The
purpose of this feature is to give scout leaders, educators and naturalists an
idea of some of the natural events coming up each month. We will try to
cover a variety of natural events ranging from sky events to calling periods of
amphibians, bird and mammal watching tips, prominent wildflowers and
anything else that comes to mind. We will also note prominent
constellations appearing over the eastern horizon at mid-evening each month for
our area for those who would like to learn the constellations. If you have
suggestions for other types of natural information you would like to see added
to this calendar, let us know!
Though we link book references to nationwide sources, we encourage you to
support your local book store whenever possible.
Notes From August 2021
What a crazy August! It was a month of storms and I had only one night
available for taking a sky shot. On August 8th I had about
three hours of clear sky, and a persistent high-altitude haze gave the
brighter stars colored halos. Still, it was fun to get out under the
stars and I was spared the violent weather that some had. I
decided to image the North American Nebula in Cygnus. The bright star at
upper right in the image is Deneb, in the tail of the swan.
North American Nebula, August 8th, ZWO ASI2600 camera and Nikon
200mm Lens at F5.6. Total exposure time 2 hours and 4 minutes.
This image was taken with a 200mm lens attached to my astro camera and
mounted on a small portable mounting. The nebula was first noticed by
William Herschel on October 24, 1786 from Slough, England. Its
popular nickname was given it by the German astronomer Max Wolf, who
noticed its continental shape in photographs he took in 1890. Just to its right in the image is the
Pelican Nebula, appropriately positioned off the "east coast". Distance
estimates vary, but the most recent data place it around 2,590 light-years
away.
The reddish colors in the nebula come from hydrogen gas that is
fluorescing due to radiation from a bright star within the nebula. Recent
evidence suggests that the star that illuminates the nebula is just off
the coast of "Florida" , but hidden in optical wavelengths by the dense
clouds of dust there. Like most nebulae that shine in the light of
hydrogen alpha, the North American Nebula is a region of new star
formation.
On clear nights you can see a faint glow from the area of the
nebula and sometimes pick out parts of the continent-shaped form in
binoculars. The nebula is unfortunately too faint for the red glowing
hydrogen to be visible in binoculars. Both Deneb and the bright orange
star off the "west coast" are fairly bright naked eye stars. The
distance between the two stars is about 4-1/2 degrees, so the field will
fit comfortably in most binoculars.
On August 17th I came across this Eastern Mud Turtle, Kinosternon
subrubrum, crossing a trail on the farm where I live.
Eastern Mud Turtle, August 17th, iPhone
Eastern Mud Turtle Plastron
I've only come across a couple of these turtles since I've been
here and see many more Eastern Box Turtles. The carapace does not flair
out at the bottom like a box turtle and it's obvious even at a distance
that you have a different species. Below on the left is an image of an
Eastern Box Turtle I photographed the following day.
The only species with which you might confuse them are the musk turtles,
which can look very similar. You can tell them from musk turtles by
looking at the plastron beneath. It is hinged in two places while musk
turtles have plastrons that have only one hinge. They also have
more fleshy material in the hinge areas. Like Eastern Box Turtles, male Eastern
Mud Turtles have a concave plastron, while the females plastrons are flat.
The posterior hinge on the plastron in the image at right is harder to see than
the anterior hinge.
Eastern Box Turtle, August 18th
Habitats include shallow slow-moving bodies of water with emergent aquatic
vegetation. They will often burrow beneath the soil if their pond
or wetland dries up. The day before I found this Eastern Mud Turtle we had accumulated about two inches of rain. In such wet conditions they
often travel overland, and our paths happened to cross. They continue to
wander until conditions begin to get drier, at which time they burrow
again. Their diet consist mainly of small invertebrates. Winter months are spent in hibernation in chambers beneath the frost
zone. They can live to be more than fifteen years old.
M
ost of the information used here was taken from
Niemiller, M.L., & Reynolds, R.G., & Miller, B.T. (2013) The Reptiles of
Tennessee. The University of Tennessee Press/Knoxville.
I first became aware of forktails when we were conducting an all taxa
bio inventory for the
Owl's Hill Nature Sanctuary in
Nashville. I spent several days wading around their
ponds after documenting most of the dragonflies from the shore. Forktails
are a subgroup of damselflies, which in turn are closely related to
dragonflies. Forktails are
much smaller than dragonflies and easily overlooked. I found them flying within a foot of the
water's surface among dense aquatic vegetation.
