this world takes you on a journey a
journey through space and time
I want to tell you the story of an
instrument that has vastly improved our
view of the skies sharpening our
perception of the universe and
penetrating ever deeper toward the
farthest edges of time and space
looking at the night sky we see the
familiar twinkle of starlight like that
has traveled enormous distances to reach
us but we're not seeing the stars
themselves flickr the universe is
gloriously transparent the light from
distant stars and galaxies can travel
unchanged across space for thousands
millions even billions of years
but then in the last few microseconds
before that light reaches our eyes the
accurate view of those stars and
galaxies is snatched away
this is because as light passes through
our atmosphere the ever-changing
blankets of air water vapor and dust
blur the fine cosmic details so for many
years astronomers around the world long
for an observatory in space as early as
1923 the fame German rocket scientist
Hermann Oberth suggested a space-based
telescope
however it would be decades before
technology caught up with the dream the
american astronomer alignment Spitzer
came up with a more realistic plan for a
space telescope in 1946
from a position in space above Earth's
atmosphere a telescope would be able to
detect the pristine light from stars
galaxies and other objects well before
it was distorted by the air we breathe
the result much sharper images than even
the largest telescopes on the ground can
achieve images limited in sharpness only
by the quality of the optics in the
nineteen seventies nasa the national
aeronautics and space administration and
easie the european space agency began
working together to design and build
what would become the Hubble Space
Telescope the name is a tribute to Edwin
Powell Hubble the founder of modern
cosmology who in the nineteen-twenties
prove that not all that we see in the
sky lies within the Milky Way
instead the cosmos extends far far
beyond Hubble's work changed our
perception of mankind's place in the
universe forever and the choice of
naming the most magnificent telescope of
all time after edwin hubble could not
have been more appropriate
it took two decades of dedicated
collaboration between scientists
engineers and contractors from many
countries before Hubble was finally
finished on April the 24th 1995
astronauts aboard the space shuttle
Discovery left on a journey that changed
our vision of the universe forever they
deployed the eagerly-anticipated space
telescope in orbit roughly 600
kilometers above the Earth's surface on
earth the astronomers waited impatiently
for the first results but less than two
months later it was clear that Hubble's
vision was anything but sharp the mirror
had a serious floor engineers have
discovered that the giant telescope has
a warped mirror one of the mirrors in
the Hubble Space Telescope is out of
shape and as a result the pictures it's
sending back and no better than those
from telescopes on the ground
a defect in the shape of the mirror
prevent a double from taking sharp
images the mirrors edge was too flat by
only a mere 50th of the width of a human
hair but to accomplish its mission i
will have to be perfect in every tiny
detail the disappointment was almost too
great to bear not only amongst
astronomers but also for American and
European taxpayers nevertheless over the
following two years scientists and
engineers from NASA and isa work
together to design and build a
corrective optics package named co-star
for corrective optics Space Telescope
axle replacement doubles masters now
faced another tough decision which
science instrument should they removed
so that co-star could be fitted to
Hubble they eventually chose the
high-speed photometer
Hubble's first servicing mission in 1993
has gone down in history as one of the
highlights of human spaceflight it
captured the attention of both
astronomers and the public at large to a
degree that no space shuttle mission
since has achieved meticulously planned
and brilliantly executed the mission
succeeded on all counts co-star
corrected Hubble's eyesight more
perfectly than anyone had dared to hope
when the first images after the
servicing came up on the computer
screens it was instantly clear that the
glass is taken up by the astronauts were
completely correcting Hubble's
nearsightedness Hubble was finally in
business
that was only the first time the Space
Shuttle visited Hubble the telescope was
designed to be upgraded to keep
utilizing you capabilities when more
advanced instruments electrical or
mechanical components became available
they could be installed plus just as
your car needs servicing so Hubble needs
tuning up from time to time engineers
and scientists periodically send the
shuttle to Hubble so that astronauts can
upgrade it using wrenches screwdrivers
and power tools just as your mechanic
does with a car there have been for
servicing mission so far in 1993 97 99
and 2000 to all undertaken by astronauts
transported into space by NASA's Space
Shuttle the next one was supposed to
occur in 2005 it was unfortunately
cancelled in the aftermath of the tragic
columbia crash doubles future is
uncertain
it was originally designed to operate
for 15 years but it's now expected that
its life could be extended to 20 years
Hubble is still producing the most
astonishing results astronomers have
ever known
Hubble's important mission will
eventually come to an end
an unmanned probe will link up with
Hubble in orbit and dock with it when
leaving Hubble the robot will leave
behind a rocket module so that after
some more years of fruitful observing
engineers on the ground can activate
these rockets to control Hubble's final
descent into the atmosphere and to a
peaceful final resting place in the
ocean
however the retirement of the Hubble
Space Telescope will not signal the end
of our and rival view of the universe
rather it will mark a new beginning an
era of even more amazing discoveries and
images from space for Hubble has a
successor the james webb space telescope
is being designed right now and maybe
launched as early as 2011 when that day
comes
scientists using the James Webb Space
