As with any journey into uncharted territory, unforeseen problems will almost definitely
arise. And when they do, you better hope you have the means to solve these problems, because
no one is coming to help you in space. The Apollo missions to the Moon where no exceptions
and did indeed encounter a few issues along the way. A problem no one could have
foreseen however, was moon dust. The moon is covered with an extremely fine powder-like
substance. At first glance, it's harmless. I mean after all, it's just dust. But as the
Apollo astronauts would discover, it wasn't as harmless as it first seemed. Moon dust
is created by micrometeorite impacts which completely pulverize the lunar surface. Because
there's no wind or any other natural elements on the Moon which can gradually erode these
tiny particles and fragments they remain extremely sharp.
This moon dust prevented space suits and other
equipment from working as intended. For example, astronauts had trouble moving their arms during
moonwalks as the joints of the suits became damaged by the moon dust. It's so corrosive
that it even cut through 3 layers of Kevlar-like material on one of the astronaut's boots.
To make matters worse, it's also electrostatic which makes it cling to anything it comes
in contact with. After long moonwalks, the space suits where covered in this black soot
that both looked and smelled like gunpowder. As it was more or less impossible not to bring
the dust back into the lunar module, it caused some pretty significant issues for the astronauts
themselves. It got so bad during the Apollo 12 mission that the astronauts were forced
to keep their helmets on inside the module to prevent as much of it as possible from
getting into their eyes and lungs.
Does life exist beyond the Earth?
I've talked about this many times before and of course the answer is always..
..we don't know.
But that isn't technically true. We can almost certainly
say that life does exist on both the Moon and on Mars. When NASA and other space agencies
send stuff and people to other worlds in the solar system, they go through meticulous stages
of sterilization. But there's a great irony in this sterilization process. Because while
these harshly sterilized environments do indeed get rid of bacteria and other microbial lifeforms
that we do not want to contaminate other celestial bodies with, they also provide the perfect
conditions for bacteria that can survive in space and thus other planets. Essentially,
we're able to remove almost everything, except the things that have the greatest chance of
surviving in space. However, just because they hitch a ride to another world does not
mean we'll see Martians or Moontians anytime soon. It's more than likely that these extremophiles
will eventually die instead evolving into something new. Still it is now, for the first
time in our history, technically wrong to say that the Earth is the only place in the universe
with life.
Ever since the discovery of Saturn people have been fascinated by the planet's rings.
It really makes Saturn stand out from the rest of the planets and makes it easily recognizable.
But since the 1970s, we've discovered that Saturn isn't such a special snowflake after
all. In fact, we now know that all the gas giants in our solar system have these rings.
In order of their discovery, these include Saturn, Uranus, Jupiter, and Neptune. But
aside from Saturn, these ring systems are composed of mostly dust and particles which
makes them extremely faint. But there's actually one more body in the solar system known to
have rings. It's neither a planet, dwarf planet, nor a moon but instead something classified
as a centaur. A centaur is a minor planet that orbits the sun between Jupiter and Neptune
and crosses the orbits of one or more planets. And yeah, they're named after the mythological
beings of the same name. The centaur known as 10199 Chariklo is the largest one to be
discovered so far and it just so happens to also have rings. It's the first of it's kind
and before its discovery, no one thought it was even possible for small bodies like these
to have a ring system.
Personally, I think one of the most amazing things about space is weightlessness. Floating
around without the constant struggle against gravity must be an incredibly alleviating
sensation. But weightlessness causes the human body to behave in ways that make completely
normal things not so normal. For example, you can't burp in space. The reason we burp
is because air enters our stomach while we eat and drink for example. But our stomach
doesn't really like air and other gases so it tries to push it back out. All the food
and liquids stays at the bottom while the unwanted gases are pushed to the top. But it's
only able to do this because of gravity. In the absence of gravity or in microgravity,
all the gas, liquids, and food are unable to separate which makes it difficult to only
push gas back out again. This will cause you to slightly vomit instead of simply burping
and is known as a wet burp. Another annoyance comes with urinating. Our body normally lets
us know that it's time to pee when our bladder is around 1/3 full. But in low-gravity environments
the fluid will just keep bouncing around. Only when the bladder is almost completely
full do the sides begin to stretch and trigger the urge to pee. Even something as basic as
sleep can be quite dangerous and even life threatening if not done correctly. What you
need to make sure of before you go to sleep in space is that you have to have good ventilation around
you. Because if you don't, there's a risk that you'll end up with a bubble of your own
exhaled carbon dioxide. This will result in oxygen starvation and best case,
you'll wake up with a severe headache struggling to breath.
