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and check out our online courses. Welcome! My name is Janine and in this
video we'll learn about how to find the constellation known as Canis Major. Canis
Major is an ancient constellation and the earliest records date back as far as
from Mesopotamia. It was included in Tomi's 48 constellations in the second
century and is still counted among the 88 modern constellations. The name Canis
Major is Latin for greater dog and it's classified as a seasonal constellation.
It's best seen in the winter months in the northern hemisphere. Canis Major is
fairly easy to spot due to the bright star known as Sirius. Sirius is the
brightest star in the night sky. It's also fairly close to us in distance when
compared to everything else, so knowing this it helps you be able to spot Canis
Major. What are the best ways to find it? You want to be able to use Orion.
Orion is one of the most recognizable patterns in the winter sky. Here's Orion
and you want to use the belt stars, right here, to lead you down towards Sirius. The
star Sirius is part of a winter triangle asterism. Remember an asterism is not
a true constellation, but a pattern that helps you identify other constellations.
So, the winter triangle includes Sirius, Betelgeuse guys located in Orion,
and Procyon in Canis Minor. The Milky Way also runs through a portion
of Canis Major, so this is a great opportunity for you to find some
interesting celestial objects within this constellation. Let's examine a
couple legends that are associated with this constellation. Remember there is
no one true constellation story for any star pattern as the legends of the stars
vary depending upon the culture and place. In Greek mythology, the legends
of Canis Major are complex. Virtually every dog featured in greco-roman
mythology has been associated with this constellation. Canis Major along with
Canis Minor are often identified as Orion's hunting dogs and this makes
sense since they're situated so closely together in the sky. One of the main
legends about Canis Major is that of the mythological dog known as Laelaps this
canine was said to capture anything that it hunted. Laelaps was a gift from Zeus
to Europa and has also been identified as the Hound of Procris. King Minos
also possessed this dog at one time too. One of the most well-known stories
is that of the teumessian fox. In one myth Cephalus took this dog to Thebes to hunt
down a fox that was causing some trouble in the area. This box was extremely fast
and was destined to never be caught so once Canis Major or Laelaps found the
fox and started chasing it the race would appear to never end, because canis
major was able to catch whatever it hunted. But the teumessian fox was
able to avoid capture. Zeus himself noticed this
happening and he finally ended the race or the chase, I should say, and turn
both animals into stone. Then he placed both the dog and the fox in the night
sky for us to remember them by. Here we have Canis Major, Orion is right
here, and then this is Canis Minor. It's possible that Canis Minor was once
identified as the fox in this story. Now let's review the pattern that Canis
Major makes across the skies. Here is the official star pattern or star map
that's released by the International Astronomical Union. These boundaries of
the constellation were designated in 1930. When you're looking at this map
the obvious thing that you probably notice is the big black dot near the
center of this map. That big black dot is Sirius and that tells you that
the star is very very bright. When you compare it to many of the other
stars Sirius really does outshine most of the rest of the stars in this
constellation. Let's get a look at some pictures that we have. Here
there's multiple constellations in this photograph. You probably notice the
really bright star towards the center of the photo- that of course is Sirius.
From there you want to be able or try to point out the star pattern of Canis
Major. We'll point it out in a bit, but notice that Orion is towards the right
side of this photograph. I want you to be able to use the three belt stars
of Orion to point you towards Sirius. So, what does this star pattern look like
with the photograph? There it is. It is one of the few constellations
that somewhat looks like what it's supposed to represent. Leep in mind
that the star patterns of constellations really can vary depending upon the book
or resource that you're looking at. I
haven't seen one constellation that has the same pattern except- I would say
maybe Orion. Let's point out where Orion is as well. Then the other
constellation that's located here is Lepus. Lepus is a rabbit and it's
located right underneath Orion. Then you can use Canis Major to help you
find this constellation as well. So, here we have another picture of the winter
sky. What I'm hoping you'll notice is the winter asterism known as the winter
triangle. Those are the three brightest stars and they make that shape
of a triangle. These three stars are pretty easy to identify even at a sky
with lots of light pollution. Again use the belt stars of Orion to help you
find Canis Major. The whole constellation is not visible here but
you can at least get a general idea of where it's located. Then from here I
always try to look for the triangle-shaped head that's located next
to Sirius. Sirius is often dubbed the heart of the dog as well. Here we have
another look at a star pattern or a picture. Again you should immediately
notice the winter triangle. That asterism will help you identify other
constellations. So we have Orion right here, we have a portion of Canis Major,
and then this little 2 star constellation is Canis Minor. The
stars that make up the winter triangle are Sirius, Betelgeuse, and Procyon
sometimes called Procyon.
