Welcome to Learn the Sky, your online resource for learning about the stars and constellations.
Welcome, my name is Janine and in this video we're going to celebrate and discuss the landing of the
Mars Perseverance 2020 Rover on the surface of Mars in Jezero crater. This is very exciting
because there are so many different technologies that are going to be tested on this particular
mission, and even though this is a departure from my typical videos about stars and constellations,
the planets are still observable objects in the sky and I personally love learning about them. So
let's get started. The Mars 2020 Rover blasted off into space this past July of 2020, and even though
that happened seven months ago this mission has been well in the works for over a decade.
So after it launched it went into the cruise part of this mission, and it took seven months for Mars
Perseverance to reach Mars and on February 18th it entered the entry descent and landing portion
of this mission, and this is what NASA scientists called the seven minutes of terror, because
anything can happen during this time, and Mars Perseverance was scheduled to land in Jezero,
crater. What's interesting about the Jezero crater is that it was once a standing body
of water, and when we study Mars we have to follow the water. Where was water once existed and in this
particular mission what I find really interesting is that they're going to be collecting samples
of the martian terrain that will eventually be returned to Earth, and my favorite part of
this entry descent and landing is the sky crane maneuver, and this maneuver was used before on the
curiosity mission. There are no longer any bouncing rovers. The bouncing rovers was something I loved
seeing animations of with spirit and opportunity, but now the sky crane maneuver is being used. So
it's very very exciting that this is where we're at. We had our first successful pictures from the
Perseverance Mission. So the surface mission is broken down into different parts. The first is that
they're going to be collecting these core samples about the size of a piece of chalk, and we're going
to collect this box of rocks, and eventually return it to Earth where we can study it in more detail,
because in reality we're not really able to take large sophisticated equipment to Mars. We have to
make it compact. We have to make it sturdy, and fit on something the size of a Mini Cooper, and that's
how big Mars Perseverance is about the size of a Mini Cooper, and on February 18th we saw the first
picture from perseverance. It's a little grainy, but that's mostly because of the dust that was
kicked up as it landed on the surface. Snother exciting piece of this journey is that there will
be a helicopter on Perseverance, and this will be doing some scouting and and collecting some
data that is needed for scientists, and this is just a precursor for many other missions.
So when humans eventually travel to Mars it will be important to have helicopters like these
to travel around and scout out different areas before humans even go there, and there really
are some challenges with creating a helicopter that can work on Mars, because the atmospheric
pressure is just so different, and we're gonna talk a little bit about that. So anything that
I talk about on Mars I'm always gonna reference what is on the NASA Mars 2020 website. Which I'm
going to put a link for that in the information below, so you can check it out because really I'm
not going to recreate what NASA does. They do an incredible job putting information out there for
the general public to view. So definitely check that out, and I just have to give a shout out
to all the scientists out there that were a part of this mission. There really were thousands of
people that helped put this together, and in the middle of a pandemic, right towards launch period
is when the pandemic happened and these wonderful people were able to get everything done that they
needed to get done, and it really is inspiring. So we really are just at the start now of this
surface mission, so it's going to be exciting to see what comes out of it over the course of time.
So in the next portion of this video what I want to go over with you is just some basics about
Mars, and where exactly it is in the sky in the time that this video was made in February of 2021.
At the time of this recording the best way to find Mars is to look for the Pleiades, and also follow
the moon. So you really have to know where to find Taurus. Taurus is where the Pleiades star cluster
is located, and this is where Mars is in relation to the Pleiades. So hopefully if you have clear
skies you're able to find it. I do have an upcoming video on the Pleiades, and I have a video about
Taurus so be sure to go see that video, but I'd like to share just some broad facts about Mars.
Mars is a planet that is half the size of Earth, and it's known as the fourth planet from the Sun.
It got its name from the roman god of war, and Mars is interesting because
even though it's half the size of Earth there are some similarities there.
It has an axial tilt of 25 degrees, which is similar to what the axial tilt of the Earth is.
Earth's axial tilt is 23 and a half degrees, so the fact that it has this tilt it has
seasons just like Earth does. Its atmosphere is primarily made of carbon dioxide, and the very
big difference between Mars and Earth is that Mars has no magnetic field. So this poses some
challenges for when humans eventually land on Mars. The fact that there's a carbon dioxide atmosphere,
so we're either gonna have to take our oxygen with us or find a way to create oxygen but there's also
no magnetic field. Another challenge is that since Earth is smaller it has let, or I'm sorry since
Mars is smaller it has less gravity. So that's one of the reasons it's not able to hold those
heavier elements like oxygen and nitrogen, like Earth has. Also it is estimated that water does,
has existed in the past on Mars. Scientists have found features that are very similar
to what we found on Earth that suggest water was present, but until we collect those samples
from Mars which will really be happening and it won't be happening for quite a few years that we
we really need to look at detailed analysis of the soil to see if there was once water there and if
there are any bio signatures there. I also think a little fun fact is that the largest volcano
in the solar system is located on Mars. It's called Olympus Mons, and it does have two moons
that were once captured asteroids called Phobos and Demios. In the next portion of this video I
want to provide you with some strategies with how to view Mars and the other planets. So as you
take a look at this photo what stands out to you? For me there's about three things that stand out.
