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Aquila the eagle constellation can be a fairly easy one to find
if you know what the pattern is and different ways to find it.
I will always encourage you to seek out dark skies if possible when trying to
find the constellation. Aquila's brightest star is called Altair
and it is part of the Summer Triangle asterism.
In this video, we will explore this bright star called Altair.
We will look at its distance, spectral class, and shape.
Altair is the Alpha star of the constellation Aquila, which means it's
the brightest star in the constellation and it's the 12th brightest star in the
night sky. It's estimated to be 16.7 light years
away. Altair is a type A main sequence star. When I say type A
I mean that's its spectral class. It has
a whitish blue appearance to it. When you compare it to
the size of the sun, it is bigger than our own sun, but its shape is different.
It rotates really quickly, every nine hours.
When this happens it gives it kind of an
oblong shape and you can kind of compare that
when you look at our own sun. Our sun rotates every 25 days
where Altair rotates every nine hours. So, because of the quick rotation of this
star it's more oblong along the equator
and a little bit flattened at the poles. There are other stars that are like this
as well, but when you compare it to our own sun it definitely
is different.
Altair is also one of the very few stars in which we've been able to gather
a direct image for. There's only a list about two different stars in which we've
been able to capture a picture of. Here you can see this is what Altair
looks like and there's been some grid lines drawn on
it to see where its polar region is in comparison with
the equatorial region. Hopefully you can see how it has
that oblong shape to it. This was taken by an optical
interferometer on the CHARA Array on Mount Wilson
in California. So, Altair is a really special star in
its shape and the fact that it's just really close to us, so it really stands
out in our sky. Here we have the official star
map of Aquila. As you probably noticed,
when you look at it, Altair is the star that stands out from
all the rest of the stars in this particular constellation.
This for me was what made it really challenging to find Aquila simply
because Altair was really the only star i was able to
see. Now as I moved throughout my life and
found darker skies to stargaze in, I was able
to point out this constellation. But where I grew up
there was a lot of light pollution, so I was only ever
able to find Altair and you may have that experience as well.
I was able to find this gorgeous picture of Altair
and the two stars that surround it. So this would be
like the head of the eagle and then this would be the neck of the bird
as well. I love this photo because it's a long exposure photograph.
A lot of the dust and gas from the Milky Way really just shines through in this
photo. So let's take a moment to surrounding it to just
explore Altair and the other two stars that are surrounding it.
So Altair is a whitish blue star. It's classified as an A star. That's its
spectral class. The reason it's so bright in our
skies is because it's only 17 light years away.
Its name was derived from the Arabic phrase meaning
the flying eagle. Tarazed, the one that is close to Altair,
is an orange star that's estimated to be 460 light years away.
This name was derived from an Arabic phrase meaning the balance
Then, Alshain. This one's the faintest of the three.
It is a yellowish star that's only 45 light years away,
so it's not as close as Altair, but it's not as far as
Tarazed. This name was also derived from an
Arabic phrase meaning the balance. As I was researching Altair I came
across some beautiful poetry I wanted to share
with you. This was written by Karle Wilson Baker
in 1919. Three of them walked together
Joyous and fair and high,
Through the still, heavenly weather
Up in the summer sky Under their feet are the fountains
The night- bird's heart outpours
Flooding the mimic mountains of
Of the shadowy sycamores Over the sky forever
She leadeth her comrades sweet;
No dream of our mortal fever
Troubleth her straying feet
She lifteth the ears from my shoulders, She looseth the weight from my wings;
Long hidden from all beholders An old sealed fountain sings
Three of them walk together-
She is the fairest of the three;
And sweet as the heavenly weather
She maketh the heart of me!
I simply love this poem because it describes
a lot of the feelings that I have when I
go out and stargaze. First, she lifteth the years from my shoulders.
This is exactly how I feel anytime I go outside and stargaze. I just
look up, I forget about what's going on in my
life and I'm able to just enjoy the beauty of nature. She also
references the three of them walk together, which I
believe she's referencing these three stars together- how they kind of
form a line. And it also references
when exactly you can see this particular star, which is
up in the summer sky. I hope you enjoyed this
small little poem that references Altair. I love when science and art can meet
because to me those are the things that inspire me the
most in this world. First let's review how we can find
Aquila and its Alpha star called Altair. In this photo the three
brightest stars are part of what's called the Summer
Triangle. This triangle shape is the main way to
find Aquila. The brightest star, right here,
is Vega and it's part of the constellation known as Lyra.
The second brightest star in the Summer Triangle is
Altair. So, if you can find the brightest star,
try to find the second brightest one and that one is Altair.
The third star, right here, is called Deneb and that's
part of the constellation known as Cygnus.
So first we'll point out where Aquila is. Aquila has the head, right here, with
Altair as the eye of the eagle as I like to think of it.
It has the neck of the bird and then the wings to the side.
Thee other constellations, if we point them out are, right here.
So you have Lyra the harp with its bright star Vega,
and then Aquila, the bright star Altair, and then Cygnus right here with the
bright star of Deneb. So let's get a little bit more
practice with being able to find Aquila and Altair with a little more
realistic sky. This is a little bit more of a version of
what you may be seeing and even this could be optimistic
in terms of what you may see in your local area.
First thing that you want to do when you look at this photo
is, can you find the three brightest stars?
For me they are right here and that's what makes up
the Summer Triangle. If we go backwards here
can you find the brightest star in this picture?
It is kind of a tie between this one and this one,
but Vega is right here and I can tell because of that tiny little
constellation of Lyra. And then this one would be
Altair. So if we were to point that out, there's the Summer Triangle,
and then Altair is a part of Aquila the eagle. This is
one version of what this constellation pattern looks like.
If we were to point out everything else here, which would be helpful
since you need to know the other constellations around Aquila to help you
find it. This is what we have. We have Aquila down
here. We pointed out lyra before. Then here
is Cygnus. Cygnus has a long body with the long
neck and then the wings of the bird to the side.
Delphinus is another great way to find Aquila because it has this this tiny
little shape a parallelogram or diamond shaped head with the tail the
Sagitta the arrow is right here. Then, Hercules is nearby as well as
Draco. Try to use these different
constellations to help you find Aquila. We've come to the end of our
video about Altair the brightest star in the
constellation Aquila. I hope it was helpful for you, and to
find different ways to find Aquila, and to learn a little bit more about
this particular region right here and the stars that are located next to
Altair. Remember, this is a constellation that
can be challenging to find. If you live in areas with lots of light
pollution.For years I was really only able to see
Altair and I wasn't quite able to point out the
entire constellation.But now that you're familiar with it I
hope you're able to find it. Remember it takes time patience and
practice to find the constellations. I wish you luck and keep looking up!