by taking our sense of sight far beyond
the realm of our forebears imagination
these wonderful instruments the
telescope's open the way to a deeper and
more perfect understanding of nature
for millennia mankind gazed out into the
mesmerizing night sky without
recognizing the stars of our own Milky
Way galaxy as other sons all the
billions of sister galaxies making up
the rest of our universe
or that we are merely punctuation in the
universe is 13.7 billion year long story
with only our eyes as observing tools we
had no means of finding solar systems
around other stars or of determining
whether life exists elsewhere in the
universe
today we're well on our way to
unraveling many of the mysteries of the
universe living in what may be the most
remarkable age of astronomical discovery
i'm dr. jay and i will be your guide to
the telescope that amazing instrument
that proved to be mankind's gateway to
the universe
for centuries ago in 1609 a man walked
out into the fields near his home he
pointed his homemade telescope at the
moon the planets and the stars
his name was Galileo Galilei
astronomy would never be the same again
today 400 years after galileo first
pointed a telescope to the skies
astronomers use giant mirrors on remote
mountaintops to survey the heavens
telescopes collect faint chirps and
whispers from outer space scientists
have even launched telescopes into Earth
orbit high above the disturbing effects
of our atmosphere
and you has been breathtaking
however Gallio did not in fact invented
the telescope that credit goes to hunt
slipper hey slightly obscure Dutch
German spectacle maker but i'm flipping
hey never use this telescope to look at
the stars instead he thought his new
invention would may benefit seafarers
and soldiers little hey came from
middleburg then a large trading City in
the fledgling dutch republic
in 1608 that they found that when
viewing a distant object through a
convex and concave lens the object would
be magnified if the two lenses were
placed at just the right distance from
one another
the telescope was born
in September 1608 with a revealed his
new invention to prince maurice of the
Netherlands he could not have chosen a
more advantageous moment because at that
time the Netherlands were embroiled in
the eighty years war with Spain
the new spyglass could magnify objects
and so it could reveal enemy ships and
troops that were too distant to be seen
by the unaided eye a very useful
invention indeed but the Dutch
government never granted little hey
Peyton for his telescope the reason was
that other merchants also claimed the
invention especially for his competitor
sorry as Johnson the dispute was never
resolved and to this day the true
origins of the telescope remain shrouded
in mystery Italian astronomer galileo
galilei the father of modern physics
heard about the telescope and decided to
build his own
about 10 months ago I report to reach my
ears that the certain flamming had
constructed the spyglass by means of
which visible objects so very distance
from the eye of the observer wear this
think we seen as if nearby
Galileo was the greatest scientists of
his time he was also a strong supporter
of the new worldview advocated by the
Polish astronomer Nicolaus Copernicus
who proposed that the earth orbiting the
Sun instead of the other way around
based on what he had heard of the dutch
telescope Galileo constructed his own
instruments they were of much better
quality
finally sparing neither labor no
expenses that i succeeded in
constructing for myself so excellent an
instrument that object seen by means of
it appeared nearly 1,000 times larger
than when regarded without natural
vision
it was time to train the telescope on
the heavens
I have been led to the opinion and
conviction that the surface of the moon
is not smooth uniform and precisely
spherical as a great number of
philosophers believe it to be but he's
an even graph and full of cavities and
prominence ease being nothing like the
face of the earth
a landscape of craters mountains and
valleys the world like our own a few
weeks later in january 1610 Kelly looked
at Jupiter close to the planet he saw
for prix of light that changed their
position on the sky
night after night along with Jupiter it
was like a slow cosmic ballet of
satellites orbiting the planet these
four prix of light would come to be
known as the Galilean moons of jupiter
what else did Galileo discover the
phases of Venus just like the moon venus
waxes and wanes from Crescent too full
and back again strange appendages on
either side of Saturn dark spots on the
face of the Son and of course starts
thousands of them maybe even millions
each too faint to be seen by the naked
eye it was as if mankind had suddenly