Telescope hope to discover and
understand even more about our
fascinating universe
Hubble is an upgradeable space-based
telescope orbiting at almost 600
kilometers placing it well above most of
our image distorting atmosphere it takes
about ninety seven minutes to complete
each orbit it is designed to take
high-resolution images and accurate
spectra by concentrating starlight to
form sharp images that are possible from
the ground with the atmospheric
twinkling of the stars limits the
clarity together as much light as
possible from the faint objects that
observes any telescope needs the largest
Nerak can get despite Hubble's
relatively modest mirror diameter of 2.4
meters
it's well able to compete with
ground-based telescopes having mirrors
that a turn or 20 times larger in
collecting area covers a large satellite
about 16 metres long with the size of a
small bus it's also one of the most
complicated pieces of technology ever
built it contains over 3,000 sensors
that continuously monitor the status of
the hardware so the technicians on the
ground can keep an eye on what's
happening time on Hubble is a precious
commodity astronomers around the world
regularly ask for much more time than is
available keeping Hubble operating 24 7
is no small task not a second must be
lost and all operations from observing
to the so-called housekeeping tasks such
as repositioning the telescope or
uploading new observing schedules are
meticulously planned for astronomers the
most important components of trouble are
its scientific instruments
there are two groups of instruments in
Hubble here and here
the different instruments serve
different purposes some of the making
images some are designed to dissect the
light from the stars and galaxies by
spreading it out form a rainbow like
spectrum
Hubble's unique vantage point in space
makes it capable of observing the
infrared and ultraviolet light but is
otherwise filtered away by the
atmosphere before it can reach
telescopes on the ground
these forms of light revealed properties
of celestial objects that are otherwise
hidden from us some instruments like acs
the advanced camera for surveys are
better for visible and ultraviolet
observations some like Nick mass the
near infrared camera and multi-object
spectrograph
our best for infrared observations
different mechanical and electrical
components keep Hubble functioning the
power for Hubble comes from solar panels
on the side which convert sunlight into
electricity gyroscopes star trackers and
reaction wheels keep Hubble's steady and
pointing in the right direction
not too close to the Sun Moon or earth
as they would destroy the light
sensitive instruments and accurately
towards the objects being studied for
hours or days at a time
Hubble has several communication antenna
on its side that a necessary for sending
observations and other data
down-to-earth double sends its data
first to a satellite in the tracking and
data relay satellite system which then
downlinks the signal to White Sands New
Mexico the observations are sent from
NASA in the United States to Europe
where they are stored in a huge data
archive in Munich
no single nation could undertake such an
enormous project
Hubble has been a major collaboration
between NASA and either the european
space agency from an early stage in its
life
Hubble has been of paramount importance
to European astronomy European
astronomers regularly with more than
fifteen percent of the observing time
with Hubble resulting in several
thousand scientific publications over
the years two groups of European
specialists work with Hubble there are
15 people from either currently working
at the Space Telescope Science Institute
in the USA and 20 others make up the
space telescope European co-ordinating
facility in munich germany
ok
there are no boundaries in space in this
vast universe our closest relatives are
the objects within the solar system we
share the same origin and the same
destiny our solar system was formed
about four and a half billion years ago
from a huge gas cloud
ironically it could have been the deadly
force of a thermonuclear blast from an
exploding star in the vicinity that
triggered our creation the devastating
force of the blast may have disturbed
the precarious equilibrium of the
original gas cloud causing some of the
matter to collapse inwards towards the
center creating a new star our Sun and a
minut percentage of the collapsing
matter became the multi-faceted assembly
of planets that we have around us today
we are in other words just the leftovers
of our son's birth the planets were born
in the rotating disk of dust and gas
left behind as our mother star was
formed the rocky planets formed in the
inner solar system while the enigmatic
gas giants were formed farther out and
then when a fierce wind of smashed atoms
began to blow from the Sun or perhaps
from hot nearby stars or a nearby
supernova only sizable planets could
maintain their gaseous surroundings and
the last wisps of the tenuous cloud
between the planets was whipped away so
in our solar system zoo of celestial
bodies there are rocky worlds
and giant gaseous planets
even now there's no exact estimate of
the amount of matter or even the number
of planets that exist in the solar
system since Pluto's discovery in the
nineteen thirties and its satellite
Gerrans in the nineteen seventies
astronomers have been trying to figure
out if there's anything else out there
beyond the ninth planet in 2003 double
spotted something moving fast enough
across the background of faraway stars
to be an object within the solar system
estimates show that it could be about
the size of a planet and its been named
Sedna after an Internet goddess Sedna
maybe 1,500 kilometers in diameter
that's about three-quarters the size of
Pluto but so far away that it appears
just as a small cluster of pixels even
to Hubble nevertheless it's the largest
object discovered in the solar system
since Pluto the Sun is about 15 billion
kilometers from Sedna 100 times further
than Earth distance from the Sun and
barely gives out as much light and heat
as the full moon so Sedna is engulfed in
an eternal bleak winter center is not
the only mysterious object out there
