Stargazing (Part 2) Ursa Major & Pinwheel Galaxy • Find Constellations at Night, Star Map Guide

Stargazing (Part 2) Ursa Major & Pinwheel Galaxy • Find Constellations at Night, Star Map Guide


How’s it going everyone? I’m Nick and you are listening to the Fresh
Perspective Podcast. If you haven’t yet listened to part 1 in
this series, then what are you waiting for? It gives some great advice on how to plan
and prepare for a good night of stargazing. If you are up to speed, then it’s time to
jump into part 2! To get the most out of this episode, download
it onto your phone, step outside, hold your phone up to your ear, and follow along as
we find and learn about the Big Dipper, the Big Bear (Ursa Major), Bode’s Galaxy, and
the Pinwheel Galaxy. If you are listening indoors, then I hope
you enjoy this dive into mythology and astronomy. This program is brought to you by the members
of the Free Thought Initiative. We help those in need of an inclusive, supportive,
and free-thinking community by hosting public discussions on moral philosophy, healthy living,
and science, to improve the cohesion, health, and scientific literacy of our society. Everyone is welcome, (regardless of personal
religious belief, political leanings, etc.) to participate (in-person) in these open and
civil discussions. To find a Free Thought Forum meeting near
you, to start your own local group, or to become a member and support this program through
monthly donations – please visit freethoughtforum.org. I hope you did your homework from the last
episode because it is time for a pop quiz! Go ahead and locate the Big Dipper. If you are having a hard time, face north. It may be a little to the northeast or northwest,
or it may even seem like it is straight above you. It’s a pretty large, bright, and popular
group of stars, so if you haven’t found it yet, someone else in your party probably
has. Four stars make the bowel, and it looks like
three stars make the curved handle. Americans on the frontier looked at this group
of stars and saw a drinking gourd, large spoon, or ladle. They saw something with which you would serve
up water, or a hearty stew after a long day of pioneering, homesteading, trapping beavers,
or whatever they did in those days. When Europeans see these stars, they see Odin’s
wagon, a butcher’s cleaver, an old medieval plough, and a number of other things. Some Native Americans saw the bowl as a bear,
chased by three hunters. In autumn, these hunters injure the bear,
whose blood turns the leaves red. In classical mythology, this bear wasn’t
a bear at all, but actually the beautiful nymph Callisto, a follower of Artemis (the
goddess of wild animals, the moon, and virginity). Zeus decided that Callisto would be his next
mistress, but knew that she was sworn to a life of celibacy. To get around this, Zeus transformed himself
into a woman who looked exactly like Artemis. They had a romantic encounter. Later Callisto was pregnant and gave birth
to a son, which must have confused her and infuriated Zeus’ wife, Hera. Hera was so angry, that she turned this beauty
into a bear. Years later, as Callisto was living in the
woods, her own son, Arcus, found her! But he didn’t recognize her. He was a great hunter and chased her until
she could run no further. Just as he was about to spear her with his
javelin, Zeus intervened and spirited her up, into the sky. That is how Callisto became the constellation
of the great bear. Her son was also transformed into a bear and
became the constellation Ursa Minor, the small bear, or the “little dipper,” a constellation
we will cover in the next part of this series. In some versions of the story, the constellation
of Boötes, the herdsmen, is actually the boy hunter, Arcus. The asterism of the Big Dipper has different
names all around the world, but it belongs to a larger official constellation known as
“Ursa Major” or “the Big Bear.” The Big Dipper is the bear’s lower back
and tail. There you will find its brightest stars. The other stars of this constellation are
much dimmer. If you start from the base of the tail and
connect the top star of the dipper’s bowl, and then continue to hit the next two stars
in that line, then you find the eye and nose of the bear. It is a fairly skinny bear that looks like
she hasn’t eaten in a while. Below her eye is where her front limbs begin. Can you find her front legs? It looks to me like she is digging. The bear’s back legs are much larger. Start with the bottom of the bowl of the dipper. The back star, closer to the tail, is the
back hip. Ursa Major’s back legs are spread wide like
she’s taking a stand to protect her cubs. Find the next star down just below the hip
and slightly back toward the tail. This is the top of the back legs. The left leg follows the curve of the front
legs, and the right leg is straight down from the hip. Once you find the eye, nose, and limbs of
the bear, this constellation gets pretty big! In fact, it is the third largest constellation
in the sky. Ursa Major doesn’t just look like a bear,
it behaves like one. In the spring and summer, she is high in the
