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when it comes to Saturn it's hard to
summarize just how lucky we were to have
the Cassini hyan
Mission four robotic probes have visited
sattin but of those Cassini hyans has
hands down been the most impactful and I
mean that both literally and
scientifically its data has provided the
Bedrock for over 4,000 research papers
it discovered six new moons and helped
better understand their composition it
survived 20 years traveling 7 billion
kilom and spent 13 of those years around
Saturn itself Gathering data on Saturn's
gravity magnetosphere its rings and its
structure and Cassini kept Gathering
data right up until the last moment of
its life as it plunged into the mustard
clouds of Saturn's atmosphere and
ultimately broke into thousands of
people
pieces couple that with the fact that it
provided some of the most jaw-dropping
or inspiring images of Saturn and the
solar system to date and you have one
hell of a
mission I'm Alex molan and you're
watching Asam join with me today for
this Cassini super cut as we explore its
Grand Finale the period of time before
the dive what it discovered before and
during its plunge and the incredible
discoveries continuing to be made to
this day from the clues that Cassini
hyans provided
us if you want to see Saturn's Beauty
there is no better way to do it than
Through The Eyes of Cassini in its Grand
Finale the first probe to reach Saturn
was the Pioneer 11 probe in
1979 it was at this time that scientists
confirmed that Saturn's largest moon
Titan had an atmosphere
spere they knew they had to go back and
visit the moon but this time with a
Lander Now Voyager 1 and two were
already on route to Saturn at that point
so naturally it was too late to include
Alanda with those missions thus Cassini
hyans was born and in October 1997 it
was launched into
space getting a spacecraft to Saturn is
no mean feat as the whole trip was
combating the gravity of the sun trying
to pull Cassini back to the inner solar
system so to help achieve the speed
needed to reach Saturn Cassini used
planets as gravitational assists it flew
by Venus twice before returning back to
Earth Earth's gravity then slingshotted
it towards Jupiter which gave it the
final push needed to reach Saturn this
alignment of planets which allowed these
gravity assists only occurs once every
600 years so timing in this case was
crucial and Cassini really scraped past
Earth from the second time around too it
was only 1,100 kilm above Earth's
surface at its closest
approach this is made even more
interesting when you realize what
actually powered Cassini it was by three
rtgs or radioisotope thermoelectric
generators basically the power source
came from about 33 kg of radioactive
plutonium
it's this radioactive decay which gave
Cassini power and even until the end of
its life it still produced about 700
Watts the issue with the spacecraft
carrying this radioactive substance was
that if scientists had gotten their
calculations wrong and a crash landed on
Earth everybody on the planet would have
been exposed to the
radiation now 33 kg spread out over the
whole earth is a very small amount but
in the worst case scenario NASA
estimated it would have caused about
5,000 deaths from
cancer they put this down as an
acceptable risk though as the chances of
this happening were only one in a
million Cassini used RGS because solar
panel technology wasn't good enough at
the time for the sun to power something
so distant with rtgs Cassini would have
a very long operational life and it
might still be able to carry on even now
if it wasn't for the fact it eventually
ran out of propellant
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fuel Cassini had numerous objectives to
understand the structure and dynamic
behavior of Saturn's rings explore
Saturn's moons more fully measure the
magnetosphere of Saturn study Saturn's
atmosphere and study Titan more
extensively this last part is where the
hyans part of Cassini hyans comes into
play you see hyans was a Lander attached
to the Cassini spacecraft designed to
see what was going on under the hazy
clouds of
Titan hyans is the part of the mission
built and operated by Isa the European
Space Agency the probe was only about
1.3 M wide and weighed 300 kg when it
detached from the Orbiter it spent 22
days in space before entering Titan's
atmosphere the only system aboard that
was active at this point was a wakeup
timer due to wake up the probe only 15
minutes before it entered the
atmosphere and when it woke up what it
saw was
amazing this video is an actual Spar up
version of the 2 and 1 half hour
descent the main mission of Hans was
actually about this descent taking
readings from the atmospheric pressure
its composition wind speed and so on and
because the mission was only to measure
atmospheric readings the battery life
wasn't expected to last long Beyond The
Landing the scientists thought they
could be landing on an ocean or lake and
so had designed hyans
accordingly from what you see though it
actually landed on what could be the bed
of a dried up
Lake the mission for Cassini itself has
been remarkably successful as well as
scientific data it has picked up over
the course of those last 13 years is it
has been able to provide some of the
most stunning pictures found of space I
just want to showcase some of my
favorites of Saturn and of course
Saturn's moons are beautiful in their
own right too and some very dedicated
Souls have even taken 1 million photos
Cassini has taken to show us what it
would be like to be sitting on the
Cassini
spacecraft these are real images they've
only been color corrected and enhanced
and put in order to show movement
there's no CGI it's simply
amazing as cassini's fuel began to run
low scientists began to consider how
best to get the most data they could out
of the time they had left to achieve
this they sent commands to Cassini
telling it to perform some very close
flybys of the planet and some of its
moons getting closer to Saturn and his
rings than it ever had
before beginning on November 30th 2016
Cassini repeatedly climbed high above
Saturn's North Pole then plunged to a
point just outside the narrow F ring
which is the edge of the main Rings
completing 20 orbits in total then on
the 22nd of April
2017 Cassini would leap over the Rings
to begin its final series of Daring
Dives between the planet and the inner
edge of the Rings this was the Cassini
Grand Finale a series of loops and Dives
that brought the probe closer and closer
to its object of study facing greater
and greater danger as it flew until
finally as its data became purest as
Cassini would fly into the Embrace of
Saturn itself cassini's chance for
annihilation would become
certain NASA's website States the reason
for this final mission as it plunges
past Saturn during the grand finale
Cassini will collect some incredibly
rich and valuable information that the
mission's original planers might never
have imagined the spacecraft will make
detailed maps of Saturn's gravity and
magnetic fields revealing how the planet
is arranged on the inside and possibly
helping to solve the ome mystery of how
fast the interior is rotating it will
vastly improve our knowledge of how much
material is in the Rings bringing us
closer to understanding their Origins
cassini's particle detectors will sound
example icy ring particles being
funneled into the atmosphere by Saturn's
magnetic field and its cameras will take
amazing Ultra close images of Saturn's
rings and clouds No Other Mission has
explored this unique region so close to
the planet what we will learn from these
activities will help improve our
understanding of how giant planets and
families of planets everywhere form and
evolve at the end of its final orbit as
it would fall into Saturn's at
atmosphere Cassini would complete its
20year Mission by ensuring the
biologically interesting worlds
Enceladus and Titan would never be
contaminated by Hardy microbes that may
have stowed away and survived the
journey intact it's inspiring