debris from the formation of the planets
is still floating everywhere in the form
of asteroids and comets of various
shapes and sizes
sometimes their orbits can lead them on
catastrophic courses the Hubble Space
Telescope witness the final journey of
the comet shoemaker-levy 9 it was torn
into numerous pieces by Jupiter's
gravitational Paul when it passed the
massive planet in the summer of nineteen
ninety-two two years later these
fragments returned and drove straight
into the heart of Jupiter's atmosphere
double followed the comet fragments on
their last journey and delivered
stunning high-resolution images of the
impact scars our earth could easily fit
into any of these black bruises
space probes with sophistic
instruments are frequently sent to the
planets of our solar system they provide
close up investigations of these distant
places double 2 provides its own unique
service by opening a window on our solar
system that is never closed
we've gained unprecedented views of
storms on other planets
they're changing seasons
and unprecedented views of other
atmospheric events such as Rory known on
earth as the northern and southern
lights
even though the solar system clearly has
many more surprises in store for us
Hubble has also turned its eye out
towards are the stars looking for
planetary systems astronomers are
beginning their search for life
elsewhere in the universe to start with
they're concentrating on finding
earth-like planets in 2001 Hubble made
the first direct detection of the
atmosphere of an extrasolar planet and
partially determined its composition
measuring the chemical makeup of
extrasolar planetary atmospheres will
one day allow us to search for the
markers of life beyond Earth all living
things breathe and this changes the
composition of the atmosphere in readily
detectable ways astronomers believe
there are many planetary systems similar
to ours orbiting other stars throughout
the galaxy the birth life death and
rebirth of stars continues in an
unending cycle in which stars born of
gas and dust will shine for millions or
billions of years die and return as gas
and dust to form new stars the
byproducts of this continual process
include planets and the chemical
elements that make life possible so
throughout the entire vastness of space
the eternal ebb and flow of life
continues
our son that vital source of energy for
life on Earth is a star a totally
unexceptional star just like billions of
others that we can find throughout the
galaxy
a star is nothing but a sphere of
glowing gas it forms out of a compressed
cloud of gas and releases energy
steadily throughout its life because the
continual chain of nuclear reactions
takes place in its core most stars
combine hydrogen atoms to form helium
through the process called nuclear
fusion the same process that powers a
devastating hydrogen bomb in fact stars
a nuclear factories that convert lighter
elements into heavier elements in a
series of fusion reactions they will
keep blowing until they run out of fuel
and that's it two stars life required
beginning and a steady progress to
sometimes violent end but how can we be
certain of this picture when an
individual star like the Sun outlets
humans by a factor of a few hundred
million to investigate the lifecycle of
a particular organism on earth we don't
have to track an individual specimens
entire life instead we can observe many
of the organisms at once this will show
us all the different phases of its life
cycle for example each stage of a
person's life is a snapshot of the human
experience and so it is with stars
stars live and die of millions or even
billions of years even the most reckless
stars live for at least a million years
longer than the entire history of
humankind and that's why it's extremely
difficult to track age-related changes
in individual stars to learn more about
them we must study different stars every
stage of life and so piece together the
entire cycle from birth to death
Hubble's vivid images have documented
that you mulches birth of stars and
delivered many astonishing images in
colorful detail
the birth of stars in neighboring
stellar maternity wards can be used as a
time machine to replay the events that
created our solar system
Hubble has often had to work hard for
this information because these important
clues about our Genesis lie hidden
behind the veil gently blowing dust Lane
molecular clouds where stars are for
Hubble's ability to observe infrared
light enables it to penetrate the dust
and gas and reveal the newly-born stars
as never before
one of the most exciting of Hubble's
many discoveries was the observation of
dust discs surrounding some newborn
stars very deep inside the Orion Nebula
here we are actually seeing the creation
of new solar systems where planets will
eventually form just as they did in our
own solar system four and a half billion
years ago in the first stages of their
lives stars can stock up on gas from the
original birth cloud material falling
onto the star creates bubbles or even
jets as it's heated and blasted out
along a path that follows the Stars
rotation axis but like the axis through
a wheel
often many stars are born from the same
cloud of gas and dust some may stay
together through the whole lifetime
keeping step as they evolve like
childhood friends that you keep your
life
the stars in a cluster will all have the
same age but we'll have a range of
different masses and this means that
very different destinies await
human existence is the mere blink of an
eye
compared with the life of a star
so the direct observation of a
transition between different stages of
the star's life can only come about by
lucky Charles in 15 highly productive
years Hubble has allowed us to observe
some stars aging in real-time the
telescope has produced starting movies
that allow us to witness how some of
them do modify their appearance over
this minut span of astronomical time the
Stars containing the most mass and their
lives cataclysmically destroying
themselves in Titanic's stellar
explosions known as super novae for a
few glorious months each becomes one of
the brightest objects in the entire
universe outshining all the other stars
in its parent galaxy since its launch in
