our world and beyond space in
partnership with the European Space
Agency
the mercury of Roman mythology was an
erratic and volatile character and this
swift-moving messenger lent his name to
one of the solar system's most
mysterious worlds the planet mercury
mercury is really a weird planet
normal terrestrial planets all the rest
have a relation between the how big they
are how then they are America is not
following that rule is much more dense
that what you would expect for its size
so something went wrong in the formation
of mercury that we don't know one of the
reasons why mercury remains mysterious
is that it's so close to the Sun
telescopes find it difficult to observe
a small planet against such ferocious
light
mark you must know it's the missing
piece in order to understand the
evolution of our solar system we have
been to comments we have seen the other
planet but we do not know a lot about
mercury
what we do know points to a forbidding
world pockmarked with craters
luxury for us is a planet of extremes as
a hottest temperature as temperature
variations on Mercury about 600 degrees
between day and night so you have
temperatures like 400 450 degrees on the
surface during the day and imagine
that's like being in app itself runner
so it's really hot there and
temperatures at about minus hundred
seventy-five doing tonight one of the
great mysteries of mercury is its orbit
and rotation it follows an unusual
pattern one day on Mercury can last up
to a hundred and seventy-six Earth days
and yet one year last 88 Earth days
nicola combo from the observatory of
Paris has spent years researching the
rotation of mercury
there in 10 or the rotation of mercury
is really unique solar system mercury
rotates two times around the Sun in the
time that it turns three times around
its polar axis this one expert
mercury follows an odd elliptical orbit
in which it passes within 47 million
kilometers of the Sun and then swings
out to 70 million kilometers while it
rotate slowly on its axis meaning the
passing of a day on mercury is like no
other
so that's what happened manicure if they
were on the planet Mercury what you
would see is the Sun rising in the East
today offered the then it would climb
into the sky and then the Sun would stop
at a certain point and wanted off that
move slightly backwards on ya stop again
and then carry on and set in the West
the way mercury turns on its axis
suggest that just beneath its thin
silica crust lies a large fluid mantle
it's so dense that scientists believe it
must be made from molten iron blended
with a little sulfur
and as for atmosphere too masculine part
by the mercury we don't talk about an
atmosphere but instead we talk about an
exosphere that's to say something which
is very tenuous basically linked to
outgassing Judah solar wind so there are
a few particles that are around mercury
but it's very very thin before the first
space probes flew to mercury some only
assumed it was a rather dull planet
simmering in the heat of the Sun Mercury
is known since long time ago I mean dish
Egyptians already give information about
about the existence of mercury and and
recognizing it as a planet but but real
observations of Mary didn't started much
later the first signs that mercury was
more mysterious than imagined came when
the mariner 10 mission flew by in 1974
it sent back intriguing images of the
surface and picked up signs of a weak
magnetic field
since 2011 the NASA probe Messenger has
been orbiting mercury mapping the
surface in detail
it's picked up signs of ancient
volcanoes and of a cooling interlayer
yet so much remains to be discovered
what scientists want to do is try to
understand the nature of the planet
itself you want to characterize the
surface what material is under surface
we would like to measure temperatures we
would like to see the interaction with
the solar images special American
because it's so close to the Sun then
were curious and magnetic field which is
like Earth dynamo field we would like to
understand that and so there are several
reasons to go to mercury
in 2015 Europe should launch its own
mission to mercury it carries the name
Betty colombo in honor of the italian
mathematician he studied mercury and it
was his calculations which helped plot
the course of the mariner 10 space craft
Betty Colombo's first challenge is to
successfully reach its destination and
avoid the gravitational grasp of the Sun
the Sun has a lot of gravity and if you
get in out of our orbit Earth orbit and
you go closer to the Sun and you want to
get to the mercury orbitz you have to be
very careful and expend a lot of energy
to avoid falling in the Sun
the journey to mercury is six years and
is a rather moment because it takes very
much energy to travel to that planet it
takes as much energy to travel to
mercury as it would take to travel to
put on Pepe colombo should be the most
complete exploratory mission to mercury
ever conceived construction and testing
the probe is well underway at the
european space agency's research and
Technology Center in the Netherlands the
project is a joint mission with the
Japanese and the spacecraft is divided
into two each probe with a specific set
of tasks that the colombo has two
orbiters the one is the European orbiter
called the mercury planetary orbiter and
it has a imaging instruments and
spectrometers but also some instruments
to look at the plasma around mercury
then there is a japanese spacecraft
mercury magnetospheric orbiter that or
will operate at a much higher altitude
in order to to map the magnetosphere and
a plasma
the mission will spend at least a year
investigating the geology interior
structure magnetic field and general
dynamics of mercury
as it does so it will have to deal with
a ferocious heat of the Sun and
reflected radiation from the planet
the probe is equipped with special
thermal shields and a large radiator to
keep the instruments inside that
operating temperature the planetary
orbiter will circle around mercury
keeping always the instrumentation
pointed at the surface
this means that almost all the faces of
the space cross will be exposed to the
high-intensity solar radiation there is
only one side of the spacecraft that we
can call the cold face that carries the
radiator and has to be pointed to the
cold space in order to be able to reject
and radiate all the excessive heat that
the spacecraft that produces
Pepe colombo should reach its
destination by the year twenty
twenty-two not only will it offer a new
insight into mercury but also an idea of
how the other rocky planets of our solar
system were formed
Oh
that in turn could offer new clues about
other worlds circling distant stars
recently a very hot topic on planetary
size or astronomy as external planets
and many of these planets orbits
compared to the run of mercury so very
close to the Sun very close to the
parents top and so some scientists
believe if you studying mercury and
understand the behavior of mercury that
we can also learn something for the
extrasolar planets and understand why
they are formed or are so close to their
parent star planetary scientists a
curious to find out how Mercury's orbit
and rotation may have changed over its
lifetime
that's because many of the distant
planet spotted around other stars appear
to follow similar paths
for macular but we can make analogies
between work around the planetary
systems that we discover the extra solar
systems where we have planets that are
close to their star but with a highly
eccentric orbit and the job except that
these planets are gas giants not like
mercury so the planets themselves are
different but their position is very
similar
what's interesting with Mercury will be
to understand how this interaction works
between the planets and the Sun for a
planet that's very close to it for a
point-and-click what happened to make
sure why is it so dense and how did it
already evolved finding answers to those
questions could help solve other
mistress to
we have a theory to understand how
planetary systems form and the solar
system is a good example
now the theory was based on explaining
the solar system and it was fine
it worked but now when we have
discovered new planets around other
stars in the galaxy the extrasolar
planet they don't fit at all so
something is wrong and the special cases
those that are difficult to understand
in details like mercury are very health
because it is a case where we find a
number of things we don't understand
easily the fleet-footed messenger of
Rome a yet deliver some revealing
insights into how our solar system
formed four-and-a-half billion years ago
history but the only person around it
doesn't have TV coverage of the favor
and find it man you got the black up now
you're gonna be a star in the TV picture
now they'll yes we are getting a TV
picture 1 all
bad way
For more infomation >> Bianca Gascoigne devastated as Jamie O'Hara is evicted from CBB - Duration: 3:29. 
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