thrown off its blindfold there was a
whole universe to discover out there
news about the telescope spread across
Europe like wildfire in Prague at the
court of Emperor Rudolph the second
Johannes Kepler improved the design of
the instrument in Antwerp Dutch
cartographer Michelle Phan language and
produced the first reliable maps of the
Moon showing what he believed to be
continents and oceans and johannes
hevelius a wealthy brewer in Poland
built huge telescopes at his observatory
and dancing this Observatory was so
large that it covered three rooftops but
the best instruments of the time were
probably constructed by christian
curtains in the netherlands in 1655
Puritans discovered Titan the largest
moon of Saturn a few years later his
observations revealed Saturn's ring
system something Galileo had never
understood and last but not least hoods
saw dark markings and bright polar caps
on Mars could there be life on this
remote alien world the question occupies
astronomers to this day the earliest
telescopes will refracting telescopes
that used lenses to collect and bring
together the Starlight later the lenses
were replaced with mirrors this
reflecting telescope was first built
barnacles ookie and later refined by
Isaac Newton now in the late 18th
century the largest mirrors in the world
were cast by william herschel an
organist turned astronomer who worked
with his sister Caroline
in the house in bath in England the
Herschel's poured red-hot molten metal
into a mold and when the whole thing had
cooled off they would polish the surface
so that it would reflect starlight
during the course of his life special
built more than 400 telescopes
the largest of these was so huge that he
needed for servants to operate all the
various ropes wheels and pulleys that
were required to track the motions of
the stars across the night sky which is
of course course by the Earth's rotation
now her she was like a surveyor he
scanned the heavens and catalogued
hundreds of new nebulae and binary stars
he also discovered that the Milky Way
must be a flat disk and even measured
the motion of the solar system through
that disk by observing the relative
motions of the stars and the planets and
then on the thirteenth of march in 1781
he discovered a new planet Uranus it was
over 200 years until masses voyager 2
spacecraft gave astronomers their first
close-up look of this distant world in
the lush and fertile country side of
central island William Parsons the third
Earl of Ross built the largest telescope
of the 19th century with a metal mirror
a whopping 1.8 meters across the giant
telescope became known as the Leviathan
off parsons town on occasional clear
moonless nights the Earl's sat at the IP
and sailed on a journey through the
universe
to the Orion Nebula now known to be a
stellar nursery onto the mysterious Crab
Nebula the remnant of a supernova
explosion whirlpool nebula Lord Ross was
the first to note its majestic spiral
shape a galaxy like our own with
intricate clouds of dark dust and
glowing gas billions of individual stars
and who knows maybe even planets like
Earth
the telescope had become our vessel to
explore the universe
at night your eyes at that to the dark
your pupils widen to let more light into
your eyes as a result you can see dimmer
objects and fainter stars now imagine
you had pupils 1-meter cross you look
pretty strange but you'd also have
supernatural eyesight and that's what
telescopes do for you
a telescope is like a funnel
its main lens or mirror collect the
starlight and brings it all together
into your eye
the bigger the lens or the mirror of a
telescope the faint of the objects you
can see so sighs really is everything
but how big can you make a telescope
well actually not too big if it's a
retractor the starlight has to pass
through the main length and so you can
only support it around the edge now she
make the lens too big it becomes too
heavy and it starts deforming under its
own weight
that means that the image will be
distorted the largest refractor in
history was completed in 1897 at York's
observer outside Chicago
its main lens was just over one meter
across but it's too was an incredible 18
metres long with the completion of the
Yerkes telescope the builders of
refracting telescopes have pretty much
reached a limit you want bigger
telescopes think mirrors in a reflecting
telescope the star light bounces off the
mirror instead of passing through a
length that means that you can make the
mirror a lot thinner than a lens and you
can support it from the back
the result is that you can build a lot
larger mirrors and lenses big mirrors
came to Southern California a century
ago
back then mount wilson was a remote peak