1990 Hubble has watch the drama unfold
in supernova 1987a the nearest exploding
star in modern times the telescope has
been monitoring a ring of gas
surrounding the supernova glass bubble
has observed the appearance of bright
spots along the ring like gemstones on a
necklace beads cosmic pearls are now
being lit by supersonic shocks unleashed
during the explosion of the star
the ruins of an exploding star can hide
a powerful engine Hubble has probed the
mysterious heart of the Crab Nebula the
tattered remains of an exploding star
vividly described by chinese astronomers
in 1054 and has revealed its dynamics
enter the innermost region of this
nebula I was a special type of star a
pulser like a beacon the star rotates
emitting energy and light in a beam and
it powers the vast nebular of dust and
gas surrounding it
however not all stars and their lives so
violently sun-like stars cool down once
they run out of hydrogen the center
collapses in on itself and the heavier
elements are burned causing the outer
layers to expand and leek slowly into
space at this stage in a star's life
it's called a red giant our son will
become a red giant in a few billion
years at that time it will expand so
much that it will swallow Mercury Venus
and our planet to but these stars are
not finished quite yet they can still
become something quite extraordinary
just before they breathe their last
breath stars like our Sun go out in a
final blaze of glory in its final stages
of nuclear fusion stellar winds blow
from the star causing the red giant to
swell to an enormous size at the heart
of this expansion the exposed heart of
the star floods the gaseous envelope
with powerful ultraviolet light making
it glow because too early telescopic
astronomers these amazing constructions
looked a bit like the newly discovered
planet Uranus they became known as
planetary nebulae
Hubble's keen perception shows that
planetary nebulae are like butterflies
no two are alike
Hubble's dazzling collection of
planetary nebulae show surprisingly
intricate glowing patterns pinwheels
swirlin jets elegant goblet shapes
barrel shapes or even rocket engine
exhausts
from its unique position high above the
distorting atmosphere Hubble is the only
telescope that can observe the swollen
outer envelope of these dying stars in
full detail here we flip back and forth
between Hubble images from 1994 and 2002
one of the greatest mysteries in modern
astrophysics is how a simple spiracle
gasp all such as our Sun can give rise
to these intricate structures for some
planetary nebulae it is as if a cosmic
garden sprinkler created the jets that
stream out in opposite directions
or could these amazing patterns possibly
be sculpted by the magnetic field of a
companion star that funnels the emitted
gas into a jet whatever their cause in
only ten thousand years these fleeting
cosmic flowers disperse in space just as
real flowers fertilize their
surroundings as they decompose the
chemical elements produced inside the
star during its life are dispersed by
the planetary nebula to nourish the
space around providing the raw material
for new generations of stars planets and
possibly even life because they
disappear so quickly on a cosmic time
scale there are never more than about
15,000 planetary nebulae at any one time
in our Milky Way a more lasting monument
to the Dead star is the tiny heart it
leaves behind known as a white dwarf
each of these exceptionally dense
earthside stars are fated to spend the
rest of eternity gradually nicon their
residual heat into space until
eventually in many billions of years
they approach the frigid minus 270
degrees centigrade of space
we live inside a huge star system or
galaxies known as the Milky Way seen
from the outside the Milky Way is a
gigantic spiral consisting of a central
hub embraced by long arms the whole
system slowly rotates between the stars
there are vast amounts of dust and gas
that we can see and some unknown
material called dark matter that remains
invisible to us far from the center out
in one of the spiral arms the suburbs of
the Milky Way is a tiny star system our
home the solar system
when we look up on a clear night we can
see about 5,000 of the closest stars our
eyes struggle to see beyond the thousand
like years because of the dust that
blanket space and demons the distant
starlight so without a telescope we can
only see a minut portion of the entire
100,000 light-years wide milky way for
the Milky Way contains several hundred
billion stars many like our own Sun
although several hundred thousand
million is an almost unfathomable number
it is only the beginning
astronomers believe there are more than
a hundred billion galaxies in the
universe
how many stars would that be
in a handful of sand that can easily be
fifty thousand individual grains our
Milky Way contains so many stars there
can scarcely be enough grains of sand on
a whole beach there are so many galaxy's
containing so many stars in the universe
that we would have to count every grain
of sand on every Beach on the whole
earth in order even to come close to the
right number and then there would be
more stars in the universe
let's take this grain of sand millimeter
across and place it here to represent
the Sun if we would start walking
towards the nearest star it would take
us the best part of the day to get there
we have to travel something like 30
kilometres
so galaxies are mostly large collections
of emptiness if we could squeeze
together all the stars in the milky way
they would easily fit into the volume of
space between our son the nearest stop
in fact to completely fill that volume
we would have to pack in all the stars
from all the galaxies in the entire
universe
when looking at the night sky the
universe seems motionless this is
because our life spans are nothing but
brief drops in the universal ocean of
time in fact the universe is in constant
motion but we would need to what for
vastly longer than a lifetime to
perceive that motion in the night sky
given enough time we would see stars and
galaxies move stars orbit the center of
the Milky Way and galaxies are pulled
together by each other's gravity
sometimes they even collide
