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and classes released each season. Welcome my name is Janine! In this
video we will learn about the meteor shower known as the Perseids
which occurs from mid-July to late August. The peak of the shower happens
around mid-August. So, we will discuss why meteor showers
occur and get practice with identifying the constellation
of Perseus, since that is the radiant for this meteor shower.
The Perseids is a great meteor shower to observe because it's fairly consistent
each year with the amount of meteors that can be
seen. It has a long duration from mid-July to late August, even into
September. For the year of 2020, the peak nights
happen around August 12th. The showers are best
seen really early in the morning and the moon phase is a Waning Gibbous,
so that gives it pretty ideal conditions in order to
see this meteor shower. I definitely recommend that you try to
move away from city lights and light pollution so you have the best
opportunity to see these colorful streaks across the
sky. This shower is associated with the comet
known as Swift Tuttle. Meteor showers occur
because the Earth passes through an area of debris called the Perseid Cloud
and then it stretches along the orbit of the comet Swift
Tuttle. When comets come around the Sun,
the dust that they emit spreads into this
dusty trail around their orbits. Each year the Earth passes through
these dusty debris trails and these particles
enter our atmosphere where they burn up and create beautiful streaks across the sky.
Let's take a closer look at the comet known as Swift Tuttle,
since this is a comet that's associated with the Perseids.
It was discovered in 1862 independently by both Lewis Swift and Horace Tuttle.
This diagram shows you the orbital path of comet Swift Tuttle. Its last
approach, right there, was in 1992. It will return again
in 2125. What I want you to notice about this diagram is the path of the comet.
First, it's really a wide ellipse and it's very long. As it approaches
the sun it speeds up. Then, as it moves away from the sun
it starts to slow down. Also, when the Earth passes through
this orbital debris, right here, that's when we have
meteor showers. So, we're not likely to see
comet Swift Tuttle in our lifetime, but we
can see the effects of it as the Earth passes through
its cloud of debris.
As we learn more about meteor showers, it's a good idea to really get a clear
definition of what a meteor is. A meteor is an
object that glows due to friction, while traveling through the Earth's
atmosphere. It appears as a bright streak of light in the sky.
Here's a great photo of a meteor passing through Earth's atmosphere. This was
taken from the International Space Station
during the Perseids meteor shower. This is a great diagram that shows you
the differences between meteoroids, a meteor, and a meteorite. A
meteoroid is a small rocky body in space. A meteor is when it passes
through our atmosphere. When it makes an
impact on the surface of the Earth it's a meteorite.
So, meteor showers are celestial events that occur
as the Earth is passing through that cosmic dust and debris that's left
over from comets. They typically are named
after the place they appear to originate from in the sky.
For example, the Perseids originate from the constellation
known as Perseus. Here is another great photo taken during a meteor shower over
a course of a few hours. You can tell this was taken during a
meteor shower because you can trace the streaks of light back to one
origin point in the sky, which I would say is probably right around
this area. Because meteor shower particles are traveling in parallel
paths in space at the same velocity, they will all appear to an observer to
radiate from a single point in the sky. However, this effect is best seen in
photos rather than when you're observing. So, let's look at this effect a little
bit more deeply. When you're
observing the meteors in a meteor shower, they will appear randomly in the sky. But,
if you trace them back they have a common point
of origin. That's called a radiant. They are often named after the
place they originate from the sky for meteor showers. Again, we're going to
use the Perseids as an example for this. Here,
this is where the radiant would be for the Perseids. It appears to come
from the constellation Perseus. Let's take a look at a few more
time lapse photographs of meteor showers. This
one here is a four hour time lapse picture of a meteor
shower. You can easily figure out where the radiant is which would be this
area. If you trace all these streaks of like
back to the origin point they all come from this
area. In the second half of this video, I want to teach you how to find Perseus.
It's best seen in the Northern Hemisphere during the Autumn months and
early Winter month. For the Perseids meteor shower, you have to go out and see
it in the early morning and that's when
Perseus is rising, mid- July into August.
You want to look
for star clusters near the constellation of Cassiopeia and
Auriga. As you look at this photo, can you see those little clusters of stars?
There's two of them. One is right here, this is a double cluster. Here is
another cluster of stars. You can also use the Pleiades star
cluster to find Perseus. Pleiades is that cluster in the
constellation of Taurus and Cassiopeia which is a very
easy constellation to point out. Go see that video
if you need more information on how to find Cassiopeia.
You can use it as a pointer. There are many variations of this star pattern
that I've seen in books. So, I'll show you the official
star pattern and point it out for you right now.
Here we are. This is the head of Perseus.
He's represented as a hero in Greek mythology.