sky and active. But when fall and winter come along, she hibernates
low, along the horizon. The brightest star here is Alioth. You can find it by looking at the three stars
of the tail. It is the first one, closest to the rump of
the bear. When you look at Alioth, you are looking at
a star that is 81 light years away. The second brightest star is Dubhe and is
found at the top front of the bowl of the big dipper, in the middle of the bear’s
back. Dubhe is an orange giant, 123 light years
away. It has a tiny yellow-white main sequence star
next to it and they orbit one another as a binary. In the belly of the bear is the star Merak,
which is just a cool sounding name. The last star at the tip of the tail is Alkaid. Alkaid is one of the hottest burning stars
you can see without a telescope. It is a blue star, about 100 light years away,
and is six times larger than our sun. Now take a look at the middle star of the
tail, the one that makes a kink in the tail. If you have really sharp eyes, or if you take
a look at it with binoculars, then you have probably noticed something odd going on there. This is the star Mizar, but if you look close
enough, Mizar is actually two stars. The second star is Alcor. This is another binary star system, where
two stars orbit a point in space between them, like two partners in a dance. Can you see them both? As we continue our exploration of our first
constellation, go ahead and get your binoculars out if you have them. Better yet, if you have a telescope, get that
ready. A telescope would make these deep space objects
much easier to find. It is time to spot two of the galaxies hiding
in the darkness around the great bear. The first subject of our search will be M81,
Bode’s Galaxy. To find Bode’s Galaxy, we need to zero in
on two stars in the big dipper. Look at the bottom of the bowl of the dipper,
to the back star closer to the handle. That star is “Phad” with a “Ph.” Now find the diagonal star from it, forming
the upper front edge of the bowl. That is our friend Dubhe again, the orange
giant. Now if you connect those two stars and follow
the line they create, you will run into M81, one of the easiest galaxies to see. The distance from the big dipper to the galaxy
is about the same as the distance between Phad and Dubhe. Double the length of that diagonal line, and
you’ll find it, a bright smudge in the darkness. Bode’s Galaxy is about 12 Million Light
Years away. Compared to other galaxies, that isn’t that
far, making it easier to see in comparison. It belongs to our “Local Group” so, in
cosmological terms, it is just down the street from the Milky Way. It’s about half the size of our galaxy and
has 250 billion stars, but the black hole in its center is 15 times larger than the
black hole in the center of the Milky Way. Just like Ursa Major, it is easiest to see
in the spring. To wrap up this part of the sky, I have a
challenge for you. In these episodes, I think it would be fun
to see if you can find some of the more difficult objects to see. Your challenge tonight is to spot the Pinwheel
Galaxy! The Pinwheel Galaxy (M101) is one of the most
popular spiral galaxies in our sky. Finding it can be pretty tricky at first,
and will probably take you a few tries. Through your binoculars, it will be a blurry
patch. Through your telescope, you will be able to
spot its bright center. Find the last two stars in the bear’s tail,
Mizar and Alkaid. These form the two bottom corners of an equilateral
triangle (or a triangle with all three of its sides being the same length). The top point of this triangle is invisible,
but if you look with strong binoculars or a telescope, it appears. The Pinwheel Galaxy is just about where the
tip of this imaginary triangle would be. You can think of it as a fly, pestering the
tail of the great bear. The Pinwheel Galaxy is about 20 million light
years from Earth, and it hosts many young bright stars. It is asymmetrical. This is probably because it crashed into another
galaxy and absorbed it in the distant past. It is 70% larger than our home galaxy, is
found beyond our Local Group, but is still in our neighborhood. It is a member of the Virgo Supercluster,
along with our Milky Way and the Andromeda Galaxy. For all of you who can find tonight’s challenge,
be sure to let us know in the comments! If you have enjoyed this conversation or have
learned something from it, please leave a like, subscribe, and share it with other open-minded
people. All of those small things really do make a
big difference and help others find our group and our podcast. That is all I have for you today, but the
conversation continues across social media and in the comment sections below. Do you agree with today’s message? Am I mistaken about some detail? How can I better elaborate on this topic in
the future? Feel free to share your perspective!

1 thought on “Stargazing (Part 2) Ursa Major & Pinwheel Galaxy • Find Constellations at Night, Star Map Guide

  1. Love the stargazing videos. Want to get me friends into stargazing and astronomy in general. Keep up the wonderful work

Leave a Reply

Your email address will not be published. Required fields are marked *