adventurous and romantic and a fitting
end to this thrilling story of Discovery
but let's take a closer look at some of
these final
moments during cassini's Grand Finale
NASA became willing to trade cassini's
prospects for longevity for a chance at
unprecedented levels of closeness to
Saturn this was an easy trade to make
after all Cassini was running out of
fuel so its survival was already off the
table making this decision meant Cassini
was given the go-ahead to approach the
planet closer than ever before darting
in between the Rings but what did it see
did this unique perspective show
anything we've never seen before let's
take a look at some of the awesome sites
Cassini saw during its Grand
Finale well starting with the moons of
Saturn it has seen some of the shepherd
moons in unprecedented
detail this is a close approach of Atlas
a 40 km wide Moon near the outskirts of
the a-ring what looks remarkable about
this moon is the lack of impact craters
on its apparently smooth surface making
it look absolutely bizarre
dust from the Rings is collecting over
the surface particularly around the
equator of the Moon smoothing it over
and giving it this dis shape a similar
thing happens with the second innermost
Moon of Saturn pan at 30 km wide and
found in the enka Gap any particles from
the rings that stray into the 350 km
wide path get swept up by pan this keeps
the Anor Gap steady and
constant d this is another Shepherd Moon
sadly not seen in quite so much detail
but due to the Gap it is located in its
effects can be seen for hundreds of
kilometers it is only 8 km in diameter
and is found in a very narrow Gap in the
a-ring called the Kila Gap its gravity
is very weak but it is just enough to
whisk the nearby dust particles as it
brushes by this creates these waves or a
ripple effect in the nearby rings
sometimes even ripping material directly
out of the ring visible in this little
Trail
here not only do these ripples move side
to side but up and down too as can be
seen by the Shadows they create I can
only imagine what it would be like to
sit on dness and watch as waves follow
its orbital path with glorious Saturn
and his many moons in the background it
would be quite the sight to
behold talking of the Rings that
Cassini has been able to capture some
spectacular images one of my favorites
from the grand finale is this one
showcasing the Janice 21 spiral density
wave amazingly what you're looking at
here is the result of the same process
that creates spiral galaxies just much
more tightly wound what appears to be
many separate Rings is actually only two
spiral arms looping around the planet
many times so every second line you see
in the image belongs to the same spiral
arm this image is part of the B ring at
a position where the ring orbits twice
for every one orbit of Saturn's moon
Janice causing an orbital
resonance this photo gives the illusion
that the image is tilted away at the top
left but this isn't the case the
illusion is created by the way density
waves propagate from the planet the
wavelength decreasing with the distance
from the resonance and this is where the
resonance gets even more
mind-blowing Janice the Moon that
contributes to the resonance switches
positions every four years with its
close neighbor Moon
Epimetheus every time this switch takes
place the Rings respond creating a new
Crest in the waves NASA says the
distance between any pair of crests
corresponds to four years worth of the
wave propagating Downstream from the
resonance which means the wave seen here
encodes many decades worth of the
orbital history of Janice and
Epimetheus according to this
interpretation the part of the wave at
the very upper left of this image
corresponds to the positions of Janice
and Epimetheus around the time of The
Voyage of flybys in 1980 and 1981 which
is the time at which Janus and epeus
were first proven to be two distinct
objects this encoding reminds me a bit
of a tree trunk encoding how many years
it's been alive by the amount of rings
it has simply
amazing apart from other beautiful and
detailed images of the Rings other
interesting sightings have been these
little propeller features dotted around
the Rings in a number of locations this
image shows both sides of the Rings the
top image shows the illuminated side and
the bottom the unlit side scientists do
this to compare and try to figure out
details even though the scale of the
image is only about 500 m per pixel the
moonlet might not even be able to be
resolved you might just be able to see
some trace of it in this top image but
what can be seen is that the moonlet is
physically connected to the Rings by
this band of
materials as I mentioned this wasn't the
only moonlet trying to create a gap in
the Rings here is another found right
next to the Anchor Gap and here is
another and probably the biggest out of
all three
none of these moonlets are thought to be
bigger than 2 km and probably have the
density of a
snowball the last interesting thing
Cassini was able to image within the
Rings is extremely small but solid
objects which have formed around the
eering potentially caused by the
perturbations of some of the shepherd
moons around
there they seem to be solid as they have
survived crashing into the eing a number
of times kicking out dust and particles
which sometimes then even follow their
orbit as can be seen by the haze around
them the objects themselves are not
actually visible due to the dust
obscuring the
view lastly let's look at the planet
itself as Saturn's Northern Hemisphere
was in full summer at the time Cassini
flew by its remarkable hexagon around
the pole was in full view in the center
of the hexagon is found a permanent
polar vortex with the eyew wall of a
massive
hurricane interestingly the pole seems
to be changing color with the season as
you can see quite clearly in comparison
to 2012 where the pole appeared quite
dark in color with the assistance of
other wavelengths of light other storms
are visible and could be seen dotted all
over the planet as well as bands
reminiscent of Jupiter just not quite so
vivid in natural
light also because of the proximity of
Cassini to the planet it was able to get
a good look at the planet's Horizon on
the left of the image can be seen a haze
in the stratosphere of the atmosphere
that disappears towards the right of the
image when Cassini did enter the
atmosphere on its Final Approach it was
thought it would not survive to even
reach this
Haze however scientists weren't too
worried about that what was of
particular interest to scientists is
what the atmosphere consists of Cassini
would dive into that atmosphere to find
that information and would burn up in
the process making it the last readings
that Cassini would ever
send but one week before it entered the
atmosphere Cassini was still taking
images some of these final images are
fantastic although be aware that Cassini
is not capable of real-time video
capture the videos I'm about to show you
are time lapses the splicing together of
countless individual images into
glorious visualizations of what it would
be like to fly with Cassini on his
ultimate journey into Saturn not all of
these images are of Saturn
itself the first time lapse we will look
at is from the 8th of September 2017
only one week before the end of
cassini's mission one of the main
focuses of Cassini during its mission
was the moon Enceladus one of the Prime
candidates in the solar system to
contain life in a subsurface
ocean Cassini discovered over 100 water
plumes erupting through the moon's crust
from this ocean water which freezes in
the space environment and has now formed
the beautiful e-ring around Saturn this
ring is very tenuous only visible when
back lit by the Sun and is potentially
The Bluest naturally occurring object in
the solar
system here is a great view of
enceladus's effect on the densest part
of the earring you can see the plumes
disturbing and replenishing the
ring cassini's final look at enceladus's
plumes were captured in this remarkable
time lapse taken over a 14-hour