Being an astronaut requires you to be exceptional at a lot of things. One example is that you
need to be able to remain calm and focused during very stressful situations. But that's
of course easier said than done, given that when you're out on a spacewalk there's only
a suit between you and the vacuum of space. Now what if, against all odds, your space
suit began filling with water. In 2013, this is exactly what happened to Italian astronaut
Luca Parmitano while performing repairs on the ISS. Roughly an hour into the spacewalk
he noticed that his helmet was slowly filling with water. As he reported this to the people
on the ground, the volume of the water just kept on increasing and at the time they couldn't
figure out where it was coming from. Eventually it was deemed that there was a chance of him
actually drowning in his own suit so the mission was quickly aborted. It was later revealed
that the liquid cooling system in the suit had caused the leak. Of course Parmitano,
being a trained professional, remained completely calm when faced with the possibility of being
the first man to drown in space.
This is the only photo taken from the surface of another body beyond Mars. It was taken
in 2005 and is from the surface of Saturn's largest moon Titan. Now, Titan is an interesting
place. Just like the Earth it has lakes and rivers. Unlike the Earth, these are
not filled with water but instead liquid ethane, methane, and propane. You see, the average
temperature on Titan is around -180 °C. Because it's so extremely cold, the probe only remained
functional for about 90 minutes after touchdown and was only able to send this single photograph
from the surface. Titan also has a very interesting atmosphere which consist of a thick haze.
The atmosphere is several times denser than here on Earth and gravity on Titan is several
times weaker. If you weighed, say 80 kilo, you would only weigh around 12 kilo on Titan.
In fact, if you could theoretically survive on the surface and had a wing suite on. Because
of the low gravity coupled with the dense atmosphere, you would be able to fly simply
by waving your arms around.
In 1936, just before the eruption of World War II, Adolf Hitler made a speech during
the Olympic Games Opening Ceremony which was broadcasted to 41 countries across the globe
reaching millions of people. It's significant because it was broadcasted at a very high
frequency which likely allowed the signals to get through the Earth's ionosphere. In
other words, the signals where able to escape the Earth and continued out into space. This
has lead some to believe that one of the first things potential aliens might hear are the
words of Adolf Hitler. In fact this is the exact plot for the book written by Carl Sagan
titled Contact. It was even made into a movie in 1997. But this is only within the realm
of science fiction and could never actually happen in real life. You see, many TV-shows
and other signals like these will drastically diffuse over time and at best will only be
able to propagate a couple of light years away before they become identical to background
noise. It's something known as inverse-square law. Even if some of these signals inexplicably
made it to some of the closest exoplanets to the Earth. And we assume that intelligent
extraterrestrials do exist on one of these planets. And these aliens just happens to
aim the correct technology able to pick up these unbelievably weak and quiet signals,
towards the Earth. They would still most likely not be able to extract any audio, visuals, or other tangible
information from these signals. They would simply be too feeble and diluted once they get there.
However, given that they can detect these signals in the first place,
they would likely recognize them as a technological signatures. Something that could not have
occurred naturally in space and would thus give them a confirmation to the eternal question;
"Are we alone in the universe?".
