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 July 2021
Summer is a great time to see globular clusters. These spherical clusters
of stars are distributed as a halo around our galaxy. Most are tens of
thousands of light-years away. On June 23rd I was testing out a new camera
system. It had been a hot humid day, but the evening air was thick and
cool. An orange sherbet full moon rose in the twilight. Venus, low in the western sky, had a distinctly red cast to it.
I needed a bright object to punch through the hazy sky. Messier 13, a
bright globular in Hercules, was overhead and seemed just right.
Globular Cluster Messier 13 July 23rd. 12.5 inch Newtonian
Telescope and ZWO ASI2600MM camera. Total exposure time 1 hour.
Messier 13 is one of the brightest globular clusters. Even small
telescopes in the four-inch range will show some of its stars at high
power. It helps to use averted vision. In large telescopes the views look
like a lower contrast version of the image above. Robert Burnham described
the first time that he saw Messier 5, a globular cluster in Serpens,
through the 40-inch reflector at the U.S. Naval Observatory station at
Flagstaff, Arizona:
"In that first stunning view it seemed as
if the fireflies of a thousand summer nights had been gathered
here, frozen forever in time and suspended among the stars."
The cluster is obvious in binoculars, and discoverer Edmund Halley (of
Halley's Comet fame) said of it, "It shows
itself to the naked eye when the sky is serene and the Moon absent."
Messier 13 is about 22,000 light-years distant and about 150 light-years
in diameter.
I finally had a relatively clear night sky on July 27th and I took the
opportunity to test a new wide-field configuration of my camera. The
astro-camera is connected via an adapter to a Nikon 105mm lens I normally
use for macro photography. This ensemble is mounted on the observatory
telescope, which takes care of the guiding. For the image below I selected
a region of Sagittarius above the spout of the "teapot", a group of stars
that truly looks like its nickname. On dark clear summer nights, the great
star clouds of the Milky Way seem to rise like steam from the spout of the
teapot. The brightest object, The Lagoon
Nebula, can be seen with the naked eye as a small fuzzy patch of light.
The Lagoon and Trifid Nebulas and Globular Cluster Messier 28
against
the vast star clouds of the Milky Way. ZWO ASI2600MM camera and
105mm lens. Total exposure time 56 minutes.
Above and to the right of the Lagoon Nebula is the Trifid Nebula. Both of
these nebula are glowing in the light of Hydrogen alpha, and both are
stellar nurseries. Part of the Trifid Nebula glows blue with the reflected
light of the bright stars within it. Both nebulae
are seen against the vast star clouds of the Milky Way. The globular
cluster Messier 28 is in the upper left quadrant of the image to the right
of a bright star that is the top of the "teapot". Another globular, NGC
6553, is to the left of the Lagoon Nebula, slightly below it and little
more than a third of the way from the Lagoon Nebula to the left border of
the image. It appears like a smaller, dimmer twin of Messier 28.
Sky Events for
August 2021:
The Perseid Meteor Shower
peaks on the night of August 11th-12th. Conditions are good for this
year's shower, with the young crescent Moon setting soon after the end of
astronomical twilight.
Evening Sky:
Saturn,
Tethys and Dione, June 11th, 2016, 20 Inch Newtonian Reflector and
ZWO Camera
Venus
is the brightest star-like object in the western sky after sunset, and
sets about and hour and 40 minutes after sunset.
Jupiter
rises about 50 minutes after sunset in Aquarius. This month it
will slowly make its way into Capricornus. On these hazy summer
nights it
will be appear quite 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 around sunset. The ringed planet is in Capricornus this
month.
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:
Messier 15
The views below show the sky looking east at 10:30pm
EDT on
August 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. New constellations this month are Pegasus, the Flying
Horse,
Andromeda, Princess Andromeda,
Triangulum, the Triangle,
Pisces, the Fishes, and
Aquarius, the Water Bearer.
In Pegasus, the reddish star
Enif marks the nose of the flying horse. Just above Enif is the
globular cluster Messier 15, another nice summer globular cluster to sweep
up in binoculars. It is about 33,600 light-years
away. The cluster was discovered by Jean Dominique Maraldi on
September 7th, 1746. Maraldi was searching for De Chéseaux' Comet at
the time.
August 15th, 10:30pm EDT, Looking East
August 15th, 10:30pm EDT, Looking East
On Learning the
Constellations:
Try to learn 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 August.
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 mobile device 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. If you want to see where the constellations
in the above figures will be on September 15th at 10:00pm EDT, you can stay up
till midnight on August 15th and get a preview. The westward
motion of the constellations is equivalent to two hours per month.
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.
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