period on the 11th of September Cassini
was near the furthest point of its final
orbit and captured this beautiful Mosaic
in natural
light visible are the thickest of
Saturn's rings D C B A and F with
Saturn's short Shadow being cast over
them Saturn's Norther Northern
Hemisphere was experiencing summer
during this time which means that
Saturn's most famous hexagon storm is
visible in all its Glory you can also
just about notice Saturn's subtle bands
in natural
light what's really interesting about
this image however is that the night
side of Saturn is dimly illuminated this
is due to light reflecting off the Rings
meaning Saturn's kns in the hemisphere
facing the sun don't get that dark below
the glow of the Rings Saturn is pitch
black as Cassini began to approach
Saturn again on the 12th of September he
took images of Saturn's atmosphere near
the planet's Terminator line incredibly
because the sun is so low in the sky
here huge Cloud structures can be seen
casting Shadows that stretch for many
kilometers you may think this is a
closeup of Saturn but actually we are
looking at the scene about 5,500 km
across Saturn's moon Titan could easily
fit in the
shot Cassini was getting closer and
closer to Saturn on the 13th of
September it appeared one last time at
dfes and some of you Keen observers will
notice ripples in front of the Moon as
well as behind this is due to orbital
speeds of the Rings and the moon the
inner ring orbits faster than dness
meaning the ripples overtake the moon
exposing more ring material to the
moon's gravity on the other hand the OU
to ring travels slower than dness
meaning the ripples lag behind the Moon
by the time the ring material reaches
dness on either side again the ripples
have already smoothed
out on the same day Cassini had one last
look around the satin system it captured
a view of Titan a moon it focused on
heavily during its Mission a remarkable
world with a thick nitrogen
atmosphere it also appeared at Saturn's
rings with the uneven F ring just about
visible at the bottom of the image and
as Saturn got bigger it took one last
look at Enceladus over a 40-minute
period before it disappeared from view
behind the limb of
Saturn the final image Cassini ever took
was looking over the region where it
would plunge into the atmosphere it was
night time here and so Saturn is lit up
by light reflected off the
rings on the final day photos were not
on the sci's agenda
as beautiful as they are they use up a
lot of valuable bandwidth and scientists
wanted to get every bit of data real
time before the spacecraft was destroyed
this was a unique opportunity we had
never probed Saturn before
this when Cassini first hit the tenuous
parts of Saturn's atmosphere it was
traveling
123,000
kmph the remnants of cassini's fuel were
deployed by its thrusters to keep
cassini's antenna aimed at Earth at this
point Cassini was 1,900 km above
Saturn's
clouds a minute later these thrusters
were firing at maximum capacity to keep
Cassini from spinning out of control
Cassini was directly sampling Saturn's
atmosphere but this atmosphere was also
heating Cassini
up just 10 seconds later the thrusters
were overcome and Cassini began to
Tumble cutting off communication with
Earth cassini's onboard computers at
this point would have been trying to
figure out what was going wrong
gyroscopes and star trackers would tell
the computer that it is spinning and it
would likely have gone into a safe mode
to divert power in an attempt to write
itself a minute or so later the
spacecraft would have disintegrated all
together and burned up in Saturn's
atmosphere as data started arriving one
and a half hours later on Earth this
final part of the mission was deemed to
be a great success Cassini recorded data
from direct analysis of Saturn's
atmosphere its ionosphere dust particles
in the atmosphere and from magnetic
field measurements and perhaps more that
has yet to be uncovered from the data
and that's the amazing thing about the
Cassini Mission it just keeps on giving
science papers and discoveries are still
being made as the data it collects is
analyzed and
re-examined what have we discovered from
cassini's data in the years since his
ground breaking Mission you're about to
find out but be aware some of the things
Cassini has learned about Saturn has
only serve to make the planet even
stranger you may think you know Saturn
it's iconic rings are the largest in the
solar system and its hazy yellow surface
is both enigmatic and instantly
recognizable it is the second largest
planet the least dense and the sixth
from the Sun
and yet Saturn is an enigma there is a
vast mystery lurking beneath its
obscuring atmosphere uncovered by the
Cassini probe one that the scientific
Community still does not have consensus
about Saturn behaves in ways that our
conventional models claim is impossible
from its temperature to its
magnetosphere to even the very length of
its
days what is going on with Saturn and
what are our best attempts at explaining
these baffling
phenomena the Cassini probe arrived at
the gas giant on the first of July 2004
it was not the first probe to arrive at
Saturn three others had already done
flybys however it was the most
thorough as we have already mentioned it
spent 13 years circling the planet
collecting reams of data using its
various spectrometers magnetometers and
other equipment the knowledge it gave us
has been a huge benefit but sometimes
only serves to deepen Saturn's
Mysteries take for example that hexagon
storm on Saturn's North Pole the edges
of this 29,000 km wide storm could each
fit the Earth comfortably inside and as
best as we are able to tell does not
shift its longitude remaining fixed at
its location traveling with the rotation
of the planet unlike the rest of
Saturn's swirling clouds pushed Along by
its up to 1,800 kmh
winds the storm is undeniably a strange
one scientists do not yet have a full
explanation for it although there are
some lab experiments that have created
close approximations to hexagons on much
smaller scales but it is not
alone as the mountains of Cassini data
started getting analyzed in the years
since the end of its Mission more
Mysteries have started coming in it
started with a fairly innocuous question
how long is a day on
Saturn although we've watched Saturn in
our sky for thousands of years
scientists did not yet have a definitive
answer after all it wasn't as simple as
looking up at the planet and seeing how
long it took for its Rocky core to
rotate Saturn's thick cloud cover
obscures any landmar marks that might
exist on any hard surface below and
those clouds move at different speeds to
the core due to the powerful
wind the Rings themselves orbit Saturn
at different speeds so they don't settle
this question you can't look at how fast
they orbit and hope it's the same after
all most moons don't do this so rings
are no
different rather cleverly scientists do
have techniques for figuring out the
rotation of a gas giant by looking at
its magnetic field and it was hoped that
this method might be used on Saturn
planets with magnetic fields produce
them via a Dynamo effect as the planet
rotates liquid metal in the core spins
and shifts and this colossal motion of
molecules creates massive currents of
energy which in turn produce magnetic
fields one feature of this is that
thanks to this rotation the pole of this
magnetic field is always off from the
axis of rotation for the planet itself
if the two lined up the magnetic field
wouldn't survive for long so all you
have to do is detect the magnetic fields
around a planet which Cassini could do
and watch as the magnetic pole shifts in
a circle around the true axis of the
planet once the magnetic pole has
completed one rotation you have your
day only Saturn apparently does not play
by the rules and its magnetic pole is
almost perfectly aligned with its axis
of rotation to an order of accuracy of
less than 0.1 de and in spite of dynamo
theory claiming that this should be
impossible Saturn's magnetic field is