Fragile Forktail Male, August 30th, Nikon 105mm Micro Lens and
Nikon D5600 camera. Three-image focus stack.
I was stunned by the images I made of
the forktails at Owl's Hill. They are
like hummingbirds are to the bird world or like jumping spiders are to
the arachnids. They are small and jewel-like. They don't zip around like
dragonflies. Their wings are a blur when they take flight, but they seem to just
float slowly
from one aquatic plant to another. They are also much smaller than
dragonflies. The one pictured above is no more than
three-quarters of an inch long.
Fragile Forktail Shoulder Stripes, August 30th
On August 29th I spotted a female Fragile Forktail early in the day, and
when I came back later in the day, it had not strayed more than a foot
from where I originally found it.
The following day I returned to the same spot and spotted another Fragile
Forktail, this one a male, again in the same area. The previous
evening I looked up the field marks for this species. When I looked
down from above I saw two broken shoulder stripes, looking like double
exclamation marks!! This separates them from the similar Eastern Forktail,
which look similar but have unbroken shoulder stripes.
Two mating Eastern Forktails are shown in the image below taken at
the Owl's
Hill Nature Sanctuary in 2015. This is the classic "wheel" or "heart"
position where the female (on the left) curls her abdomen to bring her
eggs in contact with the abdominal segment on the male where fertilization
takes place. Mating can also take place in flight. The male grasps the
female behind her head with a set of "claspers" on the tip of his final
abdominal segment.
Eastern Forktails Mating, Owl's Hill Nature Sanctuary, Nikon
105mm Micro Lens and Nikon D5600 camera.
The best way I've found to find forktails is to just move very slowly
through or close to dense and wet vegetation at pond edges. Remember
that you are mostly looking down to within a foot or so of the water's
surface.
On the same day that I photographed the Fragile Forktail, I spotted a
dragonfly flying to a branch of a pine that borders the pond. It was a
Banded Pennant, and the foliage surrounding it made a it hard to compose a
usable shot. Its face was visible, so I decided to try for a portrait.
Banded Pennant Portrait, August 30th, Nikon 105mm Micro Lens
and Nikon D5300 camera. Five-image focus stack.
The amount of detail in the eyes was amazing! You can clearly see each
hexagonal ommatidium
that together compose the compound eye. Each ommatidium acts like the
picture element (pixel) in a camera sensor in sending information to the
dragonfly's brain. There are up to 30,000 of these ommatidia in a
dragonfly's eye. Its vision is nearly 360 degrees, having a blind spot
only directly behind it. Whereas human vision is tri-chromatic, creating
color from cone cells sensitive to three wavelengths, dragonfly cone cells
sample a much larger part of the spectrum. Dragonfly eyes are one of the
most complex eyes in the animal kingdom.
Sky Events for
September 2021:
The September Equinox occurs at 3:21pm on September 22nd,
marking the
first day of fall to the Northern Hemisphere.
Evening Sky:
Jupiter, October 19th, 2020. 12.5 inch Newtonian Reflector and
ZWO camera.
Venus
is the brightest star-like object in the western sky after sunset, and
sets about an hour and 40 minutes after sunset at the beginning of
the month. Look for a pretty pairing of Venus and a young crescent Moon on
September 9th.
Mercury
is quite low in the west after sunset even at its highest altitude
this month. If you have a flat western horizon you might try for
it with binoculars about 30 minutes after sunset on September 5th.
Look to the right of Venus just above the horizon.
Jupiter
rises about 20 minutes after sunset in Capricornus at the
beginning of the month. On these hazy summer
nights it
may appear reddish as it rises. Jupiter's dusky belts change from night to night.
Since the planet takes less than ten hours to rotate, you can
watch details move across the disk during an evening. It's always fun to watch the dance of the four Galilean
moons!
Saturn
rises about an hour and a half before sunset at the beginning of the
month in Capricornus.
Look for it in the southeast at dusk above and to the right of
brighter Jupiter. By the middle of the month it will be due south
around 10:30pm EDT. This is a great opportunity to see Saturn.
Even in good binoculars the tiny oval shape of the planet and
rings can be seen.
If you've never seen Saturn, it's simply spectacular in just about any
size telescope.