Hubble has observed numerous galaxies
crashing together
like majestic ships in the grandest
night galaxies can slip ever closer
until their mutual gravitational
interaction begins to mold them into
intricate figures that are finally and
irreversibly woven together it is an
immense cosmic dance choreographed by
gravity
when two galaxies collide it's not like
a car crash or two billiard balls it in
each other it is more like interlocking
your fingers most of the stars in the
galaxy will pass unharmed through the
collision at worse gravity will fling
them out along with dust and gas to
create long streamers that stretch a
hundred thousand light years or more
the two galaxies trapped in their deadly
gravitational embrace will continue to
orbit each other
ripping out more gas and stars to add to
the tails eventually hundreds of
millions of years from now the two
galaxies will settle into a single
combined galaxy
it is believed that many present-day
galaxies including the Milky Way were
assembled from such a coalescence of
smaller galaxies occurring over billions
of years triggered by the colossal and
violent interaction between the galaxies
stars form from large clouds of gas in
firework bursts creating brilliant blue
star clusters
our own Milky Way is on a collision
course with the nearest large galaxy the
Andromeda galaxy they are approaching
each other at almost 500,000 kilometers
per hour and in three billion years will
collide head off
the direct collision will lead to a
magnificent merger between the two
galaxies during which the Milky Way will
no longer be the spiral galaxy we are
familiar with instead it will evolve
into a huge elliptical galaxy containing
all of its own stars and all of those of
the Andromeda galaxy two seen from the
earth the collision will look something
like this
although this will not happen for a very
long time
there are other dark forces of nature in
play everywhere around us even as we
speak
black holes are the enigmatic villains
of the universe swallow in all that
comes their way allowing nothing to
escape so for astronomers the center of
a black hole is the ultimate unknown no
information can escape from within a
black hole's gravitational stronghold
there is no way to find out what is in
there not even light construct so how do
we know that they are even there
black holes themselves cannot be
observed directly however astronomers
can see the indirect effect of black
holes because the one thing they do
possess in abundance is gravity bubbles
high resolution has revealed the
dramatic distorting effects of black
holes on their surroundings and not just
gravity astronomers find that when
material is packed tightly enough around
a black hole it can ring like a bell
this is the actual note produced by a
black hole some 250 million light-years
from Earth it reverberates through the
disc and has been altered here to fall
within the range of human hearing in
reality it's b-flat some 57 octaves
below middle C astronomers believe that
black holes singularities simple points
in space no volume no extension but
infinitely dense black holes can be
created during the final collapse of a
massive star many times the size of the
Sun the stellar corpses left after the
demise and collapse of a massive star
can be so heavy that no force in nature
can prevent it crumbling under its own
weight into an infinitely small volume
although matter has apparently
disappeared having been compacted into
nothingness it still exerts a powerful
gravitational pull and any stars or
other objects that come to close can be
pulled in
for any black hole there is a point of
no return called the event horizon once
something a nearby star say is pulled in
past this point it will never be seen
again on its way towards the event
horizon the doomstar will begin to
follow a fatal spiraling orbit as the
Star approaches the black hole still
further the matter closest to the hole
feels a greater attraction than the rest
of the star sucking and stretching the
star out towards the hole until the
immense tidal forces pull it to pieces
and devoured
there are quirky or aspects to these
objects to a twisting of space and time
that warts and slows even the passage of
time all objects with a mass deform the
very fabric of space and time but black
holes do this to an extreme degree
according to Einstein's famous theory of
general relativity and intrepid traveler
who could visit a black hole and hang
above the event horizon without being
swallowed would eventually return to
find himself younger than the people he
had left behind
perhaps the most curious objects
astronomers have hypothesized about are
wormholes a wormhole is essentially a
shortcut through space-time from one
point in the universe to another point
in the universe maybe wormholes if they
exist will someday allow travel between
regions in space faster than it would
take light to make the journey through
normal space
I was shown that black holes the most
likely to be present to the center of
all galaxies this one at the center of
our Milky Way a giant supermassive black
hole
perhaps a million times bigger than
those produced by the collapse of a
single massive star it could be the
result of a merger of many stellar-sized
black holes form during the remote
history of our galaxy when two galaxies
collide the black holes at each of their
centers will perform an elaborate dance
long after the two galaxies have merged
into one their central black holes
continue to orbit each other for
hundreds of millions of years before
their final violent murder into a single
weighty black all this final process is
so powerful that it changes the fabric
of space-time enough that we may be able
to observe it from the earth with a new
breed of gravitational wave telescopes
or from special spacecraft in orbit
however compared with the millions of
years it takes four galaxies to merge
the final Cataclysm at the cause would
be relatively brief
so the odds of seen such an event are
small and has recently as 50 years ago
astronomers thought the universe was a
mostly peaceful place for this is far
from the truth
space is often shaken by violent events
cataclysmic explosions of supernovas
