Frequency or Short Wave Bands from 3 MHz to 10 MHz is much more limited during daylight hours as the D layer of the ionosphere absorbs signals heading for the middle and upper levels of the ionosphere and absorbs any signals that actually penetrate the D layer and are reflected back towards the Earth. This is why you never hear WWL 870 in New Orleans or WGN 720 in Chicago during daylight hours on the AM broadcast bands.
As the sun goes down, the D layer, no longer receiving the influx of solar radiation, fades away allowing signals to reach the F layer and gradually distant signals begin coming in. WSB 750 in Atlanta, WSM 650 in Nashville, along with WWL gradually fades into reception.
As the night progresses the F layer rises in altitude allowing you to hear more distant stations such as KDKA 1020 in Pittsburgh, WGN, WLW 700 in Cincinnati, WBAP 820 in Ft. Worth, KOA 850 in Denver, XERF 1570, Ciudad Acuña, Mexico, KSL 1160 in Salt Lake City, the desert Southwest and then the West Coast, and in the opposite direction, into the Caribbean, with PJB, Bonaire, Netherlands Antilles on 800 kHz.
This effect is gradual.
But, what happened when the sunlight was suddenly cut off piqued scientist’s curiosity.
Hams were encouraged to begin making contacts a half hour before the beginning of the eclipse and ending a half hour after the end.
The results were interesting.
One station in New Mexico near the center of the shadow reported he “experienced significant enhancement of medium wave reception half an hour before and after annularity (the midpoint of the eclipse). At its peak the reception resembled that experienced at the time of sunset. One interesting thing he observed was the shift in the location of the stations he heard. “As the eclipse progressed, stations to my southwest faded out and stations to the northeast faded in.”
Closer to home, in Birmingham, where the sun was blocked 72%, a friend Marvin, W4WU, now silent key, said “that’s the wildest propagation I’ve heard in 50 years of ham radio.”
Others further from the shadow reported no significant effect.
This brings us to August 21, 2017.
While I’m hoping we will get decent weather so we can view the eclipse, which will be covered further in the Almanac section, it is the middle of summer and Mother Nature might throw a cloud cover at us, as she did during the March 7, 1970 eclipse, when it was cloudier than used motor oil in Birmingham.
Should this happen, I would urge you, if you can, remembering it is a workday, starting at 11:30 AM & ending at 3:30 PM pick a spot on the radio dial between 525 kHz and 10 MHz and start listening or if in the ham bands, trying to make contacts. This range includes the AM broadcast band, Medium Wave Shortwave Bands, 160, 80, 60, 40, & 30 Meter Ham Bands and lower Short Wave bands. If you have no HF gear, you could use the AM radio on your stereo or car radio, which unless things have changed, experience has shown me are actually surprisingly good receivers, and see if anything strange happens.
A few days before the event you should “learn the band.”
Now realistically speaking you can’t “learn” the quirks and stations over a 10 MHz wide frequency range in just a couple of days. But, you can pick specific portions to “specialize” in. For instance most operators on HF have learned the characteristics of specific bands, not the entire radio spectrum. Though, knowing what’s happening “between the bands” is very useful knowledge to have.
“Learning the band” involves just tuning up and down the band; let’s say the AM Broadcast Band, during the target time frame for a couple of days and writing down every station you hear. Not just the strong ones, but, the weak ones also.
This works for any band during normal operations too, making you in a short time, an “expert” in your little corner of the dial, allowing you to know if the band is really open or not.
During the eclipse tune around and if a station appears where it wasn’t encountered before, you know something “different” is happening. If you are accustomed to “working HF” you probably already have a decent idea of what should or shouldn’t be happening, and will notice if something unusual is happening.
Log what you hear or who you contact. Compare it to other “normal times” as well.
And, if you don’t mind, let me know your experiences at wd4nyl@bellsouth.net
Along the same line, there will be an on the air event, the “Solar Eclipse QSO Party (SEQP)”. This is a HamSCI-ARRL sponsored operating event “to generate data to study ionospheric changes during the eclipse.”
This event will occur on August 21 from 14:00 – 22:00 UTC. Beginning with the first dimming of the partial eclipse at about 16:00 UTC in Oregon through the total eclipse and ending with the last shade of the partial eclipse at about 20:15 UTC in South Carolina.
