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yep we all know what the Sun is why
summer is hotter than winter and that
vacuum is absolutely empty but do we
really it turns out lots of things we
think are common knowledge at this point
are in reality not so obvious the Sun is
a fireball the keine what we see as the
Sun in the skies is the result of
innumerable processes of nuclear fusion
this releases an unimaginable amount of
energy every second but nothing here is
actually burning for fire to burn it
needs oxygen and it's really scarce in
the Sun the Sun is yellow the power in
our sun's light is so immense
we just can't put a stamp of one color
on it it's a lot of colors mixed
together which makes it appear as white
we see the Sun as yellow or orange
sometimes red only because the
atmosphere of the earth scatters colors
like blue green and violet this is also
why we see the sky as blue water is
extremely rare in the universe both of
the elements water consists of are among
the most abundant stuff in the universe
we think water is scarce only because we
rarely found it on our neighboring
planets but science proposes there are
lots of huge worlds having up to half of
their mass as water to compare our
planets mass is only 0.02 percent water
all comets have tails
in reality comets are almost invisible
before they get close to the star and
their tails appear this tail consists of
ice scattering away when the comet gets
closer to the heat of the star if the
comet isn't heated it won't have a tail
the void of space is cold space isn't
just cold it's extremely cold - 454
degrees Fahrenheit nothing a sweater can
save you from but relatively close to
the Sun it gets up to 250 degrees this
is also why space suits are white they
need to reflect as much light and heat
as possible orbits are circles with
massive space objects in their center
well the Sun holds planets in their
orbits
due to its gravitational pull planets
have their own pull that shifts the
center of orbit away from the Sun it
looks more like they dance with each
other
Plus orbits have elliptical shapes not
circles summer is warmer because we're
closer to the Sun nope not at all
during summer the Sun is above the
horizon for up to 17 hours a day but
during the winter it's just six hours
this happens because the axis of the
earth is tilted at an angle so at one
time of the year the northern part of
the earth catches more sunlight and at
another time it's the southern parts
turn to get more warmth astronauts work
out on orbit because they need muscular
bodies to work in space the gravity on
orbit doesn't affect your body and it
doesn't work as much astronauts work out
because they need to be ready to return
back to earth and it's gravity without
feeling like they're about to get
squished it's difficult to go through
asteroid belts well unlike the movies
real asteroid belts are kind of boring
and empty between two space rocks in a
belt lie huge distances of nothing at
all going through one in a spaceship
with decent planning would be a walk in
a park except here in space
sound and fire in space there's no
oxygen in space so if a spaceship goes
boom any fire will burn out the oxygen
inside the ship and then just fade and
in the vacuum of space there's not
enough matter to transfer the sound the
Sun would be definitely loud otherwise
since it basically produces innumerable
colossal blasts happening every moment
light years our units of time if you
like sci-fi stories or read science
articles you know this for sure but some
people still don't realize a Lightyear
is not time but the distance one photon
can go through the vacuum of space in a
year light is always the fastest thing
ever
kinda but only in a vacuum
today we know several ways to slow down
photons it will move slower through
different substances electrons on the
other hand will move at the same speed
in these substances and sometimes they
will be even faster than light the
vacuum of space is absolutely empty well
despite having little or no matter in it
the vacuum is actually filled with
energy fields interacting with each
other they can even produce particles
gas giants are made of gas seems obvious
I mean planets like Jupiter or Saturn
are called gas giants but they still
have solid cores deep inside them in
theory at least because it's impossible
to study gas giants properly any probe
would get smashed by immense pressure as
soon as it gets too close super-earth
planets are like the earth but bigger
this term only describes the size these
planets are bigger than the earth but
not as big as let's say Uranus or Saturn
black hole swallow everything around
them like colossal funnels black holes
got their name because we can't see them
directly these are objects so massive
and dense their force of gravity works
as a trap even light can't escape it
other objects can orbit them like
planets orbit the Sun still if you get
past the event horizon of a black hole
mm-hmm there's no turning back the solar
system has eight planets
there's mathematical evidence that this
might be wrong but much farther from
outer reaches there should be a planet
ten times more massive than Earth no
names yet scientists still has to
confirm its existence we know how big
the universe is the furthest place from
where light ever reached us was 13.8
billion light years away from the earth
but the universe is constantly expanding
extremely fast and if something was 13.8
billion light years away from us by now
it's even farther away mercury is the
hottest planet in the solar system
mercury is closest to the Sun but Venus
is much hotter mercury has no atmosphere
while Venus has one it mostly consists
of co2 that traps heat inside and adds
to the high temperature the open space
has a smell sometimes astronauts say
that it smells like a Burt steak but
what they actually mean by that is when
they come back to the space station from
a space walk or something and take off
their helmets they sense this smell from
their spacesuits it's impossible to
smell the vacuum of space itself we can
see a million stars in the skies
well the number is actually much more
modest only about three thousand stars
there are lots of other objects we may
also see and mistake them for stars
planets in the solar system distant
galaxies and just satellites everything
in the solar system is locked in its
place nope everything is always in
motion the moon becomes more and more
distant from the earth with each year
and we're also going away from the sign
the speed of such shifts and movements
is too small to be a big deal for us but
it happens constantly moon's orbit
planets in the same direction planets
rotate well Triton is the biggest moon
of Neptune and it's the only one in the
solar system that goes in the opposite
direction it also gets closer to Neptune
with each year and one day it'll get
smashed by it and become another
asteroid ring we're on the verge of
interstellar travel we have literally no
technology that would allow that in our
lifetime and probably ever nothing can
go faster than life and for big objects
it's virtually impossible to reach even
a fraction of such speed that means that
going interstellar would take ages upon
ages to do and people have no idea how
to get around this problem but
interstellar travel does make for
exciting movies and it prevents space
movies from being 50 years long which
would make the classic phrase are we
there yet even more annoying hey if you
learn something new today then give the
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bright side of life
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