ever feel like you just don't fit the mold well meet ceres since its discovery in 1801 ceres has
been considered a comet a planet an asteroid and a dwarf planet starkly different in appearance from
its rocky neighbors ceres was always an unusual planetary body within its belt but when telescopic
images revealed mysterious bright regions on its surface scientists wanted to delve deeper
into the answers a closer view might unveil after the arrival of the dawn space probe in 2015 those
answers came quickly and scientists found this small world was holding some very big surprises
In 1801 Giuseppe Piazzi spotted ceres and assumed it was the missing planet between mars and Jupiter
by 1860 61 other planetary bodies were discovered in the region and three years later astronomers
reclassified these bodies to asteroids and aptly named the area the asteroid belt
for the next 140 years ceres would be known as an asteroid that all changed in 2006 when astronomers
noted that ceres actually match the same criteria used to classify Pluto and similar sized objects
in the outer solar system so just like Pluto ceres was reclassified as a dwarf planet
and it would soon become the very first of its kind to be orbited by a spacecraft named after
the roman goddess of corn and harvest what makes this cosmic body so fascinating is the fact that
it is the only dwarf planet without any moons and although it is the largest object in the asteroid
belt between mars and Jupiter ceres has a radius of only 296 miles to put that into perspective if
our earth were the size of a nickel ceres would be about the size of a poppy seed
shortly after the arrival of nasa's dawn space probe scientists knew that
some absolutely amazing geological activity was taking place on ceres
after completing its primary mission don moved closer to series and photographed images of
two distinct highly reflective areas within the Occator crater a 60 mile wide scar in
series the surface the two bright focus areas were named serelia facula and vinalia faculae
planetary scientists got a startlingly close look at the geology and composition of Occator
as is common activity on planets micrometeorites frequently pelt the surface of ceres
which meant those white spots should have darkened over time so the extraordinary
brightness of the two areas within the octet or crater were indicative that the area was young
series okada became the main focus of dawn's final extended mission from 2017 to 2018
with close-up images those mysterious bright regions
slowly began creating more questions questions that opened up to scientific breakthroughs
from the onset it was clear that the bright areas were sodium carbonate deposits
this was evidence of past water activity which had percolated to the surface and evaporated
causing a highly reflective sheen of a salty crust over series surface was there liquid
still hiding underneath a salty ice crust and if it was where had the water come from
two competing theories emerged some scientists hypothesized that the salt crust was a result of
the impact that had created the occur crater other scientists looked at the possibility that fluids
had existed on the dwarf planet long before an impact created the crater if this were in fact the
case it would mean that the fluid was still there bubbling underneath the surface of ceres such a
discovery could change how planetary scientists view icy moons and frozen planetary bodies
as dawn dipped closer to the surface crisper details of the white areas emerged scientists
discovered unmistakable infrared signals of what they called the smoking gun hydrohalite
hydrohalide is composed of sodium chloride regular sea salt surrounded by water molecules
the existence of sea salt on a planet besides earth is a monumental discovery
and signified evidence that liquids still existed on ceres but how did the water come
to settle in the bowl-shaped crater was this mysterious dwarf planet only home
to pockets of liquid or could it possibly be a spectacular global ocean now frozen over
scientists delved into imagery to unlock answers on whether the closest dwarf planet to earth
may have once been a habitable world or at the very least held the prowess to one day become so
to understand series and the peculiar events unfolding just within its icy shell scientists
needed to go deeper with the application of gravity measurements the density of series
crust was mapped as a function of depth a first for an ice rich planet this helped scientists
learn more about the internal structure of the dwarf planet and furthermore determined that
the brine reservoir was 25 miles deep and hundreds of miles wide but that's not all scientists found
that ceres crust density increased significantly with depth which was beyond the capability of just
pressure researchers inferred that as series water freezes a combination of salt and mud
incorporated into the lower part of the crust with the blemishes in series surface along with
sullen features scientists reasoned that ceres was once home to a global ocean that had frozen over
could that mean that life existed before a cold wave hit the planet burying it under the icy brine
the hidden ocean underneath series icy shell signified endless possibilities as the water
wasn't completely frozen planetary scientists concluded that geological activity at Occator was
ongoing causing water to seep out to the surface there were two main pathways that could cause
liquid to reach the surface at the larger deposit of serialia salts bubbled from a slushy area just
underneath researchers hypothesized that this icy mixture melted as a result of the impact heat that
originally created the crater some 20 million years ago they believe the impact heat subsided
over the next several million years but the large fractures continue to maintain a connection with