This will occur on the 160, 80, 40, 20, 15, 10, and 6 meter bands, but, not 60, 30, 17 or 12 meters, as contesting is not allowed on those bands.
For more information go to http://hamsci.org/seqp-rules
As for Mark, I have to work, of course, but, I doubt I will get much work done, with me in the parking lot staring at the sky….or searching for a live feed on YouTube should it rain.
Just don’t tell on me.
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Mark’s Almanac
August was originally named “Sextilis”, the sixth Roman month. It was renamed August in honor of Caesar Augustus and lengthened to 31 days, to equal Julius Caesar’s month of July.
August is hot and humid and summer temperatures remain at or near their summer peak.
The rapid vegetation growth of spring is over, and, since conditions are now perfect for the growth of mold, fungi & germs, plants have a “used” look, which is enhanced if rainfall is scarce.
In August the choir of cicadas whine in the afternoon & towards the end of the month the big Yellow Sulphur Butterflies will begin heading to the South-Southeast, giving hints of their soon upcoming fall migration & cats will begin to hint of growing their winter coats.
Hurricane breeding grounds in August are the Atlantic, with Low Latitude storms forming off of Africa crossing the Ocean and either threatening the Eastern Seaboard or striking the Leeward Islands, entering the Caribbean and then striking the Yucatan, or the Western or Northern Gulf coast. Breeding grounds also include the Caribbean and Gulf of Mexico.
August is second only to September in the number of Tropical Storms and Hurricanes. From 1851 to 2016 there have been 383 Tropical Storms and 241 Hurricanes, the most notable storms being Hurricanes Camille and Katrina in 1969 and 2005, which devastated Mississippi and Louisiana and Hurricane Andrew which ravaged South Florida in 1992.
21% of a year’s Hurricanes occur in August, however, 85 to 95% of land falling Hurricanes have not occurred by August 15.
Looking skyward, at the beginning of the month, Mercury shining at magnitude 0, is low above the west-northwest horizon 30 or 40 minutes after sunset.
Venus shines brightly at magnitude –4.1 in the east before and during dawn. Look for the fainter orange star Aldebaran far to her upper right. To Venus’s lower right, another orange star Betelgeuse is rising, as the constellations of Winter begin peeking over the horizon.
Mars is hidden behind the Sun.
Jupiter shines brightly at magnitude –1.9, in Virgo, in the southwest in early evening. The fainter star Spica shining at magnitude +1.0, glitters 8° or 9° left of Jupiter.
Saturn, drifting in the legs of Ophiuchus, glows steadily at magnitude +0.2 in the south at nightfall. The fiery star Antares, less bright, twinkles 13° to Saturn’s lower right. Delta Scorpii, the third-brightest object in the area, catches the eye about half that far to the upper right of Antares.
Uranus shining at a borderline naked eye visibility of magnitude 5.8, in Pisces, is high in the southeast before dawn.
Neptune shines faintly at magnitude 7.9, in Aquarius high in the south, before dawn begins.
August’s Full Moon will occur August 7 at 18:11 UTC or 1:11 PM CDT. August’s Full Moon was called “Fruit Moon” in Cherokee Folklore, “Women’s Moon” among the Choctaw, “Sturgeon Moon” by the Algonquin because the large sturgeon fish of the Great Lakes and other major lakes were more easily caught at this time of year. This moon has also been known as the Green Corn Moon and the Grain Moon and at one time was called “Dog Days Moon” by the Colonial Americans.
Though not visible from North America, there will be a Partial Lunar Eclipse on August 7. A partial lunar eclipse occurs when the Moon passes through the Earth’s partial shadow, or penumbra, and only a portion of it passes through the darkest shadow, or umbra. During this type of eclipse a part of the Moon will darken as it moves through the Earth’s shadow. The eclipse will be visible throughout most of eastern Africa, central Asia, the Indian Ocean, and Australia.
The Perseid Meteor Shower peaks on the night of August 11 & 12, with 50 to 60 meteors per hour. This shower, produce by debris from Comet Swift-Tuttle, which was discovered in 1862, ranks as the best of the best, famous for producing bright meteors. The shower runs annually from July 17 to August 24. It peaks this year on the night of August 11 and the morning of August 12. The waning gibbous moon will block out many of the fainter meteors this year, but the Perseids are so bright and numerous that it should still be a good show. Best viewing will be from a dark location after midnight. Meteors will radiate from the constellation Perseus, but can appear anywhere in the sky.