Sirius is also part of another asterism called the winter hexagon. Instead of
the triangle you can use this winter hexagon to find the other bright stars
in the winter sky. When we're looking at this large sky view of the winter sky-
hopefully you can see that there are a collection of bright stars that are here,
not to mention some celestial objects. When we're trying to look for the winter
hexagon here, it is traced out for you. This is where the winter
triangle is as well. Keep in mind that you may not be able to see the winter
hexagon if you don't have an unobstructed view of the entire sky. This
is a really really large picture that covers a good portion of the sky. Another
thing I want you to notice is this hazy area right here this is the Milky Way
galaxy. Part of the Milky Way does run through Canis Major
so if we point out other constellations that are here- we've got
Gemini, we have Auriga, Perseus is right here,
here's Taurus- you can tell because of the Pleiades, of course you should know
Orion at this point. Orion points down to Canis Major, and then you use the
shoulder stars of Orion to point you to Canis Minor. Now let's examine the bright
stars of Canis Major. Of course we have to start with Sirius, which is the
brightest star in this photograph. Sirius is actually a binary system made
up of Sirius A and B. Sirius A is classified as a white main sequence star,
while Sirius B is a smaller white dwarf star. These two stars revolve around each
other every 50 years and they're only 8.5 light-years away. This system is also
the fifth closest stars to the earth and the name itself is derived from the
Greek word Seirios which means scorching or glowing.
This name however may have actually derived from a more ancient Egyptian
word. Sirius played a really important role to the Egyptians. The Nile River was
said to overflow at the time of the year when Sirius rose at daybreak. This
flooding re-fertilized the field surrounding the Nile and this time
was counted as the new year for Egyptians. Another story I read about
Sirius is how ancient cultures may have thought that the heat from Sirius added
to that of our own Sun making it a scorcher of a star. Remember Sirius
is in the daytime sky during the summer months. I find this really interesting
especially since Sirius is a very closed star to us. So if we take a look at
Sirius with some magnification- this is what the star would look like through a
telescope or binoculars. However, when I view it through binoculars it's really
bright and it doesn't feel too good for my eyes. When we use a telescope like
the Hubble Space Telescope, which took this picture, we're able to see the two
companion stars here. So, this is Sirius A, the white main-sequence star. and this,
right here, is Sirius B, the white dwarf star. In this picture you're not able
to determine the difference between the two binary stars. It's only when we
really have a high-power telescope like the Hubble. If we want to do some
size comparison here. When we look at the size of the Sirius system with our own
system, we can see that Sirius A is larger than our own yellow Sun, but when
you look at Sirius B the Earth is slightly larger than it but not by much.
One star I'd like to discuss that you can't necessarily see with the naked eye
but it is located in this constellation is called VY Canis Majoris. It's one
of the largest stars known in the Milky Way galaxy. It's a red hyper giant star
and it's very oxygen-rich which definitely tells us that it's a large
star because oxygen is one of those final elements to fuse in a star. Silicon
would be next and then iron, but it is just a gigantic star. It's radius is about 1,400
times that of our own Sun. This star lies at approximate distance of
3,900 light-years away and it's a variable star which
means that it's magnitude changes over time. Sometimes it's magnitude is about
6.5 and then it could dim to about 9.6. Now the human limitation for
seeing stars with the naked eye is about magnitude of 6, so if
you want to be able to see this with the naked eye you would need some
magnification. Hypergiant stars are just ones that have incredible masses
and they lose their mass at a very high rate because they're just burning
through their fuel really really quickly. If we
were to take a look at a size comparison here- here is VY Canis Majoris
this little area- that's the Sun right there. Compared to
this hyper giant star it's like the sun's like one little
pixel here. It's just an incredibly large star. It used to be thought of as
the largest star, but since then we have found other ones that are larger and
this one is located inside the boundaries of Canis Major.
In the final part of our video, we review the celestial objects that can be seen
in Canis Major. So, here it is. We've got the different objects located on the
star map. All of these are open star clusters. These objects that I pointed
out for you are easy to see with the unaided eye if you have a really dark
sky or they're easier to see if you happen to have a telescope or a pair of
binoculars. All three objects that I circled here
are open star clusters. They're often located in the arms of the galaxy and
consist of younger bluer stars. They are also younger in age as well on the order
of millions of years as compared to billions of years which globular
clusters are usually older stars. Now there are other objects besides these
open clusters to view. You have some nebula here, and these are galaxies. But,
You would really need a high-power telescope to observe any of these
because their magnitude is either of 9, 10, 11 or more. We've come to the end of
our video. So, let's review everything we learned about Canis Major so far. Canis
Major is represented as a great dog and it's best seen in the winter months. It's
is classified as a seasonal constellation. The best way to find it is
to look for the three belt stars of Orion right here. Then,
make a diagonal line right down to Sirius. It's really hard to not find
Sirius just because it is the brightest star in the night sky. Some of the
objects that you can see are M41, which is located right there, and
a few other star clusters located in this
region. I wish you luck finding this constellation. It's one of the few that
somewhat looks like what it's supposed to resemble. I encourage you to seek
out dark skies so you can see some of the cool celestial objects that are
within the Milky Way that run through this constellation. Thank you so much for
watching and good luck!