Alive and Well its Magnetic Moment is
580 times more powerful than Earth and
is extremely influential on the Saturn
system as a whole scientists do not know
how this magnetic field occurs as it is
impossible under dynamo theory but no
other method for producing such a field
is proven either a planetary Dynamo is
at play in Saturn's core but some other
effect is occurring in the atmosphere to
warp the magnetic field lines to be
perfectly aligned with the axis of
rotation or we are observing a
completely new method of producing a
magnetic field on
Saturn so it was back to the drawing
board for solving a satin day
fortunately radiation proved to be of
more
help Saturn is an electrically live
system charged ions move between the
layers in its atmosphere even between
its rings and its ionosphere scientists
noticed that Saturn emitted radio waves
as a result of all the magnetic fields
at play and these radio waves Rose and
fell in
intensity in fact it seemed to mirror
what you might expect to see as a result
of the planet rotating higher levels of
radiation would appear every 11 hours or
so as a result scientists concluded with
some certainty that this was Saturn's
day length their initial estimate based
on Voyager data was 10 hours 39 minutes
and 23 seconds it was hoped that Cassini
would be able to improve the accuracy of
this
figure initially Cassini was able to do
so but then it got really weird because
over the course of the 13 years of
cassini's study of Saturn
this number started to shift it drifted
about 1% over the course of a year
sometimes Rising sometimes falling this
almost seemed to imply that the planet
itself was altering the speed of its
rotation sometimes speeding up and
sometimes slowing down to be clear a
planet as massive as Saturn should not
be doing that as such scientists
concluded that this wasn't happening and
some effect must be once again muddying
the waters around Saturn some aspect of
the atmosphere was causing shifts in the
fields making the radiation fluctuate
over time hiding the true rotation of
the planet beneath a cloaking
Shimmer another key consequence of the
planet's magnetic field is the auroras
that shine at Saturn's
poles but while on Earth our auroras are
the result of solar wind interacting
with our atmosphere it is thought that
this does not account for the auroras on
Saturn Cassini detected that at least
some of them occurred regardless of what
the solar wind was doing at the time
meaning that Saturn's auroras are nons
solar
originating something strange must be
going on inside Saturn it was hotter
than it ought to be too it radiates out
into space about twice as much as it
receives from the Sun and while some of
this may just be gravitational
compression of the Planet the rest
needed some other way to account for It
ultimately all of this needed some
unifying explanation and fascinatingly
thanks to cassini's data we discovered
the key to all of it may lie within
Saturn's gaseous
atmosphere Saturn is a gas giant it is
almost entirely made of hydrogen and
helium not all of this is gas as the
great mass of sattin means that the
deeper into its atmosphere you go the
more intense the heat and pressure that
you are subjected to it is thought that
this pressure forces gaseous hydrogen to
become liquid
metal some scientists theorize that this
liquid hydrogen or perhaps even hydrogen
compressed so densely that it becomes
Diamond rains down into the depths of
Saturn and the friction this generates
explains some of Saturn's unusual heat
but the the rest comes from the auroras
although these are not fully understood
it is thought that they are the product
of electrically charged particles coming
into Saturn from its rings and moons
whatever their Source these auroras may
be creating enough heat to warm the
upper atmosphere of the
planet temperatures so hot create other
effects where warm fronts meet cold
powerful winds are formed it is
theorized that these winds carry charged
ions around Saturn's upper atmosphere
and these electrically charged winds are
what is skewing the data from Saturn's
radiation causing its variance perhaps
such motion of electrical currents might
also explain why Saturn's magnetic
fields are not where they are supposed
to be this could be caused by a
conductive layer within Saturn's clouds
moving at a different speed to the
others creating fields of their own at
least so goes the explanation
in all this it should be clear that many
of these answers lack final proof
scientists are trolling through the data
given by Cassini hoping for further
insights if these are not forthcoming
then ultimately it will take another
mission to Saturn to find the answers to
these puzzling
questions but what about the length of
Saturn's day thankfully this one mystery
does have an answer and it turned out
the clue lay in the Rings after all
rather than investigate the electrical
and magnetic effect of Saturn on its
rings scientists realized that Saturn
would also Target them through its
gravity this is fairly obvious but what
was more insightful was that Saturn
would not Target them uniformly Saturn
is not a perfectly round ball any
variance in its shape result in variance
in its gravitational field Saturn's
rings were a perfect canvas to look out
for such variants as Saturn pulled at
its rings with a rising and falling
Force at certain locations in the Rings
it would be able to detect
ripples scientists started looking for
these Ripples and located them by
measuring the distance between them it
was finally possible to calculate the
length of Saturn's day they weren't far
off it was 10 hours 33 minutes and 38
seconds and this this time scientists
are fairly certain that they've got it
right so at least this mystery was
solved and yet Saturn's other Mysteries
still persist the next mission to Saturn
will launch in 2027 with NASA's
dragonfly although this will focus more
on exploring Titan Saturn's largest moon
Titan is the most earthlike object in
the solar system as it is the only place
thought to have atmosphere filled with
nitrogen similar to ours albe it with no
oxygen and Rain cycles and liquid legs
on its surface although these are
methane rather than water so it's
understandable why scientists want to
give it a look still it means that it
may be some time before Saturn's deepest
Mysteries find themselves
answered Saturn breathes the winds that
might prove to be the lifeblood of the
system thrum and flow across its
atmosphere its delicate balance of
magnetic fields and gravity coax at its
rings keeping them perfectly aligned
Saturn's rings are thought to be
surprisingly young Saturn may be over 4
billion years old but there is evidence
that the Rings may have only formed in
the last 100 million years and they are
slowly draining back down into Saturn's
atmosphere so in another 100 million
years they may be gone this is sad to me
but I also feel strangely fortunate if
Humanity hadn't arrived when we did we
might have missed this beautiful Cosmic
site it may be unscientific to say that
as a planet has no real choice in
whether it gives us a gift or not but
I'm nonetheless grateful to have been
witness to the enigmatic and wondrous
world that is Saturn and seeing those
enigmas and wonders all the beauty all
the scientific data just would not have
been possible if it had not been for the
incredible Cassini ho
This truly was one of the greatest space
missions of our time Jupiter a place of
colossal storms deadly radiation and
captivating Beauty a Powerhouse whose
mass is so great it influences even the
sun
itself Jupiter is fast becoming one of
the most studied objects in our solar
system with seven flybys two orbiters
with one still in operation today and
two additional plan missions there is so
much to know about the fifth planet from
the Sun what causes its distinctive red
coloration what is it made of What Lies
Beneath its obscuring clouds what do we
know about its Great Red Spot Jupiter
holds a vital role in protecting our
solar system and it's time to delve into
its Mysteries
I'm Alex molan and welcome to astram