On August 21 the Moon will be located on the same side of the Earth as the Sun and will not be visible in the night sky, which is known as New Moon. This phase occurs at 18:30 UTC or 1:30 PM CDT. This is the best time of the month to observe faint objects such as galaxies and star clusters because there is no moonlight to interfere.
As covered in our main article, on this date there will be a Total Solar Eclipse. This is a rare event for observers in the United States. The last total solar eclipse visible in the continental United States occurred in 1979 and the next one will take place in 2024.
The path of totality will begin in the Pacific Ocean and travel through the center of the United States. The total eclipse will be visible in parts of Oregon, Idaho, Wyoming, Nebraska, Missouri, Kentucky, Tennessee, North Carolina, and South Carolina before ending in the Atlantic Ocean.
A partial eclipse will be visible in most of North America and parts of northern South America.
NASA Map and Eclipse Information http://eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2017Aug21T.GIF
Detailed Zoomable Map of Eclipse Pathhttp://xjubier.free.fr/en/site_pages/solar_eclipses/TSE_2017_GoogleMapFull.html
Event times are as follows (note that Alabama will get only a partial eclipse, do not directly look at the Sun):
Beginning Mid eclipse Ending CoverageBirmingham 12:00:39pm 1:31:56pm 2:58:23pm 93%Huntsville 12:00:01pm 1:30:43pm 2:56:48pm 97%
If you head North from Birmingham on I-65 and travel through Nashville 225 miles north of Birmingham to Gallatan Tennessee, a 3 hour 30 minute trip, you can join a few thousand intimate friends and enjoy the full 2 minutes 40 seconds of a 100% total solar eclipse
The Gallatan eclipse timing (note only during the total eclipse portion can you safely look directly at the eclipse):
Partial Eclipse Begins 11:59:02 AMTotal Eclipse Begins 1:27:25 PM Midpoint 1:28:45 PM Total Eclipse Ends 1:30:05 PM Partial Eclipse Ends 2:54:14 PM How do you safely view a solar eclipse?
The way NOT to view an eclipse is by staring at the sun, or even worse looking at the sun with unfiltered binoculars or a telescope. To do so is to invite a lifetime of blindness.
It is NEVER safe to directly view the partial phases of any solar eclipse, or the maximum phases of an annular solar eclipse (an eclipse where the moon is smaller than the sun, leaving only a bright ring of sunlight) using the unprotected or naked eye. Even when 99% of the Sun’s surface is blocked during the partial phases of a solar eclipse, the remaining crescent is intensely bright and cannot be safely viewed without eye protection.
NOT recommended is viewing through smoked glass, old photo negatives, exposed x-ray film or stacked sunglasses, as they may very well block the visible light, but, will still allow infrared and ultraviolet light to pass unimpeded to cook what’s left of your retinas.
Some of the safe methods are as follows:
Pinhole Projection
The simplest and most inexpensive method for safely viewing a solar eclipse is called “pinhole projection”. A pinhole or small opening in a piece of cardboard is used to project an image of the eclipsed Sun onto a screen (white piece of cardboard) placed a couple feet behind the pinhole. The white cardboard is moved back and forth until a good focus and size is obtained. Making a pinhole projection box to safely watch a solar eclipse is a fun project for kids.
As mentioned in the preceding article, projected images of the eclipsed Sun can be seen on the ground as sunlight passes through leaves or even seen on the ground by loosely interlacing your fingers and allowing sunlight to pass through small openings between your fingers. Another amusing projection method is to use a kitchen straining spoon or a pasta colander. Anything with tiny holes can be used to project the partially eclipsed Sun’s image: a straw hat, a cheese grater, a lawn chair having a loose weave fabric, etc.
Binocular Projection
Any pair of binoculars can be used to project a pair of images of the eclipsed Sun onto a piece of white cardboard. After focusing the binoculars on a distant object, just point the binoculars up at the Sun, but not aiming them with your eyes, and project their images onto a piece of stiff white cardboard placed 1-2 feet behind them. The farther away the screen is from the binoculars, the larger the projected image of the Sun. This takes a bit of practice to get the pointing just right so try it out on a sunny day before the eclipse.
The same can be done with a tripod mounted telescope.
