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In this episode of Star Hopping with Kissimmee Park Observatory, we'll look at the Hercules
and Serpens region, and show you how to find these beautiful deep sky objects:
Messier 92 Messier 5
And the The Great Hercules Cluster, M13
Alright, Let's Go Star Hopping!
Hey Hello Hi and welcome to Episode 25 of Star Hopping with Kissimmee Park Observatory!
I'm Dave Hearn, and I'm absolutely on Cloud Nine to be your host.
Strange weather we’re having!
In this series of programs we'll show you the most beautiful sights in the night sky,
and explain exactly how to find them with your binoculars or telescope.
Well, I have gotten a bit ahead of myself with the sky, which is why I have done the
two astrophotography extras lately. But I wanted to get back to presenting some deep
sky objects, and tonight I have some great ones for you. These three targets this evening
are all globular clusters, but they are not rising until a bit later, around midnight
local time. So after you have had your fill of galaxies in the earlier hours, finish off
your observing session with the three beauties that I’ll show you in this episode.
So we have definitely transitioned from galaxies to globular clusters, although there are not
nearly as many gobulars available. But the ones that are immediately available are really
great. Let’s start off with one of the most famous ones, right after this.
The Great Globular Cluster in Hercules is also known as M13, and it was discovered by
Sir Edmund Halley in 1714, and catalogued by Charles Messier on June 1, 1764. If M13’s
discoverer’s name sounds familiar, your memory is correct: Sir Edmund Halley also
was the discoverer of Halley’s Comet.
M13 is one of the first deep sky objects found by beginning amateur astronomers. I remember
one cold year back in the 1970’s when I lived up in Pennsylvania, we were having a
winter that would just not give up, and I was observing in my front yard late one night.
I had plopped my 4 1/4” reflector down on top of the packed snow, and was checking out
the stars on a cold winter night. Edmund Scientific had some great telescope learning books back
in those days, and they had lots of cute little hand drawn illustrations in a book that came
with my little scope. I remember the little drawing of the man pointing the telescope
into the great Keystone of Hercules, to find a large globular cluster, mysteriously called
“M13”. I remember following the book’s instructions, and when I found the fuzzy glowing
ball of stars, I was so excited that I ran into the house and got my parents to make
them get bundled up to come out and look!! That was a very long time ago.
So let’s do our star hop to recreate those events of that cold night. Looking east around
midnight, you’ll see a fairly conspicuous trapezoid or “Keystone” of 4 stars, about
30 degrees up in the east. This is the main asterism in the center of the large constellation
of Hercules, actually the fifth largest constellation, named after the mythological hero and strong
man. The constellation is not particularly bright, composed of mostly 3rd and 4th magnitude
stars. But you can still pick it out as it is somewhat by itself, just to the right of
the two bright stars in the head of Draco the Dragon.
Looking at the Keystone lying on it’s side, the two stars that form the narrow end of
the keystone on the right, are Zeta and Epsilon Herculis, with Zeta being at the top, shining
at magnitude 2.8. The larger end of the Keystone to the left is outlined by Eta and Pi Herculis,
with Eta being on top, glowing at magnitude 3.5. So let’s look at those top two stars,
Zeta Herculis on the right, and Eta Hercules to the upper left. This is how I always have
found M13 right back to the ‘70s: using a finderscope or even better, a pair of binoculars,
look about 2/3rds of the way from Zeta to Eta, and you will see a 5th magnitude fuzzy
star. Point your telescope there and you will spy one of the most magnificent globulars
in the heavens: Messier 13.
One of the reasons M 13 appears so large and bright is that is relatively nearby, only
about 25,100 light years away. Some sources claim that M13 contains over a million stars.
The night sky seen from a planet near the center of of this globular cluster would be
filled with thousands of stars brighter than Venus and Sirius!
Right next door to M13 is our second globular target - and we’ll head there right after
this.
Messier 92 is a modest globular, and it if were not situated so close to it’s big brother,
it would be more appreciated I think. M92 is only 6 tenths of a magnitude fainter than
M13, glimmering at magnitude 6.4. it’s located to the left of the Keystone, so our star hop
will start on Pi Hercules, the lower left star in the Keystone.
From Pi, you’ll immediately see e Herculis at magnitude 4.5 to the lower left. Now move
about 2 1/2 degrees to the upper left and you’ll find 5th magnitude V819 Herculis.