join me today as we explain everything
you could want to know about
Jupiter the fifth planet from the sun
Jupiter is found on the outskirts of the
asteroid belt and sits between the
orbits of Mars and Saturn it is
778 million km away from the sun on
average or 5.2 astronomical units and
completes an orbit every 12 earth years
the axal tilt of the planet is small
only
3° this means it doesn't experience much
change in Seasons unlike Earth and Mars
and very much like Saturn its radius at
the equator is greater than at the poles
it is a massive Planet the largest in
our solar system it is so massive its
mass is a thousandth that of our sun
that might not seem like a lot but once
you realize the sun contains
99.86% of all the mass in the solar
system you'll realize that Jupiter
equals almost the remainder its mass is
2 and 1 half times that of all the other
planets in the solar system combined and
this brings about an interesting
phenomenon the Barry Center between
Jupiter and the sun is actually above
the surface of the Sun at
1.68 solar radi from the Sun Center
let's talk about baric centers when we
think of an object orbiting another
object we don't necessarily think that
the smaller object has a gravitational
influence on the bigger object that's
because most of the time the effect is
negligible like the ISS orbiting Earth
or even Mercury orbiting the Sun but it
does still happen a baric center is the
center of mass between these two
orbiting object objects or the location
in space they both orbit around with
Jupiter being the mass and distance from
the Sun it is unlike Mercury its effect
is far from
negligible as Jupiter swings around the
Sun both of them do a little dance
around this Center of mass which is
actually above the surface of the Sun
let me show you this principle with an
example if I get a heavy object and a
less heavy object object and attach them
to the ends of a long stick in order for
the stick to balance we need to find the
center of
mass as you can see the center of mass
is closer to the heavier object imagine
this is the Sun and Jupiter with the
stick being gravity and you'll
understand how a bar Center
Works while Jupiter has the greatest
mass of any planet in the solar system
it's not the densest it is the most
massive because it is the largest if
Neptune was the same size as Jupiter it
would be the most massive and if Jupiter
was the same size as Earth Earth would
be over four times more massive as it is
though the diameter of Jupiter is 11
times that of earth and its total mass
is
318 times more than Earth's as we know
Mass affects gravity this means that
Jupiter has a huge gravity over twice
that of Earth at
2528 G at its surface the gravity of
Jupiter is so influential in the solar
system that it affects every planet to
one degree or another its gravity is
strong enough to tear asteroids of heart
and capture 67 moons at
least some scientists think that Jupiter
destroyed many celestial objects in the
ancient past as well as preventing other
planets from forming one example of this
in particular is for
Vester scientists even predict the
gravity of Jupiter is so significant
around the solar system that it is
perturbing Mercury's already eccentric
orbit enough that in a few billion years
the tiny planets May either crash into
the Sun or be ejected from the solar
system
altogether at the moment though it could
be the hero of the four inner planet
without Jupiter acting as a cosmic
vacuum
it wouldn't be sucking up dangerous
objects like long period comets or
perturbing their orbits enough to give
them a little kick of energy so that
they leave the solar system all
together Jupiter is the fifth planet
from the sun and it's five times further
away from the Sun than Earth even so it
can be the third brightest object in the
night sky after the moon and Venus I
just want to show you how bright that is
is just using a handicam we can see
Jupiter quite easily in the night sky
with a maximum magnitude of minus
2.94 it can actually cast
shadows as a result of it being so
obvious in the sky it makes a very nice
Target for amateur astronomers as
consumer telescopes have improved in
recent years it's amazing what details
you can see from your back garden and
what makes these famous patterns
the cloud layer is only about 50 km
thick and contains ammonia crystals much
like on Saturn but the coloration comes
from compounds heating up from deep
within Jupiter and then Rising these
compounds are known as chromophores and
when they reach the clouds they interact
with the UV light of the sun to create
these spectacular multicolored bands
this is quite the cycle though and the
face of Jupiter can change dramatically
over time even if their colors do change
the actual latitude of these bands
remains consistent enough to be given
identifying designations but they can
vary in width over the course of time
lots of Storms and turbulence occur
where these bands meet and it is the
reason and engine behind Jupiter's very
famous Great Red
Spot this storm is huge it can easily
fit the diameter of Earth within it it
is a existed for as long as we've known
since it was first discovered in the
17th century it might very well be a
permanent feature of the planet but
interestingly it has decreased in size
since observations began the reason for
its redish color is unknown and the
color of the spot can vary greatly from
brick red to Almost White the most
recent theory for its color is chemical
compounds being broken up by the UV
light from the sun much in the same way
as the process that happens on the rest
of the planet the storm is actually much
higher up in the atmosphere than the
surrounding clouds and as a result can
interact with the sunlight a lot more
this would explain why its color can be
much stronger than anything else around
it but Jupiter doesn't just have one
scientifically interesting storm another
storm known as red spot Jr formed when
three storms merged into one between the
years of 1998 and 2000 and it has so far
passed unscathed by its bigger neighbor
and is now quite a prominent feature of
the planet it could last for another
couple of hundred years if it avoids the
same fate of a similar storm which
passed right through the heart of the
great red
spot so what do we think Jupiter is made
of well much like Saturn under the
atmosphere are Gus then liquid and then
in metallic forms of hydrogen the
further into the planet you go the
greater the pressure becomes under
immense pressure hydrogen acts as a
metal and beneath that is an ice or a
rocky core because we can't recreate on
Earth the immense pressures Jupiter
experiences we don't really know what
properties these materials have at the
core roughly 90% of Jupiter is thought
to be hydrogen 10% helium and then R
amounts of methane ammonia and others
Jupiter rotates very fast faster than
any other planet completing a rotation
in only 10 hours but due to it not being
solid it doesn't rotate the same speed
all over a rotation at the poles taking
5 minutes longer than at the
equator as a child I was very curious
why Jupiter wasn't a star considering
Jupiter is so massive plus it is
predominantly made of flammable hydrogen
surely someone just needs to throw a
match in to set it a light well the sad
news for my inner child is that stars
don't really work that way plus there's
barely any Oxygen on Jupiter to allow
for combustion stars produce their heat
from nuclear fusion caused by the
extreme pressures found at the stars
core current thinking is that Jupiter
would need to be roughly 75 times more
massive than than it is now to be
massive enough to be a star although
interestingly its volume isn't too far
off from the smallest known Red Dwarf
and yes you may have noticed in this
picture Jupiter does indeed have rings
nothing on the scale of Saturn but there
are four planetary Rings the main ring
is very thin but very bright the rest
quite wide but exceptionally faint the
main ring is about 6,000 km wide and the
only distinctive feature you will see is