the long-lived reservoir deep within the crust apart from the serialia the vinalya faculae
also garnered attention its thinner brighter spots also pointed to the existence of salts
the difference between the two regions was the depth of the liquid source welling up
from within ceres and further differentiated the brightness of both areas liquid rose through the
thinner fractures and froze leaving behind salt deposits that varied in view from the serialia
on the series surface mixtures of salt and water quickly dehydrate but don's measurements show the
planet still has water deep within so the fluids must have reached the surface very recently this
is not only evidence for the presence of liquid below the region of the occur crater but also
geological activity causing an ongoing transfer of material from the deep interior to the surface
series was full of surprises and soon scientists made another breakthrough discovery an assortment
of interesting conical hills hills reminiscent of the small ice maintained in polar regions of the
earth these conical ice mountains are formed by pressured groundwater that has frozen over
although these conical icy hills had previously been spotted on mars it was the first time a dwarf
planet displayed these distinct features icy geological activity more commonly only exists
on icy moons and is caused by the gravitational pull of their respective planets in the outer
solar system moons interact with the gravitational forces of their larger planets causing internal
heating some bodies like Jupiter's moon io generates internal heat in a similar manner
in a process called tidal heating this process is what leads to the evolution of such worlds
but mid-sized cosmic worlds don't experience these gravitational interactions or do they
dwarf planets like ceres have ice cold hearts with no available conditions to facilitate tidal
heating the core remains cold it also owns no atmosphere which is required for trapping heat
without heat naturally the water should have frozen over completely ceres didn't benefit
from this internal heating it is an ice-rich planetary body a water-rich world not a moon
interacting with gravity of a dedicated planet is it a moonless planet itself why was the old
ocean that encompassed ceres still not completely frozen data and images from scientists show that
other cosmic bodies also maintain liquid water over eons how the answer lies in the existence
of salt and compounds like the smoking gun on ceres hydro halite the impact event 22 million
years ago and the generation of extreme heat that followed was the chief driver of icy evolution
the mill chambers these impacts created could possibly be transient habitable chambers nasa
believes that these chambers provide a chance for life to arise in frozen ocean worlds and icy moons
as we explore the far reaches of our solar system we are beginning to learn that ocean worlds are
more frequent than previously thought there is enceladus saturn's snowball moon and the
galilean moons ganymede and europa which are believed to harbor internal oceans
in 2016 researchers even found evidence of a global liquid ocean underneath the frozen shell
of pluto at the edge of the solar system there is a plausible belief that more potentially habitable
objects like ceres could exist we know that where there is water there is potential for life
nasa's dawn mission gave the world an inside track and observing further ocean worlds will
enable scientists to assess habitability and discover life or remnants of past life
to determine whether ceres currently harbors life or once did
the environment needs to be studied further and for that scientists need a lander mission
a study is being finalized for submission to nasa
that would see a sample return mission to series specifically the venalia faculae area
scientists want to assess habitability and study organic matter that exists on the surface
whether this mission will be accepted and executed by nasa's long-term planning committee
will be determined in 2022 astrobiologists have their sights set on mars as the prime target for
missions to find signs of ancient life but ocean worlds might also provide refuge for alien forms
after some of the biggest revelations in space and forging new ideas of existence
of life on icy planetary bodies scientists look ahead and plan missions to icy planets
astrobiologists believe that if anything is found to be living on ceres it's likely to
be small microbes similar to bacteria if it does not harbor living organisms today
there are still very strong signs that it would have harbored life in the past
julie castillo roger conducted the data analysis for nasa's dot and believes
that this is just the beginning a planetary scientist specializing in water-rich planetary
bodies castillo roger has invested two decades into studying icy worlds in our solar system
she believes that the data analysis for nasa's dawn is just the beginning as so many new
questions were born after the don mission it's interesting to note that the results derived from
Occator only converted a fraction of the data that was beamed back from the dawn in its final days
as it used up the last of key fuel hydrazine dawn lost control over its orientation it could
either point to earth for communications or point satellites at the sun for production of electrical
power with organic matter on series surface and liquid right beneath the surface planetary
protection rules forbade dawn from crashing into the surface and risking contamination that is why
don was placed in long duration orbit the probe on a lonely vigil that will likely continue for
the next two decades when scientists finally return to series for samples of the surface
dawn will still be orbiting overhead a monument to past success so what do you think should we go
back with a lander mission tell us in the comments thanks for watching we'll see you next time