collisions of whole galaxies and the
tremendous outpouring of energy
resulting from matter crashing into
black holes he was the discovery of
quasars that gave us the first glimpse
of this turmoil the ground-based
telescopes quasars look like normal
stars and that's exactly what
astronomers first thought they were
naming them quasi-stellar objects but
quasars are in fact much brighter and
further away than stars they can shine
more brightly than a thousand normal
galaxies and a powered by supermassive
black holes stars that orbit to close
are pulled apart draining into the
quasar like water into an enormous
cosmic sink the spiraling gas forms a
thick disk heated to a high temperature
by it's free for motion towards the
black hole the gas blasts its energy
into space above and below the disc in
colossal jets
quasars are found in a wide range of
galaxies many of which are violently
colliding there may be a variety of
mechanisms for igniting quasars
collisions between pairs of galaxies
could trigger the birth of quasars but
Hubble has shown that even apparently
normal and disturbed galaxies Harper
quasars but quasars are not the only
high-energy objects astronomers have
found a serendipitous discovery is
something you make was looking for
something else such events often change
the course of astronomy gamma-ray bursts
were discovered serendipitously in the
late 1960s by US military satellites on
the lookout for Soviet nuclear tests
instead of finding the most devastating
detonations produced by humans some of
the most powerful blasts in the entire
universe were spotted these astoundingly
energetic blasts of gamma rays are
detected at least once per day from
random directions in the sky
although gamma-ray bursts last only a
few seconds the energy they release is
equal to the amount of energy radiated
by our whole Milky Way over a couple of
centuries gamma rays are not visible to
the human eye and special
instrumentation is needed to detect them
for 30 years no one knew what caused
these bursts it was like seeing the
gamma-ray bullet flyby earth without
ever glimpsing the weapon that fired it
together with nearly all other
telescopes in the world Hubble looked
for the smoking gun for many years it
observed the positions in the sky where
gamma ray explosions had been seen
trying to find any object at that
location but all efforts were in vain
until
in 1999 Hubble observations were
fundamental in determining that these
monstrous outburst take place in far
distant galaxies
the cause could be the blast produced in
the final cataclysmic collapse of a
massive star or the dramatic encounter
of two very dense objects such as two
black holes or a black hole and a
neutron star
black holes are certainly some of the
most exotic objects in the universe as
well as affecting matter they can also
show up in some other spectacular ways
because they're enormous gravitational
fields can also reflects light in fact
rays of light that passes close to a
black hole will not follow straight
lines but will be bent into new paths
creating a natural telescope that
compared further into space than ever
thought possible
just as a wandering in the desert season
mirage when light from remote objects is
bent by the warm air hovering just above
the sand we may also see mirages in the
universe the mirages we see with a
modern telescopes such as the Hubble
Space Telescope do not arise from warm
air but instead from remote clusters of
galaxies huge concentrations of matter
long ago
some people thought the earth was flat
this is not surprising since in our
everyday lives
we're not aware of the curvature of our
planet space is actually curved although
we can't see that for ourselves on a
starry night the curvature of space does
however produce phenomena that
astronomers can see one of Albert
Einstein's predictions is that gravity
warp space and therefore distorts rays
of light in the same way that ripples on
a pond create a wart honeycomb pattern
of light on the sandy bottom light from
distant galaxies is distorted and
magnified by the gravitational field of
massive galaxy clusters on its path to
the the effect is like looking through a
giant magnifying glass and the result is
called gravitational lensing
the weird patterns that rays of light
create when they encounter a weighty
object depend on the nature of the
lensing body thus the background object
can appear in several geysers Einstein
rings where the whole image is boosted
and squeezed in a circle of light
multiple images ghostly clones of the
original distant galaxies
or distorted into banana like arcs and
arguments
oh I understand realized in 1915 this
effect would happen in space
he thought it could never be observed
from the earth however in 1919 his
calculations were indeed proved to be
correct
during a solar eclipse expedition to
principal island near the west coast of
Africa led by the renowned british
astronomer arthur eddington the
positions of stars near the obscured
solar disk were observed it was found
that the stars have moved a small but
measurable distance outwards on the sky
compared with when the Sun was not in
the vicinity
nowadays faint gravitational images of
objects in the distant universe are
observed with the best telescopes on
earth and of course with the sharp cited
Hubble
Hubble was the first telescope to
resolve details within the multiple arcs
revealing the form and internal
structure of the lens to background
objects directly
in 2003 astronomers deduce that a
mysterious Ark of light from one of
Hubble's images was the biggest
brightest and hottest star forming
region ever seen in space
it takes very massive objects for
example clusters of galaxies to make
space curve so much that the effect
becomes visible in deep images of the
distant universe even with Hubble's
astonishing resolution and so far
gravitational lenses have been observed
mainly around clusters of galaxies which
are collections of hundreds or thousands
of galaxies and I thought to be the
largest gravitationally bound structures
in the universe astronomers know that
the matter we see in the universe is
just a tiny percentage of the total mass
that must be there for matter exerts a
gravitational force and the visible
