aircraft makes some of the best platforms for science here on earth from
weather balloons to study the high atmosphere to aircraft that fly into the
hearts of hurricanes from surveys of Antarctic ice sheets to drones so it
makes sense to consider missions to any world in the solar system with an
atmosphere balloons to Venus and helicopters to Titan the one world
that's been the most seriously considered for exploration by air is
Mars as we've mentioned time and time again in the past Mars sucks especially
its atmosphere you can't breathe it you can't use it to keeping your precious
fluids in ruined spacecraft what's it good for
it turns out it could be possible to fly in the thin atmosphere of Mars an
aircraft's lift depends on the atmospheric density velocity and the
area of the wing since the Martian atmosphere is less dense
you've got to compensate with either a faster speed or a much larger wing area
the one thing in an airplanes favor though is the lower gravity on Mars only
38% of Earth for a faster speed we need more energy but solar radiation on Mars
is much less than what we can enjoy here on earth for bigger wing area you've got
to deal with the limits of landing large complex payloads on Mars which we talked
about in the previous episode needless to say this will be tough but
surprisingly it's possible space agencies have been trying to work out a
way to make it happen for years one of the earliest ideas came from Verner von
Braun the architect of Germany's rocketry program during World War two as
well as the architect for nasa's human exploration of the moon in his mars
project concept he proposed that interplanetary spaceship would be able
to deploy gliders to enter the Martian atmosphere but then it was discovered
that Mars atmosphere was a fraction of the density of Earth's and the idea was
discarded in fact I've done a whole episode on the Mars project so I'll link
to it here once they knew the actual density of Mars atmosphere NASA began to
seriously consider a craft for Mars in the 1970s another
challenge is that Mars doesn't have enough oxygen in its atmosphere to
provide combustion for jet fuel in 1977 NASA's Dryden Research Center proposed a
propeller driven aircraft powered by hydrazine a common rocket fuel
propellant that has its own oxidizer they built a prototype based on their
mini sniffer uncrewed aerial vehicles and did some tests to see if the
technology could work in the 1980s NASA shifted their plans to a totally new
idea instead of having an aircraft that would land on the surface of Mars and
take off again they considered an aircraft that would enter the atmosphere
directly and start flying at hypersonic speeds in 1996 NASA started exploring
the airplane for Mars exploration or aim this would use a propeller and a large
wingspan sail plane in 1998 they refined their idea to build a large folding
glider called Kittyhawk which would unfold at an altitude of 12,000 meters
above the surface of Mars and then glide until it crashed in 2002 nasa's langley
proposed a Mars aircraft called Ares or the aerial regional scale environmental
survey ares would have been sent to mars in an aeroshell similar to the Viking
landers once it got into the thick part of its atmosphere the aircraft would
deploy a parachute unfold its wings and then fire its liquid propulsion engine
it would then be able to fly through the Martian atmosphere for about 500
kilometres sciencing as hard as it could before crashing onto the surface of Mars
all that expense for a few minutes of flight in order to maintain flight and
avoid stalling aircraft need to fly at least 350 km/h on Mars
this means they pass over the landscape too quickly to collect a lot of signs
too fast not enough science next idea was to build an aircraft with a very
large wing that could actually fly around in the thin Martian atmosphere
for longer but not much longer in 2015 scientists flew a test glider concept
called the preliminary research aerodynamic design to land on Mars or
parental em which also happens to be the name of the German engineer ludwig
prandtl who developed a lot of the mathematics for flight see how these
acronyms work the Prandtl M is one big wing with no tail designed to create the
minimum amount of drag and maximize flight time imagine an albatross made of
carbon fiber and aluminum the aircraft would be small enough to fit within a
CubeSat sent to Mars when the spacecraft arrived at Mars and it decelerated
through the atmosphere it would deploy the aircraft it would use its low drag
to glide through the atmosphere for about 10 minutes traversing 32
kilometers of distance before crashing onto the surface of Mars that's not much
but it would be a relatively inexpensive way to scout out a potential landing
ellipse for a future mission sent to a hazardous region of Mars several
versions were tested out but in the end a very different aircraft was chosen to
fly on Mars which we'll get to shortly next idea flapping wings on Mars no I'm
not kidding Mars aircraft could flap their wings like an insect a fancier
name for a flapping wing aircraft is an end to monitor just like insects they