what is known as the metis
notch something else to note about
Jupiter is its remarkably strong
magnetosphere it is 14 times stronger
than Earth due to the planet's liquid
metallic hydrogen Center this makes it
the strongest magnetosphere of any
planet in the solar system and is only
beaten by the sun's
sunspots there are a couple of reasons
why this is really interesting the first
is that magnetospheres channel solar
wind to the planet's pole which produces
magnificent Aurora the second is that
the four biggest moons of Jupiter are
protected from this solar wind because
they orbit within the magnetosphere this
implies they don't need their own strong
magnetospheres because Jupiter is doing
that for them however this doesn't mean
they are safe from radiation Jupiter has
a powerful radiation band around it the
same radiation band that has crippled
any probe that went through it the
closest large moon to Jupiter IO passes
right through the heart of this
radiation band receiving 3,600 Ram per
day on the surface for a point of
comparison anyone exposed to this much
radiation would be dead within 4 hours
not the best home away from home then
when it comes to the Jovian moons I'll
only very quickly talk about them
because I have made a separate video
about them here Jupiter has 67 known
natural satellites 51 are under 10 km in
diameter but the largest the Galilean
moons are some of the biggest in the
solar system they are IO Europa ganam
and Kalisto and they are all interesting
in their own right ganam is actually the
biggest moon in the solar system and has
a greater diameter than that of
mercury and with this final thought take
a look at Jupiter through the infrared
demonstrating the immense size and power
of this planet this dot at the bottom of
the planet is the impact of an object
from space which if it had hid Earth
could have spelled the end of our planet
as we know it we can be glad Jupiter is
there not only for its beauty but
because in so many ways it is an asset
to our solar
system thank you so much for watching
this far did you learn something today
about Jupiter you never knew before and
what planet remaster would you like to
see next on this channel for this series
let me know in the comments below and
I'll see you next
time Uranus the ice
[Music]
giant this C bluish gray marble seems
like a desolate waste in the far reaches
of the solar system but in actuality
there are some fascinating facts about
this planet which make it unlike
anything else in the solar
system I'm Alex molan and you're
watching astram stick with me on this
journey and we will explore almost
everything you could want to know about
Uranus the first unique aspect of Uranus
is its name all the planets are named
after Roman gods except Uranus it's
named after the Greek god of the sky
oranos the latinized version of this
word is what we use today had they just
kept the Greek version it might have
saved a bit of embarrassment as people
stumble over saying Uranus in a polite
way it even has two ways to pronounce it
as no one has been able to definitively
agree on the matter Uranus and
Uranus Uranus is also very special in
the way it rotates and orbits it is the
seventh planet from the sun the second
from last planet it orbits on average
around 19.2 astronomical units from the
sun which means it is over 19 times
further away from the Sun than our Earth
this varies throughout its year by 1.8
astronomical units the biggest
difference of any Planet being this far
away from the Sun means it is freezing
cold-
220° C cold which makes it the coldest
planet in the solar
system its year lasts 84 earth years
when it was first discovered astronomers
attempted to predict its orbit after
some time though they realized it hadn't
followed their predictions and concluded
that the reason was because there was
another planet that had a gravitational
influence on it they mathematically
predicted where this planet should be
and as a result Neptune was discovered
interestingly the same Theory surrounds
this as yet undiscovered Planet X or
Planet
9 some far out objects in our solar
system are not where they should be and
Theory suggests this is because of
another planet that has a gravitational
influence on them the Hunt is now on to
actually find this
planet what's really interesting about
Uranus is its
rotation most planets rotate like a
spinning top on the table of the solar
system plane not Uranus no Uranus has
fallen over and is rolling instead for
large portions of its year you see its
axle tilt is
97° this means its seasons are crazy in
comparison to the rest of the planets
during its Solstice or the time of year
when the sun is highest or lowest in the
sky one hemisphere of the planet always
faces the sun while the other is in
complete darkness
it kind of looks like the planet is
rolling along its
orbit only a very narrow strip near the
center of the Equator of the planet
experiences day and night during this
time but the sun does only just Rise
Above The
Horizon the poles on the other hand get
42 years of continuous Darkness followed
by 42 years of
daylight during its Equinox which is the
opposite of a solstice the planet has a
more normal day night
cycle Uranus is currently leaving its
Equinox having passed it in 2007 and is
now heading back towards a
solstice Uranus rotates once every 17
hours and 14 minutes because its surface
is not solid however some parts of the
atmosphere rotate faster than others and
due to high winds some sections can make
a full rotation of the planet in only 14
hours
this strange rotation and axel tilt
means it is the only planet in the solar
system that gets more energy from the
Sun at its poles than at its equator on
average for some reason though the
equator is hotter than at the poles and
no one really knows why speculation also
exists as to why Uranus rotates the way
it does in the first place although it
is generally accepted a large
earth-sized planet crashed into Uranus
knocking its rotation on its
side how big actually is
Uranus well it is the least massive of
the gas giants at 14.5 Earths compared
to Neptune's 17 Earth masses its
diameter though is just bigger than
Neptune's at
50,7 km about four times more than
Earth's because this mass is spread out
over a large area the gravity on Uranus
is only slightly less than on Earth at
7.8 m/s squared or 0.89 G's that would
feel quite
comfortable and what is it made of well
it is believed to have a core just
smaller than Earth of Rocky silicate
material which is surrounded by a mantle
of water ammonia and methane ices
although it's referred to as ices this
mantle is in fact very hot reaching
almost 5,000 de C and is more like a
liquid ocean surrounding the core so to
call Uranus a gas giant is a bit
disingenuous it is certainly not gaseous
all the way through the atmosphere is in
fact very insubstantial in comparison
only consisting of a total of 0.5 Earth
masses with most of the mass of Uranus
being in this core and mantle the
atmosphere is comprised of mostly helium
hydrogen and 2.3% methane and then a
cloud layer on top
it's this methane that gives Uranus its
aquamarine or cyan
color very interestingly some models
suggest that pressure at the base of the
mantle on Uranus is enough to break the
methane molecules apart which then
compresses the carbon atoms from the
methane into diamonds these diamonds
rain through the mantle like
hailstones the very base of the mantle
could be a layer of liquid diamond or
carbon with solid diamond Burger
floating in
it we'll fly away from the planet just a
little bit now to have a look at its
planetary ring system Uranus much like
the other larger planets in our solar
system has rings it has 13 very dark and
young Rings most are not bigger than a
few kilometers wide and they are thought
to only be 600 million years old much
younger than Uranus they are comprised
of extremely small particles the biggest
being only a few kilometers across made
of water ice and dark radiation
processed Organics their alido doesn't
exceed 2% or in other words they are