When we think of planets, we think of them as orbiting around a star. In fact a planet
is defined as: "A celestial body moving in an elliptical orbit round a star." But what
if something should happen to that star which leaves the planet all alone. Or if something
happens to the planet which causes it to slingshot away from its star system on an endless lonesome
journey through the cosmos. Astronomers have theorized about the existence of such rogue
planets for decades and its only recently that we actually found them. But they can
be incredibly difficult to discover. After all once they leave their parent star, they
becomes near invisible against the blackness of space. The planet will find itself in an
eternal state of night and the only visible light would come from the galaxy itself. Some
estimate that there could be billions of rogue planets in the Milky Way alone, but so far
we've only found a handful. Most of which could just as well be brown dwarfs, or in
other words a failed star. But the concept of a rogue planet gives rise to a whole set
of new questions. One of the most perplexing; could life potentially exist and survive on
a planet without a star?
Maybe. If it's a planet with a lot of water, that water will
obviously freeze as it's exposed to the near absolute zero temperatures of space. But ice
is actually a pretty good insulator. So if the ocean is at least a few tens of kilometers
deep, the water will remain liquid at the bottom because of the heat internally generated
by the planets core. Life could then thrive around hot spots, like hydrothermal vents
on the ocean floor. Another alternative would be if the planet had an extremely hydrogen
rich atmosphere. It would need to be tens or even hundreds of times thicker than the
atmosphere here on Earth which would then act as an insulator to retain liquid water
even at the surface.
Orbital debris, which is any man-made object in orbit around our planet which doesn't serve
any useful purpose, is becoming an increasing problem. We're currently tracking around 600,000
pieces of debris larger than 1 centimeter. Roughly 30,000 of these are over 1 decimeter
wide. But there's still many hundreds of millions of pieces which are simply too small to keep
track of. What's so dangerous about these seemingly insignificant tiny fragments is
the speed at which they travel. They orbit the Earth at speeds up to 28,000 km/h. Even
something as tiny as flecks of paint can be disastrous when traveling at these velocities.
In fact a number of space shuttle windows have been replaced simply because of damage
caused by flecks of paint. Usually, when a tracked piece of debris is about to collide
with a functional spacecraft, a so called "debris avoidance maneuver" is performed.
This actually happens all the time and even aboard the ISS in which the entire space station
is moved a few kilometers to avoid a potential collision. But the thing is we may already have crossed
a point of no return. Even if we stop sending anything into space right this moment it will
continue to get worse. You see, the amount of debris which is already in orbit will continue
to collide with each other and thus create even more debris. So far the problem is manageable
but a solution needs to be found quickly. And while NASA and many others are working
on solutions, it's not an easy problem to solve. I mean, the shear scale and cost of
resolving this issue is like nothing we've ever seen before and if we do nothing we will
quite literally enclose the Earth in a blanket of garbage.
There's something known as the "overview effect". Many astronauts and cosmonauts alike have
reported a strong sensation of euphoria and even a significant cognitive shift in their
perspective on life as well as themselves once they saw the Earth from a distance. Many
have explained it as an overwhelming sensation that everything in the universe is somehow
connected, that national boundaries completely vanish, coupled with the realization that
our world is incredibly fragile. It sounds like they're high, right? Maybe someone brought
a little something with them on their trip to space, who knows. But at the same time
it seems like a quite reasonable reaction. Looking back at the Earth from a distance
must be an experience like none other.
And what makes it so interesting is that it's
not an isolated incident. Many people who have returned from space after looking back
at our planet, either from orbit or from the Moon, have explained the sensation in a very
similar fashion. Psychologists, neuroscientists, and physicians have all reported that many
of these people have had a notable shift in their behavior and outlook on life and the world.
To end this video, here's a quote from astronaut Edgar D. Mitchell describing what
he experienced upon seeing the Earth from the Moon.
"You develop an instant global consciousness, a people orientation,
an intense dissatisfaction with the state of the world,
and a compulsion to do something about it. From out there on the moon,
international politics look so petty.
You want to grab a politician by the scruff of the neck
and drag him a quarter of a million miles out and say:
'Look at that, you son of a bitch'."
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