Now move another 2 1/2 degrees the same direction and a little upward, and you’ll locate M92.
As I mentioned, this impressive globular cluster deserves more attention than it gets, but
it’s totally outclassed by M 13, to its southwest. M 92 is harder to locate than its
more famous cousin, but it’s still a splendid object, visible to the naked eye under very
good conditions. It’s definitely a showpiece in optics of every size. M93 is 2/3 the size
of M13, with an angular diameter of 14 minutes of arc.
Now we’re going to slide about 40 degrees to the south, into the constellation of Serpens,
for our next globular target.
Messier 5 is probably one of my favorite globular clusters, because of the snaky way its outer
stars spill into the darkness of space around it. Many amateur astronomers think that M5
gives the great M13 a run for its money. It also lies about 25,000 light years away, and
shines at magnitude 5.7 - a tenth brighter than M13! It’s also a tenth of an arc minute
larger than m13? So why isn’t this contender standing on the top level of the podium? Well
it is definitely is not as rich; containing only several hundred thousand stars. Only!
Our starting point on our search for M5 is the brightest star in Serpens, which has a
funny name: Unukalhai, which means “the serpent’s neck”. But it’s bright, shining
at magnitude 2.6. So center your scope on Unukalhai. Make your first move about 6 degrees
to the right, to 5th magnitude 10 Serpentis. Now move 2 1/2 degrees to the upper right,
and you’ll find the mighty glow of Messier 5. Throw in your high power eyepiece and see
if you can discern how the stars spidering out from the center. I really do like this
globular, and in preparation for this episode, I captured it with the KPO Reflector a couple
weeks ago.
So three great globulars this week. We started with the million star celebrity, Messier 13
in the Keystone of Hercules. Then we moved outside the Keystone to the left, and located
the totally upstaged cousin, M92. Then we zoomed over to the constellation of Serpens,
and saw the heavyweight contender of this Spring Globular show, Messier 5.
Globular clusters are always excellent at public observing sessions, and they always
impress everyone who sees them. This time of year is great with the bright nebulae in
the evenings and the rich globulars overnight. If you stay up until the wee hours, the stars
of Summer are starting to appear, like Scorpius. There’s that time machine again - stay up
late and you can see the next season if stars showing up early!
So that does it for this week’s episode. You can find the show notes on our website
at kpobservatory.org/SH025, where you can comment and leave any questions that you may
have.
We’re planning a big event on our channel coming up this summer in July and August that
I am really excited about. I’ll keep that secret for a couple weeks, so stay tuned for
our big announcement. I think it’s gonna be very popular!
Well thank you very much for for joining me here, and I’ll see you next week in our
episode of Star Hopping.
I'm Cassie, and I hope you've enjoyed star hopping around the Milky Way. We'll continue
to bring you these video astronomy tutorials every week on Thursday, and in their podcast
format on Fridays. They will be designed to help you find deep sky objects that are up
in the sky at the time we post them on the Internet.
The reason we create these video and podcasts is to help beginning amateur astronomers learn
the sky and get more enjoyment out of their telescopes and astronomy in general. If you
have any requests or suggestions of potential targets in the night sky that you would like
to see us present, just let us know down in the comment section below, or on our website
blog.
Don’t miss our free Field Notes for this episode, basically the script of the show,
with all the images and start charts we use for our star hopping activities. You can get
them for free at kpobservatory.org/FieldNotes.
If this is the first time you’re checking out Star Hopping, and if you found this video
useful, please consider Subscribing to our Channel by clicking the Big Yellow Button
down there, click the Thumbs Up on the video, and please share this tutorial out to your
friends who like looking at stars. Also, as I just mentioned, please feel free to leave
any question or comment below, and we will be sure to respond quickly.
Also, please follow KPO on Facebook, where we post all of our astrophotos and keep everyone
informed about upcoming astronomical events. We'd love to hear from you to discuss all
this great stuff up in the sky.
All the links to these places including our website kpobservatory.org, can be found below
in the Episode Notes as well.
And finally, if you feel this video provides you value, and if you'd like to see more,
please consider supporting us on Patreon, where for a small amount per video, you can
support our efforts and let us make even more great astronomy tutorials like this one.
Well thanks again for watching, and we'll see you next time on Star Hopping with Kissimmee
Park Observatory.