don't generate lift in the same way that a bird's wings work instead insects keep
themselves aloft by forming and then shedding vortices on their wings as part
of a NASA Institute for advanced concepts grant in 2002 researcher
Anthony Klose proposed an intimate with a 1 meter wingspan could generate a
similar lift than an insect on Earth might enjoy the aircraft wouldn't need
to fly quickly it would just need to flap its wings really quickly this would
be incredibly power intensive the course burning through its hydrazine fuel
quickly if it was battery-powered however an intro Moktar could deploy
from a rover flap around to do some scouting and then land again to recharge
its batteries I love this idea and I hope that someone continues to develop
it what about balloons of course NASA's considered balloons
balloons work in the Earth's atmosphere because the gases are less dense than
air fill a balloon with hydrogen helium or hot air and it'll gain altitude as
long as the payload is light enough it's a little more
tricky on Mars of course since its atmosphere is so thin
a Martian balloon mission could be equipped with a tank of helium which
inflates as soon as the spacecraft arrives at Mars then it would jettison
its heavy tanks and float around the Martian atmosphere at a constant
altitude this idea was proposed by Robert Zubrin and colleagues back in
1993 as the Mars aerial platform this discovery class mission would fly at an
altitude of seven kilometres above the surface of Mars for hundreds or even
thousands of days imaging the surface at a greater resolution than had ever been
seen before another idea would be a hot air balloon inflated with locally
sourced Martian carbon dioxide atmosphere the Sun would heat up the gas
trapped inside the balloon giving it lift compared to the surrounding
atmosphere but it would only be able to operate during the day heating up in the
Sun going airborne for a few hours then descending during the Martian night to
rest on the surface this would provide a challenge of snagging its lines each
time it comes down to rest it would only be a matter of time before it got
tangled up on rocky outcrop I've got some good news for you NASA is actually
committed to an actual flying mission to Mars and will actually get to that in a
second but first I'd like to thank Kevin Ross Manning Charles Boles
Dustin Roth DJ Cash Simon Poole and the rest of our 812 patrons for their
generous support if you love what we're doing you want to get in on the action
head over to patreon.com/scishow is developing their plans for the Mars 2020
Rover they wanted to include some kind of flying vehicle with the mission in
2017 NASA Langley developed the concept of the Mars flyer an autonomous winged
drone that would be tucked in beside the rover as a travel to Mars once on the
surface 2020 would use its robotic arm to gently place the aircraft on the
surface from there it would take off vertically and then transition to
horizontal flight once it was going fast enough the aircraft would be
maneuverable enough to explore cliff sides and lavitus autonomously mapping
the surroundings and relaying them back to the rover and then once it ran out of
battery power it returns to the launch pad for
charge in 2018 NASA announced that they would be including a tiny autonomous
vehicle with the Mars 2020 Rover launching in July of that year known as
the Mars helicopter this tiny vehicle is about the size of a softball and weighs
only 1.8 kilograms it has two counter-rotating blades that spin at
3,000 times a minute generating enough lift in the thin Martian atmosphere that
it can actually fly around when the Mars 2020 Rover arrives at the Red Planet it
will be carrying the Mars helicopter on board the rover will search its
surroundings for a good launch site gently place the helicopter on the
ground and then move away to a safe distance the helicopter will charge up
its batteries with onboard solar panels and then begin a series of fully
autonomous test flights going longer and longer distances over the course of 30
days on the first flight for example it will fly to an altitude of three meters
and hover for about 30 seconds because it takes many minutes to communicate
with Mars the helicopter will need to make its own decisions avoiding terrain
and choosing a safe landing site this is just a test to demonstrate if a robotic
helicopter like this makes sense future Mars missions could include one or
several of these flying Scouts which would help them identify important
features on the landscape from above imagine future astronauts exploring the
surface of Mars with a cloud of tiny drones helping them Scout the landscape
awesome getting a vehicle that could fly in the thin atmosphere of Mars is going
to be tough every idea has compromises but if engineers can crack it there's
nothing more effective than getting a bird's-eye view of the landscape ahead I
wouldn't be surprised to see more flying vehicles joining future Landers and
Rovers sent to Mars what do you think let me know your thoughts in the
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