darker than wet
soil as we'll see shortly Uranus has a
lot of moons and the Rings are thought
to be the result of high impact
collisions with some moons in the past
it is unclear why some of the Rings are
kept so narrow the usual explanation
being that the Rings are kept in by
Shepherd moons but this is only the case
for one of the Rings
here Uranus was discovered to have rings
in
1977 when an occultation of a star
occurred the star dimmed a few times on
either side of Uranus as Uranus moved in
front of it confirming the presence of
rings Uranus has only been visited by
spacecraft once and that was in 1986 by
Voyager 2 Voyager 2 discovered a lot of
the Ring and moons of Uranus giving us
close-up shots of the faint ring system
when Voyager flew by though this only
brought the total of known rings to
11 when Hubble was launched it also had
a look at Uranus discovering two
additional rings that had never been
seen before the outermost ring is twice
as far away from Uranus as the
previously thought outermost
ring and as promised here is a look at
the many moons
and usually the moons are named after
figures in English literature overall
Uranus has 27 known moons divided into
three
categories the 13 inner
moons five major
moons and nine irregular
moons the inner moons are connected with
the rings of Uranus some of which may
have provided the Ring's
materials the largest of these moons is
called Puck at only 162 km in diameter
it is the only inner moon to be captured
in detail by Voyager
2 interestingly these inner moons
constantly perturb each other and the
system is very unstable there's a good
chance that some of them may Collide
again in the
future the five biggest moons in order
of distance from Uranus starting on the
left are Miranda Ariel umel Titania and
Oberon Titania is the largest moon of
Uranus and the eighth largest moon in
the solar system at 1,600
km again as can be seen these are very
dark objects umal being the darkest with
the exception of Miranda which is
comprised mainly of water ice the rest
are thought to be a mix of water and and
Rocky
materials these moons may have
differentiated Interiors meaning a core
of Rocky material with a mantle of ice
between the core and the mantle could
well be an ocean layer of liquid
water interestingly the axal tilt of the
large moons is the same as Uranus
meaning that during Solstice if you were
to look at the sun it would only ever
move in a circle in the sky never
setting during solstice only one side of
the moon faces the sun meaning a
constant
daytime the final nine known moons are
irregular moons they are likely to be
captured objects and are much further
out than the last of the big moons
Oberon they vary in size from 20 km to
the biggest pyox which is about 200 km
in
diameter finally let's explore Uranus's
climate and magnetic
osphere Uranus the seasons are quite
unique in the solar system due to its
exceptional axle tilt telescope
technology has only allowed us to
resolve details on the surface of Uranus
for the last few decades which means
it's difficult to be able to say with
certainty if there are changes between
Uranian years what has been observed
though is that as the planet approaches
Solstice the pole brightens and a color
forms moving away from Solstice the pole
and color dim
this brightness is thought to be due to
the thickening of methane clouds
although the cause is not clear Seasons
also affect storms in the upper
atmosphere storms are relatively rare on
Uranus compared to other gas giants but
are thought to be caused by changes in
the
seasons with the improvements in
telescope technology we have also been
able to observe bands stretching around
the planet much like the other gas
planets however these bands are mainly
visible in the infrared which is why
Voyager was only able to show us this
invisible light in these infrared images
you can also see small storms dotted all
over and another unique feature of
Uranus is its unusual
magnetosphere usually magnetospheres
originate from the geometric center of
the planet but that's not the case with
Uranus also it's not in line with the
rotational axis but is 59° off this
unusual placement means the
magnetosphere is much stronger at the
North Pole than at the South one theory
for this is the liquid Diamond ocean
could deflect the magnetosphere or even
that it is not the core of the planet
that produces the magnetosphere at all
but rather the liquid mantle the
magnetosphere is about as strong as
Earth's and because of its unusual
rotation the Magneto tail cork screws
off for millions of kilometers into
space look up into a clear night sky
with your naked eye and what planets
would you
see technically you would be able to see
all of them at one time or another all
of them apart from
Neptune it is the smallest of the gas
giants and also the furthest away and it
is a perplexing place you would think a
planet so far from the Sun wouldn't have
a dynamic atmosphere that exhibits
ginormous storm STS and super fast winds
and yet it
does so why is this planet as
interesting as it
is I'm Alex molan and you're watching
Asam and today we're going to delve into
everything you could want to know about
Neptune let's start right at the
beginning Neptune is the only planet
found through mathematical prediction
you see when Uranus was discovered and
astronomers were plotting its orbit they
noticed that Uranus wasn't following
their models from the perturbed orbit of
Uranus Ian leier in
1846 concluded that there must be
another undiscovered planet and he
predicted where it should be and
remarkably Johan gal was able to find it
only a degree away from the predicted
Point Triton Neptune's biggest moon was
discovered a few days later but since
since then Neptune has been poorly
understood as its distance from Earth
and very small apparent size meant it
couldn't be studied from groundbased
telescopes very easily it wasn't until
1989 when Voyager 2 arrived that huge
amounts of information about the planet
became
available suddenly we could see what the
planet looked like confirmed that it had
planetary rings and discovered a lot of
previously unknown
moons but let's get to today what do we
know about this planet
now since Pluto's demotion to not a
planet status Neptune is the eighth and
furthest planet from the sun it orbits
at 30 astronomical units from the Sun on
average which means it's 30 times
further than the earth orbit from the
Sun 30 astronomical units in other words
is 4.5 billion km and from that you can
see why it would take space probe using
current technology 13 years to reach
Neptune 4.5 billion kilm is a
considerable
distance because of this long orbit it
takes a
huge 165 years to orbit the sun once
which means we've only seen one
neptunian year since its Discovery this
distance from the Sun means the average
temperature in Neptune's atmosphere is
very cold- 20 1° C its axle tilt is 28°
meaning it's similar to Earth and Mars
which have 23° and 25°
respectively this means it has Seasons
similar to Earth of Ms 2 the big
difference being these four seasons last
40 Earth years each at this moment in
time the southern hemisphere is
experiencing spring during this spring
the southern hemisphere receives more
sunlight and appears brighter this
increase in brightness is actually quite
noticeable which is strange as you would
have thought that because the sun is 900
times dimmer on Neptune than on Earth
from that distance it wouldn't make much
of an impact but even if it is only a
small impact it makes an impact
nonetheless and the increased sunlight
levels in the southern hemisphere warm
it up by about 10° C compared to the
rest of the planet this comparably
higher temperature releases Frozen
methane into the stratosphere causing
its increased brightness whereas
Elsewhere on the planet it remains
Frozen and stays deeper in the
troposphere just a quick recap of the
Spheres of a planet the troposphere is
the lowest atmospheric level followed by
the stratosphere above those layers are
the mesosphere the thermosphere and then