First is definitely the Milky Way, which is right here, it takes up a large portion of this photo,
and then there are a few meteors that are traveling through this photo as well, but the final
thing right here is this planet which is Mars, and how do I know it's because of its reddish color.
You'll also notice that the motion of the planets are different than that of the stars. The stars
have a predictable, regular motion and we know when we go out at this particular time that we will see
this star at this time of the year. Well that's different for planets. So in order to understand
this you have to understand the definition of a planet, and the word planet is traced back to
the ancient Greeks which means wandering stars, and they named it that because the motion of the
planets didn't follow that of the stars. We would see that they would move backwards in the sky, and
then they would move forwards, and then it would go backwards again, and this plotting here
of Mars really is happening over the course of many months. So it's important to understand that,
and that planets got their names from wandering stars. So the other thing that I want you to notice
is that this is very bright when you compare it to all the other stars. The apparent magnitude of Mars
is negative 2.9, and the the apparent magnitude of the brightest star Sirius is negative 1.5. So Mars
is always going to be brighter than all the other stars, and it's going to have that reddish tint.
If we were to zoom in on mars using a telescope this is what it would look like, and if you have
any questions about apparent magnitude or absolute magnitude I have a video on that, so be sure to go
check out that video, but this picture here shows you what Mars would look like through a telescope,
and what's interesting is you can see different colors here, you can also see one of the ice caps
here, so it's really amazing to look at Mars through a telescope. I have had the opportunity to do it and
it it never disappoints for sure, and I wanted to show you some other pictures of Mars as well,
so you can just get that experience with learning how to recognize it. So I'm sure you can find it in
this photo. Here we have a picture of a comet, and then you have this picture right here of Mars near
the comet, which is really fascinating and you can clearly see that that is a disc in
the sky. If we get some more practice here, here's another photo. So here you're actually looking at
two planets. So are you able to tell which one is Mars? I can because Mars always has that reddish
color, and remember the the martian soil is reddish in color because of iron being oxidized. So that
tells us that oxygen was probably present at some point in the history of Mars, but Mars is located
right here and then this other planet is Jupiter. So I like this picture because it shows the
magnitude of both objects, and Mars appears to be a little bit brighter. So keep in mind that
magnitude can really change also with atmospheric disturbances, but this gives you a good comparison
between Mars and Jupiter. I actually have a picture that I took of Mars. This is not a really great
quality picture. It was taken with an iphone, but you can probably point out where Mars is.
It's the brightest spot on this photo, right there, and here is where Capricornus is. I remember when I
took this photo because it was traveling through Capricornus, so I was able to kind of track
its progress over the course of many nights. It was really cool, and then over here is where Aquarius
is, very difficult to point out because Aquarius is very faint. I've got a video on that you should
go check it out. Here is another interesting photo of the Moon and Mars, and when the Moon
covers different objects such as planets we call that an occultation. I don't have any videos on
that one, but that will be coming soon. Here we have another picture, and there are two planets in here,
and this one can be a little deceiving because I told you that yes Mars is very bright in the sky,
but there's another planet that is always brighter and that will be Venus. So what we're looking at
here is the Moon, and then this bright star or I'm sorry this bright object is a planet this is Venus
and this right here is Mars. So I wanted to show you this photo so you know the difference between
Venus and Mars. Venus is always brighter. So let's take a look at a couple more pictures here,
okay. Are you able to tell what we're looking at? Okay, you should be able to find the Moon,
you should be able to find Venus, and you should be able to find Mars. So the Moon is obvious. It's
the biggest object in this photograph, but then here is Venus, and here is Mars,
and you can even tell from this picture that Mars has a slightly reddish color to it,
so that's what you want to look for when you're trying to find Mars. This concludes my
video about the Mars 2020 Rover Perseverance. We really have only just started with this mission,
so it'd be really exciting to see the kinds of science and data that comes out of this particular
mission, and it was great to see a successful landing after over a decade of hard work by many
scientists, engineers, technicians, and so on and so forth. They really just did something so amazing
and I'm really really grateful that we get to benefit from their hard work in the future. I
love learning about science, and if you're watching thisI I'm sure you do as well. So let me know in
the comments, were you able to watch the landing? What was the most exciting part for you and
what kinds of things are you looking forward to learning about Mars with this mission? So as always
it takes time patience and practice to study the sky, the stars, the constellations, and of course
the planets. So thank you so much for watching remember to go outside and keep looking up!