In fact, even a good quality 60mm refractor will give a
better view of the ringed planet than Galileo was ever able to see. Saturn
was a puzzle to him. In his low-resolution telescope the planet appeared as three separate
discs - one large disc with a smaller disc on each side of it. A few
years later, he returned to look at the planet when the rings presented
edge-on. His two attendant discs had disappeared! He never solved the
riddle. He would have loved to
see the view available to just about any amateur astronomer today.
Constellations:
The Andromeda Galaxy.
Nikon 300mm f2.8 Lens at f4.0.
The views below show the sky looking east at 10:45pm EDT on September 15th.
The first view shows the sky with the constellations outlined and names
depicted. Star and planet names are in green. Constellation names are in
blue. The second view shows the same scene without labels.
In Andromeda, see if you can pick out the soft glow of the Andromeda
Galaxy. It's shown on the chart below. If you succeed in spotting it,
you'll be seeing an object that's about 2.5 million light-years distant!
Small telescopes may allow you to pick out the two brightest satellite
galaxies of the Andromeda Galaxy . These are NGC 205 (visible below
the core of the Andromeda Galaxy in the image at right) and NGC 221
(visible above and to the left of the core). Your best chance to see them
will be when the galaxy is high overhead.
September 15th, 10:45pm EDT, Looking East
September 15th, 10:45pm EDT, Looking East
On Learning the
Constellations:
We advise learning a few constellations each month, and
then following them through the seasons. Once you associate a particular
constellation coming over the eastern horizon at a certain time of year, you may
start thinking about it like an old friend, looking forward to its arrival each
season. The stars in the evening scene above, for instance, will always be
in the same place relative to the horizon at the same time and date each
September.
Of course, the planets do move slowly through the constellations, but with
practice you will learn to identify them from their appearance. In
particular, learn the brightest stars for they will guide you to the fainter
stars. Once you can locate the more prominent constellations, you can
"branch out" to other constellations around them. It may take you a little
while to get a sense of scale, to translate what you see on the computer screen
or what you see on the page of a book to what you see in the sky. Look for
patterns, like the stars that make up the "Square of Pegasus."
The
earth's rotation causes the constellations to appear to move across the sky just
as the sun and the moon appear to do. If you go outside earlier than the
time shown on the charts, the constellations will be lower to the eastern
horizon. If you observe later, they will have climbed higher.
As each season progresses, the earth's motion around the sun
causes the constellations to appear a little farther towards the west each night
for any given time of night.
A good book to learn the constellations is
Patterns in the Sky, by Hewitt-White.
For sky watching tips, an inexpensive good guide is
Secrets of Stargazing, by Becky Ramotowski.
A good general reference book on astronomy is the Peterson
Field Guide,
A Field Guide to the Stars and Planets, by Pasachoff. The book retails for around $14.00.
The Virtual
Moon Atlas is a terrific way to learn the
surface features of the Moon. And it's free software. You can
download the Virtual Moon Atlas here.
Apps:
The Sky Safari 6 basic version is free and a great aid for
the beginning stargazer. We really love the
Sky Safari 6 Pro. Both are available for iOS and
Android operating systems. There are three versions. The Pro is
simply the best astronomy app we've ever seen.
The description of the Pro version reads, "includes over 100 million stars, 3 million galaxies
down to 18th magnitude, and 750,000 solar system objects; including every comet
and asteroid ever discovered."
A
nother
great app is the Photographer's
Ephemeris. Great for finding sunrise, moonrise, sunset and
moonset times and the precise place on the horizon that the event will
occur. Invaluable not only for planning photographs, but also nice
to plan an outing to watch the full moon rise. Available for both
androids and iOS operating systems.
Amphibians:
Marbled Salamander
Frog and toad choruses start waning in September but some frogs and toads
are still calling. Spring Peepers
are also know as "Autumn Pipers" and can be heard calling from patches of
woods during the fall. Listen also for the very dry and scratchy
version of the Upland Chorus Frog's song on rainy fall evenings.
Green Frogs and Southern Leopard Frogs occasionally call.
You can locate many species that have been calling more frequently earlier
in the year by driving the back roads slowly on rainy nights.
You can sometimes find
the eggs of Marbled Salamanders in wooded wetlands in the fall.
Nature Notes Archives: Nature Notes
was a page we published in 2001 and 2002 containing our observations about
everything from the northern lights display of November 2001 to frog and
salamander egg masses.
Night scenes prepared with The
Sky Professional from Software Bisque