You have his arms right here, his body, and then his legs
right there as well. Now, there are star clusters that I use to help me figure
out where Perseus is. The pattern doesn't always stand out to me in the
sky but those clusters I can find really easily.
The first one is right here. This is Alfie
Persei. That's a cluster within here and then there's also a double
cluster up here. So let's take a look now at the official
star pattern. Here we have it. I want you to notice
some of the constellations that surround Perseus. We have Cassiopeia
which you can use to kind of help point you in the direction
of Perseus. You have Andromeda. Down here we have Taurus. I often use the
Pleiades star cluster to help me find Perseus.
Then, you have Auriga which is the charioteer.
There's lots of constellations that stand out
that can help you find where Perseus is. If you want to get a different
viewpoint of what he looks like in the sky- here
you can see his arms and then his one leg looks a
little shorter than the other. I am just warning you that there are a
lot of different versions of what Perseus looks like
if you would open up different books and and that's okay.
This one is from the International Astronomical Union which
is considered to be the authority in terms of star patterns.
Let's get some more practice with how to find Perseus in the sky.
So, as you're looking at this photo there's three things that probably are
standing out to you and those are three clusters. The first
one, right here, is this bright cluster. That's the
Pleiades star cluster located in the constellation of Taurus.
It's pretty easy to see with the unaided eye
and you can use it to help you find Perseus. The other two things I want you
to notice is this star cluster right here and this
one right here. This top one is a double star cluster
and this, right here, is the Alpha Persei star cluster. I don't
always have an easy time pointing out the constellation pattern of Perseus,
but I can really easily find these two star clusters. If you live in an area
that has a lot of light pollution this might be a challenge
for you to find this constellation, but you can
also use the other brighter star constellations
to help you find Perseus. If we were to point out
the constellation ,that's what it looks like. You can also see there's another
little star cluster right here. But, you have the head of Perseus,
his body legs, and his arms. Let's continue to get more practice. So,
what is it that you notice about this constellation,
or this photo, I should say. First, there's two things that stand out to
me immediately. One is this bright star here and then this star cluster right
here. This one is the Pleiades in
Taurus and this is Capella which is in the constellation of Auriga.
Then Perseus is right here. Can you find those two little star
clusters I mentioned? So here you've got one. Here you have the
other. There's also a portion of Cassiopeia.
It's not the full constellation but four out of the five stars.
So, you can use Cassiopeia to kind of direct
you towards Perseus. If we were to show you where Perseus
is- that's the star pattern. You've got the one double
cluster that's located closely to the the head of Perseus and
the other objects of importance are Capella,
you have the Pleiades, and Cassiopeia. Down here, you have Andromeda and here is
the Andromeda Galaxy, an awesome galaxy, that can be seen with the unaided
eye. Let's look at one more photo to help
give you some practice with how to find Perseus. This picture is a little bit
more of a realistic view of what you may see in the sky as
opposed to the other amazing photographs I've showed you
earlier. So, as you're looking at this photo
what stands out to you? For me, the first thing I notice is this star cluster
right here. Hopefully at this point you're
recognizing that this is the Pleiades and it's in the constellation of Taurus.
If you want to learn more about Taurus and the Pleiades go see
that video. The other thing I notice is this bright
star right here. This bright star is Capella that's
in the constellation of Auriga. It's a little difficult to point that
out, but I'll show you in a moment where it is. Then, I also notice this
star cluster. This is the Alpha Persei star cluster and this is the
major way in which I can find the rest of the constellation.
So, if we were to point it out, that's the pattern of
Perseus. You may also notice some streaks in this photograph, these are meteors
that are traveling as this photograph was being
taken. So, if we were to point everything else out down here we have the Pleiades,
as we mentioned. This is the star pattern of Auriga.
When I view Auriga I often see this pattern. I learned it this way
as opposed to the official star pattern here. If you want to learn
more about Auriga go see that video as well.
We have Triangulum the triangle constellation.
This right here is a portion of Aries, it's not the full constellation
the rest of it is off the camera. So, I do hope that this was helpful for you.
I wish you luck when you are trying to view the Perseid meteor shower.
Now you know why we see meteor showers; how they're named;
and for the Perseid shower, how you can find the constellation
Perseus. Remember that it takes time patience and practice to stargaze and
view celestial events. I do hope weather is
on your side and you have cloud-free skies.
In 2020, when this is being recorded, the moon phase will be in a Waning Gibbous
phase which makes it ideal conditions for viewing the
Perseids. The peak in 2020 is August 12th
and the best time to view this shower is around 4 A.M., so really early in the
morning. Good luck trying to find this
meteor shower and remember keep looking
up!