nasa just launched its mars rover
perseverance
perched atop an atlas v rocket to lead
one of the most
ambitious and sophisticated mars
missions in history
as the countdown to mars continues the
perseverance of humanity
launching the next generation of robotic
explorers to the red planet
but nasa wasn't alone in the past two
weeks space agencies from
china and the united arab emirates also
launched missions to mars
these spacecraft will travel over 400
million kilometers
before all reaching their destination
around february 2021
but in the past 13 years only seven
rockets sent missions to the red planet
so why are so many attempts to reach
mars all happening
right now space agencies see the red
planet as a key to answering one of
life's biggest questions
are we alone the chemical signatures the
presence of past
water the sedimentation everything about
that planet is
telling us come and look for life here
with cheaper easier access to rockets
and spacecraft technologies
and as more countries develop their
technological prowess
deep space missions are increasing in
numbers not to mention
getting to mars is kind of a flex
becoming part of this
new space race as it were is to show
that you can launch
really ambitious missions that gives you
all the pieces you need to do
much simpler things like put a bunch of
satellites in low earth orbit if you can
get to mars you can kind of do anything
but why are they all going to mars now
well it comes down to planet alignment
payloads and
orbital constraints spacecraft are heavy
but need to travel fast
very very fast and they take a lot of
effort to just get off the ground
so it's important to maximize efficiency
and reduce weight or payload where you
can
faster shorter trajectories or flight
paths that use minimum fuel are critical
for deep space
exploration you can send up heavier
flights for lower costs
but mars and earth orbit the sun at
different distances and speeds
so they aren't always aligned at the
farthest point of their orbits
mars and earth are 401 million
kilometers away from each other
and if you try to go then you're gonna
spend a long time traveling through
space
but at their closest the two planets can
be less than 60 million kilometers apart
every two years the planets in their
orbits kind of get really close together
and that shortens the distance
dramatically by 100 million miles or
more
to getting to the red planet and that's
where we're at in this current launch
window from mid-july to mid-august
waiting for that planetary alignment
gives you a huge advantage in terms of
speed
allows you to send bigger spacecraft
that can do more thanks to the planet's
different orbits this window to launch
lasts for about a month
and it only comes around every 26 months
so if nasa hadn't launched perseverance
by august 15th
it would have had to wait until 2022 to
try again but being close
is only part of the launch strategy when
you send a spacecraft from earth
it doesn't just go straight to mars you
launch your spacecraft you get it sort
of parked
around the earth and it's circling the
earth at thousands of miles an hour
and then at just the right moment you
fire the spacecraft engines
so that it gets on this path to mars and
just sort of coast the rest of the time
that path is known as the homan transfer
orbit
you can see that here an elliptical path
that fluidly connects earth's orbit
around the sun
to other planets orbits in this case the
planet in question is mars
once you fire your engines you're sort
of like coasting down this river
toward mars because the ground the
gravitational pull
of the planets and the the velocity of
your spacecraft is just gonna like
pull you right toward mars the
spacecraft will then meet mars at the
intersection of their orbits about
seven months down the line so timing is
key you can think of this like a
quarterback throwing a football to the
receiver
you're throwing the ball to where the
receiver will be not where the receiver
is currently running
if the timing is wrong by even an hour
and the spacecraft lacks enough fuel to
correct the mistake
then the spacecraft might miss mars
altogether and carry on in the home in
orbit alone
but if the timing is right you get to
mars depending on the mission
you might slip into mars orbit before
attempting to land on the surface
or you might go straight to the surface
if you've got a lander aboard that
spacecraft you deploy it and then begins
what many call the
seven minutes of terror this is the
riskiest part of the mission
the seven minutes between the spacecraft
hitting the martian atmosphere at 19
500 kilometers per hour to softly
landing
so when you're plowing through the
atmosphere to slow down the spacecraft
you're generating all the superheated
plasma ahead of it
that creates a scramble of
electromagnetic radiation
which blocks out your radio signals you
can't talk to your spacecraft it can't
send you data
so you have to wait until it's on the
ground before you can
really know what's happening
communications between earth and mars
take at the very least
10 minutes round trip so the landing
must be perfectly automated but this is
exactly what nasa is aiming to do with
perseverance
which is skipping orbiting mars and
shooting straight for the surface
if the car-sized nuclear-powered rover
safely lands
it will use its 19 highly specialized
cameras
to help create groundbreaking 3d imagery
so it can drill samples
out of the soil and stash them on the
rover for a future mission to come
and collect them and send them back to
earth these would be the first ever
samples
of mars sent to earth for humanity to
look at
a small helicopter is even hitching a
ride on the rover's belly
the copter called ingenuity will be used
to test the first ever controlled flight
on another planet
the goal of all of this is to learn
about mars geology and climate
looking for livable environments and
evidence of ancient microbial life on
mars
yeah you heard that right life on mars
as for the other two missions as we know
perseverance isn't alone on its journey
to mars
one is the united arab emirates hope
probe this
is a satellite that's going to orbit
mars and try to crack some of the
climatological mysteries of the red
planet you know how do the seasons work
how do the gases move around
how do those levels of gases change over
time and then there's china's more
ambitious
tianwen one mission this is a spacecraft
that has an
orbiter a lander and a rover on it and
it's going to try to do basically all
the things you can do on mars
if china succeeds it would become the
third country ever to land on the red
planet
all three missions are major steps in
space exploration and
answering some of humanity's biggest
questions but we'll have to wait until
february to find out if they all arrive
safely
so buckle up and prepare for the ride