stuff is simply not enough to hold
galaxies and clusters of galaxies
together since the amount of warping of
the banana shaped images depends on the
total mass of the lens gravitational
benzene can be used to weigh clusters
and to understand the distribution of
the hidden dark matter
on clear images from Hubble one can
usually associate the different arcs
coming from the same background galaxy
by this process allows astronomers to
study the details of galaxies in the
young universe and too far away to be
seen normally with the present
technology and telescopes
a gravitational lens can even act as a
kind of natural telescope in 2004 Hubble
was able to detect the most distant
galaxies in the known universe using the
magnification from just such a
gravitational lens in space
like my travel through a vacuum at the
higher-speed anything can ever reach but
it's still a finite speed
this means that it takes awhile for like
raised to travel between two points in
space the speed of light in space is
about 300,000 km/s now 300,000
kilometres is nearly the distance from
the earth to the moon and so it takes
just over a second for light to travel
from the moon to the earth so when we
look at the moon we're seeing it as it
was just over a second ago who haven't
thought about what it would be like to
travel in time the finite speed of light
enables us to get close by allowing us
to look back in time when looking out
into space we just need to wait for the
light from distant places to reach ups
and it shows how things were when the
light began its journey powerful
instruments like Hubble have made it
possible to look farther out and farther
back than ever before
what cosmologists are seeing is simply
astounding in the nineteen-twenties
astronomer Edwin Hubble discovered that
most galaxies appear to be moving away
from us at a rate proportional to their
distance
the further away galaxy is the faster it
appears to be moving away from this this
is due to the expansion of the universe
that expansion began in a Titanic
explosion called the Big Bang many
billions of years ago the rate of
expansion holds the key to estimating
the agent size of the universe this rate
is called the Hubble constant the agent
size of the universe can be estimated by
running the expansion backwards until
everything is compressed into that
infinitely small point of energy from
which the universe was generated the
top-ranked scientific justification for
building Hubble was to determine the
size and age of the universe the quest
to determine the Hubble constant
precisely was headed by the key project
team a group of astronomers who used
Hubble to look for remote accurate
milepost markers a special class of
stars called Cepheid variables
cepheid's have very stable and
predictable brightness variations the
period of these variations depends
strictly on the physical properties of
the star which can be used to determine
their distance very effectively for this
reason these stars are better known as
standard candles the cepheid's have been
used as reliable stepping stones to make
distance measurements for super novae
which are much brighter than cepheid's
and so can be seen at far greater
distances problems measured the light
from supernova explosions more
accurately than any other instrument
mostly due to its high resolution from
the ground the image of a supernova
generally blends in with the image of
its host galaxies Hubble can clearly
distinguish the light from the two
sources selfies and super novae have
given a measure of the scale of the
universe today we know the age of the
universe too much higher position than
ever before around 14 billion years
for many years astronomers have
discussed whether the expansion of the
universe would stop in some distant
future making the universe collapse in a
fiery big crunch or whether it would
continue to expand ever more slowly
combined observations of distant
supernovae with Hubble and most of the
world's top class telescopes we used to
measure distances to remote super novae
and it looks like the expansion of our
universe is nowhere near slowing down
instead it seems to be speeding up
when Hubble was used to measure how the
expansion of the universe has changed
with time it turned out quite
surprisingly that during the first half
of cosmic history the expansion rate was
actually slowing down then a mysterious
force a sort of anti-gravity made the
universe hit the gas pedal starting the
acceleration we see today
this suggests an extraordinary fate for
the universe because it implies that the
anti gravity force is getting stronger
all the time if this continues it will
eventually overwhelm all gravity and
catapult the universe into a super fast
acceleration that will shred everything
into its constituent atoms cosmologists
have called this nightmare scenario that
big rip
we are collecting unexpected news from
deep space just as geologists dig deeper
underground to find ever more ancient
fossils bearing witness to ever more
remote epochs so astronomers excavate
deeper and deeper two wards the
beginning of time by looking for light
coming from fainter and thus more
distant objects bubbles started a new
era we could call Astro archaeology and
it began during Christmas 1995 pointing
the world's most sophisticated telescope
at the same piece of sky for 10 days in
a row may sound a bit strange and this
was what many astronauts thought when
they tried it for the first time at the
end of 1995
deep field observations are long-lasting
exposures pointing at a particular
region of the sky they aim to reveal
faint objects by collecting as much
light as possible over a long period of
time the deeper and observation goes the
fainter of the objects that become
visible objects in the sky can appear
fate either because their intrinsic
brightness is low or because their
distance is great when this experiment
was first proposed an experiment
consistent staring at the same patch of
the sky for weeks
nobody really knew where they would have
liked to see interesting scientific
results when we first saw the images
result was astonishing
we could see more than three thousand
galaxies in this small field the
observed region of sky in as a major the