WARNING: Never look directly through the binoculars at either the Sun or the partially eclipsed Sun.
Welder’s Glass
Though they give the Sun an unnatural green color, a widely available filter for safe solar eclipse viewing, and endorsed by NASA, is a number 14 welder’s glass. These filters normally protect a welder’s eyes from the intensely bright glare of a welding arc. They come in a variety of shades with number 14 being the darkest – be sure to get a number 14 for eclipse viewing.
Welder’s glass filters are available through welding supply outlets and through retailers on the Internet.
Again, only number 14 welder’s glass filters are safe to use for looking directly at the Sun. Stacking two number 7 filters will not duplicate a number 14 filter, get a number 14.
Also, there is a welder’s filter that has a variable density. It changes darkness depending on the brightness of the welding arc (or light source) that it’s pointed towards. These variable density filters are NOT SAFE for looking at the Sun.
Eclipse Glasses
Though it may already be too late to obtain, in recent years inexpensive eclipse glasses have become increasingly popular for safely viewing of solar eclipses. They usually consist of specially manufactured filters mounted in a simple cardboard frame. Eclipse glasses allow you to look directly at the eclipsed Sun since the filters safely protect your eyes from any harmful rays.
However, this method I would approach with the greatest of caution, as many sources are selling counterfeit “eclipse glasses”. NASA has issue a warning about these fake glasses, and named a few companies that are trustworthy providers of lenses or glasses.
Here’s what you need to look for:
• The glasses should have certification information, with a designated ISO 12312-2 international standard.• The actual manufacturer’s name and address should be printed somewhere on the glasses.• Don’t use glasses that are wrinkled, scratched, or more than three years old.• Don’t use regular sunglasses, no matter how dark they are.
NASA recommends buying glasses from one of five manufacturers:
• American Paper Opticshttp://americanpaperoptics.com/our-products/eclipsers
• Baader Planetarium (AstroSolar Silver/Gold film only)https://telescopes.net/store/baader-astrosolar-solar-eclipse-glasses.html
• Rainbow Symphony which is featured in Astronomy Magazine http://links.mkt746.com/ctt?kn=6&ms=Mjk5MTUwMDAS1&r=NTAzNDM0NzY4OTc5S0&b=0&j=MTA4MzE0OTA0MAS2&mt=1&rt=0
• Thousand Oaks Opticalhttp://thousandoaksoptical.com/products/eclipse/
• TSE 17http://tse17.com/eclipse-shop/
Unfortunately, just looking for those five names on Amazon isn’t enough, since the counterfeiters are using names of the approved companies.
When you put them on you should see complete darkness unless you’re looking into the sun. You can also check the back for a safety seal.
The following are some tips to safely use eclipse glasses and filters.
Stand still and cover your eyes with your eclipse glasses or filter before looking up at the bright Sun. After glancing at the Sun, turn away and remove your filter — do not remove it while looking at the Sun.
If you travel to an area where you can view the total eclipse, within the path of totality, remove your solar filter only when the Moon completely covers the Sun’s bright face and it suddenly gets quite dark, to experience totality. But as soon as the bright Sun begins to reappear, replace your solar viewer to glance at the remaining partial phases.
I have resisted the temptation to say, as the news media gleefully assures, that “this is a once in a lifetime event”, especially since there have been 38 total solar eclipses in my lifetime, and the next one, though admittedly not in my backyard, will occur over central North America on April 8, 2024. The shadow will pass over Texas, Arkansas on onward to the Great Lakes and along the Canadian/New England border.
While I may not be anywhere near Texas or Arkansas in 2024, I DO plan on being somewhere “above the daisies” doing something hopefully fun.
Still, these are rare opportunities, so, even if it is a workday, try to catch a peek of this event!
3502 planets beyond our solar system have now been confirmed as of July 27, per NASA’sExoplanet Archive http://exoplanetarchive.ipac.caltech.edu/
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This month’s meeting will be on August 8 at 7PM at the National Weather Service Forecast office at the Shelby County Airport.
If for some reason you cannot attend the meeting in person, you can still participate via telephone. The teleconference number is 1-877-951-0997 & and the participant code is 741083.
Hope to see you there!
Mark / WD4NYLEditorALERT Newsletterwd4nyl@bellsouth.net
Mark’s Weatherlynx Weather Resource Databasewww.freewebs.com/weatherlynx/
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