the exosphere but that's a very
interesting topic in itself and we'll
save it for another
video if you look at the weather on NE
June it actually has the fastest wind
speed of any planet with wind speeds
blowing Westward on the equator reaching
a staggering
2,160 kmph nearly a supersonic flow and
interestingly most winds travel
retrograde to the rotation of the planet
bands are also formed on the planet as
well as colossal storms when Voyager 2
passed by the planet in 1989 it saw the
Great dark spot a storm about the size
of Earth passing through its atmosphere
Voyager also saw the smaller storm known
as the small dark spot south of its big
sibling as Voyager 2 approached Neptune
this smaller storm changed in shade from
dark to light when Hubble was launched
astronomers were curious to see the fate
of these storms to see if they were a
permanent feature like Jupiter's Great
Red Spot but when Hubble was pointed at
Neptune in 1999 these storms had
completely disappeared and storms have
come and gone ever since giant bright
high altitud clouds also come and go but
why then doesn't Uranus which is very
similar in composition and size to
Neptune also have such a blustery
atmosphere don't get me wrong wind
speeds on Uranus are fast too but it
doesn't compete with Neptune at only 900
kmph can all this only only be due to
interactions with the sun and its
Seasons something else must be at play
here to explain the Extremes in
weather the answer May lie deep beneath
Neptune's
surface I mentioned that Neptune is the
furthest planet from the Sun so you
would have thought it's also the coldest
but actually Uranus is the coldest
planet in our solar system Neptune
radiates heat from within whereas Uranus
radiates hardly any excess heat at all
this could be because a large
earth-sized body crashed into Uranus
billions of years ago which depleted all
of its primordial heat astronomers now
theorized that the more active weather
on Neptune might be due in part to this
higher internal
heat what is Neptune actually made of
then its internal structure and
atmosphere is thought to be very similar
to Uranus its atmosphere is composed of
mainly 80% hydrogen and then 19% helium
with very small amounts of methane it's
this methane though that gives Neptune
its blue color although it's a darker
shade of blue compared to Uranus's Canan
again like Uranus there is a liquid
mantle of water ammonia and methane Isis
surrounding the core and where the core
and the mantle meet the pressure is so
great that the methane may break apart
and diamonds are formed under the
pressure likely not diamonds as you or I
know but there could be a liquid carbon
ocean with solid diamond burgs floating
in it and diamonds raining down through
the manle like
hailstones this is just a theory though
as technology has only recently started
to recreate such pressures around the
core of Neptune it's thought to be 7
million bar or 700 Gap pascals which is
about 7 million times the pressure of
Earth's atmosphere at the surface even
the two ice giants magnetosphere share
similarities Neptune's magnetic field is
offset 47° relative to its rotational
axis when Voyager 2 discovered this
about Uranus the first theory was that
it had something to do with its unusual
axle tilt but then it found the same
thing out about Neptune which has a more
normal axle tilt so the current theory
is that the magnetic field is either not
generated in the core but rather by an
electrically conducting liquid mantle or
that the mantle deflects the magnetic
field from the core which gives it this
weird offset in relation to its
rotational axis every planet in the
solar system hasn't actually got a
perfectly aligned magnetic field even
Earth's magnetic north is different from
where the North Pole actually is but
it's only Uranus and Neptune that have
such a tilted
magnetosphere Aurora do exist on Neptune
2o but they are different from what you
might expect as they are extremely faint
due to particles not getting as charged
from the Sun and because of the
direction of the magnetosphere they are
mainly type B Aurora or SAR arcs Earth
gets these too but they are not visible
and you need scientific instruments to
know that they are there they could be
stretching across the whole sky without
you actually knowing about it another
difference with the SAR arcs of Neptune
is that they are not only found around
the poles but rather are around the mid
latitudes of the planet
zooming out from Neptune a bit we come
to its ring system like all other gas
giants Neptune does have a ring system
although it is extremely faint as it is
not as dense and is extremely dark in
color if you have these Rings against
the black backdrop of space and also
have them be this far away from the Sun
then they are very hard to see but there
are five known rings in all and they are
named after people involved in the
discovery and re research of Neptune the
innermost is the gal ring which is very
faint and very wide at 2,000 km next is
the first bright ring
leier although it's bright it's only 113
km wide next and connected is the lasso
ring a very faint band 4,000 km across
on the edge of this ring is the arago
ring it is slightly brighter than the
lasso ring and less than 100 km wide
lastly is the outmost and the most
researched ring the Adams ring it is
only 35 km wide but is one of the
brightest Rings it is particularly
interesting as it is slightly inclined
and has bright arcs in it these arcs
have been quite stable since they were
discovered in 1980 but usually planetary
rings are uniform throughout these arcs
must be material clamping and clustering
up within the ring but the reason for
this is currently
unknown lastly I want to talk about the
moons Neptune has 14 known moons which
are named after water deities in Greek
mythology the most famous and the
largest by far is the Moon Triton which
actually contains most of the mass of
all of Neptune's moons put
together I personally think it is one of
the prettiest moons in our solar system
as it has amazing patterns and this
burnt orange color what is most
interesting about Triton is the fact it
orbits in retrograde and also at an
inclination to Neptune's rotation which
implies it is probably a captured object
and not something that was formed
alongside the planet Triton might be the
cause of the Rings of Neptune as it
would have disrupted the orbits of moons
possibly causing them to collide and
break up into what is now the rubble of
the Rings Triton is even bigger than
Pluto and also has a tenuous atmosphere
Voyager 2 even saw faint clouds on its
flyby of the
Moon the next biggest moon is proteus
which is a little irregular in its shape
normally we only see this on smaller
objects like asteroids but Proteus is
actually bigger at 400 km across than
the spherical Moon of Saturn
mimus why it is not a sphere is
explained by past collisions of things
hitting the moon leaving these massive
crators which you see
the inner regular moons orbit around the
Rings some acting as Shepherd moons the
outer irregular moons are all likely
captured moons some of the irregular
moons orbit prograde and others
retrograde the outermost moons of
Neptune are Sam and netho and are the
furthest out satellite of any planet
that we know of to date they take a
massive 25 years to orbit Neptune only
once
this is because Neptune has a very large
Hill sphere the hill sphere being the
sphere in which the planet's gravity
overcomes the gravity of the sun it is
such a large Hill sphere because it's
already so far from the Sun the Sun's
gravity has less of an influence around
Neptune than at the biggest planet
Jupiter well thank you for watching did
you learn something interesting about
Neptune today what Mysteries would you
like to see solved we're still working
our way through remastering the planets
in our solar system series what planet
would you like to see us do next let us
know in the comments below and I'll see
you next
time thanks for watching and thanks to
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