Big Dipper was carefully selected to be
as empty as possible so that Hubble
would look far beyond the start of our
own Milky Way and out past nearby
galaxies the thousands of galaxies
observed in the first deep field where
at various stages of evolution and was
strung out along the corridor of
billions of light-years this allowed
astronomers to study the evolution of
these objects to time you've seen
different galaxies at different stages
of their lives
after the first deep field another long
exposure was taken in the southern sky
together the hubble deep field north and
south gave astronomers Pete portals to
the ancient universe for the first time
some of the objects viewed on the images
was so dim but seeing them would be as
difficult as discerning a flashlight on
the movement from Earth and we could
definitely tell that the Hubble Deep
Field has opened a new era in up to
inflationary cosmology transforming our
view of the distant universe the hubble
deep field of course the real revolution
and modern astronomy after the first
deep field almost all ground and
space-based telescopes were pointed at
the same area for long periods some of
the most interesting results in
astronomy have emerged from this
fruitful synergy between instruments of
different sizes in different
environments and with sensitivity to
different wavelengths they gave us the
first clear picture of the
star-formation history throughout the
universe
astonishingly they showed that star
formation peaked within the first few
billion years of the universe's creation
at that time starts forming over 10
times the rate they are today
once they had begun to discover the most
distant universe ever seen Hubble
astronomers try to push their
observations even farther back in time
in 2003 and 2004 Hubble performed its
deepest exposure ever the Hubble Ultra
Deep Field it is a 28-day longexposure
going much deeper than the earlier
Hubble Deep Field north and south the
Hubble Ultra Deep Field reveals the
first galaxies to emerge from the
so-called Dark Ages the time shortly
after the Big Bang when the first stars
reheated the cold dark universe just
after the Big Bang in the newborn fast
expanding universe before the era of the
stars and galaxies the distribution of
matter was fairly smooth as time went on
the king of all forces gravity started
acting slowly but steadily
under the influence of gravity from the
mysterious Dark Matter small clumps of
normal matter started to coalesce in
regions where the density was slightly
higher than average with no start to
light up space the universe was in its
dark age where the density of the clumps
became higher even more matter was
attracted and a competition between the
expansion of space and gravity took
place where gravity one regions stopped
expanding and started to collapse in on
themselves the first stars and galaxies
were born
where the matter density was highest at
the intersections between the large
web-like structures of matter the
largest structures we know were formed
clusters of galaxies
the Deep Field images are studied with a
wide range of galaxies of various sizes
shapes and colors astronomers will spend
years studying the myriad shapes of the
galaxies in this image to understand how
they formed and have evolved since the
Big Bang in vibrant contrast to the
images rich harvest of classic spiral
and elliptical galaxies there is also a
zoo oddball galaxies littering the field
some look like toothpicks others like
links on a bracelet a few appear to be
interacting with each other they're
strange shapes are a far cry from the
majestic spiral and elliptical galaxies
we see today these oddball galaxies
Chronicle a period when the universe was
more chaotic when order and structure
were just beginning to emerge one of the
great things about Hubble is that there
are many instruments on board that can
make different observations at the same
time the Hubble Ultra Deep Field is
actually two separate images taken by
two instruments doubles acs camera and
the thickness instrument Nick Marcy's
even further than the acs it detects
infrared light and so it's able to
reveal the farthest galaxies oversee
because the expanding universe is
stretched and weaken the light from
these objects so much that they're now
only visible at infrared wavelengths the
Hubble Ultra Deep Field is likely to
remain the deepest image of the universe
for the next decade or so until an
easier arianne rocket launches the james
webb space telescope in 2011
up until today during the first 15 years
of its life Hubble has orbited the earth
80,000 times this is the same as
three-and-a-half billion kilometers or
24 times the distance from the earth to
the Sun Hubble has taken more than
500,000 exposures of the universe and
created a visual heritage that has
shaped the way humanity looks at the
universe today
but Hubble's perhaps greatest legacy has
been to open our eyes to the incredible
beauty of nature not only out there in
the depths of cosmos but also everywhere
around us in our daily lives and it's
nowhere finished yet
For more infomation >> Origami pyramid is a Polyhedron out of paper - Duration: 1:50. 
For more infomation >> Watch D.R.A.M. on YouTube
For more infomation >> [ENG SUB] TAEYEON 태연 I Got Love Music Video Teaser #2 - Duration: 0:23. 
For more infomation >> Hyundai Accent 1.4i Dynamic - Duration: 1:15. 
For more infomation >> Hyundai Atos 1.1i Dynamic - Duration: 1:09. 
For more infomation >> Toyota Aygo 1.0 VVT-i 5-drs NOW Airco - Duration: 1:15. 
For more infomation >> Nowe Seriale i Odcinki ... Wiosna 2017 w TVP1 - Zwiastun - Duration: 2:23. 
For more infomation >> Hyundai ix35 2.0i i-Catcher RIJKLAAR / NAVI / CLIMATE / TREKHAAK - Duration: 1:15. 
For more infomation >> Hyundai ix35 2.0I DYNAMIC trekh/zomer+winterset 16" - Duration: 1:01. 
For more infomation >> Plastic in new cars attracting rats - Duration: 3:59. 
For more infomation >> Síntomas, Causas y tratamientos de la Próstata Agrandada(aumentada) o hiperplasia prostática benigna - Duration: 5:57. 
For more infomation >> Horizon Zero Dawn (PS4) - Trailer - Explore a Região Selvagem - LEGENDADO PT-BR - Duration: 1:01. 
No comments:
Post a Comment