Tony Martinez
Each month I will describe
sights of interest in the night skies of South Carolina. These sights will be
broken down into three sections; what you can see with the naked eye, with binoculars,
and with a small telescope. The best time to view the night sky is at and
around the times when the Moon is not visible, what is known as a New Moon; which
will occur this month on July 19th. For July, your best viewing nights will be
from July 7th to the 23rd. The Star chart below is set for Florence, SC on July
15th at 10 pm.
Venus Transit:
The ScienceSouth team and
over 130 visitors enjoyed perfect viewing for the June 5th Venus transit of the
Sun outside our pavilion at Freedom Florence. Everyone was able to view the transit
through our filtered 10-inch Dobsonian reflector, our H1 alpha solar scope, and
on a projection screen using our Sun Spotter. We were also pleased to have
Francis Marion University astronomy professor Dr. Jeanette Meyers join us. Dr.
Myers brought an additional filtered 10-inch Dobsonian reflector, and also
supplied everyone present with a pair of special solar viewing glasses. Visitors
were told to keep these glasses in a safe place to be reused on August 21, 2017
for the total solar eclipse that will pass over central South Carolina.
The Summer Milky Way:
Each summer I remind
everyone that this is a great time to be outside, hopefully at a dark sky site,
scanning the summer Milky Way. If
we revisit our place in the Milky Way galaxy we see that we are about 2/3 out
from the center. See image below:
As we revolve around the
Sun and look out into the southern sky, in the summer we are facing into the
center of the Milky Way, and in the winter, we are facing away from the center
of the Milky Way. This timing of course is just a chance/random happening. Therefore
in the summer, higher concentration of matter toward our galaxy’s center allows
us to view more visible stars, nebulas, and star clusters. Hopefully some of my readers have ready
access to local sites where the Milky Way is visible. The only downside for our
part of the country is that summer also brings humidity, which can interfere
with viewing the night sky.
If you are a serious
amateur astronomer and have never seen a brilliant Milky Way, you should try to
plan a vacation to a dark sky site. Many dark sky sites are in areas where
other interesting sights are nearby for daytime excursions. Sometimes a dark
sky site is so isolated that you have great nighttime viewing, and during the
day you sleep late, barbeque, and make new friends with your fellow amateur
astronomers. I used to drive 300 miles from New Jersey to an isolated dark sky
site in the Allegeny Mountains of northern Pennsylvania, called Cherry Springs
state park. The image below shows
the view of the Milky Way at Cherry Springs.
To find a dark sky site
you can search the Internet, or look in the advertisement sections of Astronomy magazine, or Sky and Telescope magazine. One of many
dark sky web pages is http://www.jshine.net/astronomy/dark_sky/.
Below are some images from that site.
The blue “tear drops” are
locations of private and public stargazing sites. Direct your attention to the
dark blue viewing areas. Notice that the closest blue area to Florence is the
Francis Marion National Forest, however, there are no sites there marked as
astronomy viewing areas. The
closest good “blue” viewing area is in Georgia, called the Deerlick Astronomy
Village, http://www.deerlickgroup.com/;
check it out.
Another consideration is
to look for dark sky sites near places where you have already planned a
vacation. Finally, for the very serious amateur, you might want to plan a trip
to Bolivia, South America next July for the Southern Skies Star Party; http://www.astronomicaltours.net/SouthernSkies/.
That is what you would call a true astronomy adventure! This Bolivia Star Party
is still on my wish list.
However, it is time to
return to Florence. Find the best local viewing site and direct your binoculars
and telescopes toward the southern sky. The image below is centered on the
constellation Sagittarius better known as the “Teapot” asterism. There are
eleven Messier objects shown in this image, along with some NGC (New General
Catalog) objects. Also note the location of the center of our Milky Way.
First scan this region
with a pair of binoculars. Depending on the darkness of your viewing site, you
should be able to spot several of the Messier (M) objects. Often you may only
note that your target is too fuzzy to be a star. Certain objects in this image
look well through a refracting telescope, such as M6 and M7. Most of the objects
are best viewed through a reflector, such as a Dobsonian, or through “Big”
binoculars. The most difficult Messier objects in this image are M20 and M21. Note,
the Lagoon Nebula M8 is visible to the naked eye at Cherry Springs Park.
This other image is
centered on the constellation Scorpius, and adds an additional four Messier
objects.
Have you ever looked up at
daytime clouds and saw shapes of animals or people? The “cloudy” Milky Way is
really millions of stars seen at a distance. Actual clouds in the Milky Way are
not white, but black and are made of dark matter blocking off the background
stars. Now use your imagination and look for the “dark horse” cloud in the
above three images of the Milky Way. If you have trouble locating it, see the
image below.
Naked Eye Sights: The summer Milky Way
Binocular Sights (7 to
10 power): As always, continue looking
for more Messier Objects to add to your list. In particular look toward the
Milky Way’s center in the southern sky.
Telescope Sights
(60-100mm): Use a reflector to
scan the Sagittarius/Scorpius region.