in the wilderness of the San Gabriel
Mountains the sky was clear and the
nights were dark
here George Ellery Hale first built a
1.5 meter telescope smaller than Lord
Ross's retired Leviathan it was a much
better quality and at a much better site
to hail talk local businessman John
hooker into financing a 2.5 meter
instrument terms of glass and riveted
steel will hold up Mount Wilson the
hooker telescope was completed in 1970
it would remain the largest telescope in
the world for 30 years a big piece of
cosmic artillery ready to attack the
universe and attack it did along with
incredible size of the new telescope
came transformations in the way the
image was viewed astronomers no longer
peered through the eyepiece of the new
giant but instead collected the light on
photographic plates for hours on end
never before had anyone period so far
into the cosmos spiral nebulae turn out
to be brimming with individual stars
could they be sprawling stellar systems
like our own Milky Way and Andromeda
nebula edwin hubble discovered a
particular type of star that changes its
brightness with clock like precision
from his observations how was able to
reduce the distance to Andromeda almost
a million light-years spiral nebulae
like Andromeda
we're clearly individual galaxies in
their own right but that wasn't the only
incredible thing most of these galaxies
were found to be moving away from the
Milky Way at Mount Wilson double
discovered that the nearby galaxies are
receding at small velocities whereas the
distant galaxies are moving away at a
much faster pace the conclusion the
universe was expanding the hotel scope
at giving scientists the most profound
astronomical discovery of the 20th
century thanks to the telescope we have
traced the history of the universe a
little less than 14 billion years ago
the universe was born in a huge
explosion of time and space matter and
energy called the Big Bang tiny quantum
ripples grew into dense patches in the
primordial brew from these galaxies
condensed a stunning variety of sizes
and shapes
nuclear fusion in the cause of stars
produce new Adams carbon oxygen iron
gold
supernova explosions blew these heavy
elements back into space raw material
for the formation of new stars and
planets
someday somewhere somehow simple organic
molecules evolved into living organisms
life is one miracle in an ever-evolving
universe we are Stardust it's a grand
vision and a sweeping story brought to
us through telescopic observations
imagine without the telescope we would
know about just six planets one moon and
a few thousand stars astronomy would
still be in its infancy like buried
treasures the outpost of the universe
have back into the adventurous from
immemorial times princesses and
potentates political or industrial
equally with men of science have felt
the lure of the Uncharted Seas of space
and through their provision of
instrumental means the sphere of
exploration has rapidly widened
George Ellery Hale had one final dream
to build a telescope twice as large as
the previous record-holder meet the
grand old lady of twentieth-century
astronomy a five-metre Hale telescope at
Palomar Mountain over 500 tons of moving
weight yet so precisely balanced that it
moves gracefully as a ballerina
it's 40-ton mirror reveal stars 40
million times fainter than the eye can
see completed in 1948 the Hale telescope
gave us unsurpassed views of planets
star clusters nebulae and galaxies
giant Jupiter with its many moons the
stunning flame nebula
Faye twists of gas in the Orion Nebula
but could we go bigger still
well socket astronomers tried in the
late nineteen seventies I up in the
caucasus mountains they both the bolshoy
telescope as a mutiny sporting a primary
mirror six meters in diameter but it
never really lived up to its
expectations
it was simply too big too expensive and
too difficult so did telescope builders
have to give up at that point they have
to bury their dreams of even bigger
instruments at the history of the
telescope come to a premature end
well of course not today we have 10
meter telescopes in operation and even
bigger ones are on the drawing board
what was the solution new technologies
just as modern cars don't look like a
model t ford anymore so our present-day
telescopes radically different from the
classic predecessors like the 5-meter
Hale telescope for one thing the amounts
are much smaller the old-style mount is
an equatorial one where one of the axes
is always mounted parallel to the
Earth's rotation axis in order to keep
track of the skies motion the telescope
simply has to rotate around this axis at
the same speed with which the Earth
rotates easy but space hungry the
modern-day altitude as mount a much more
compact with amount like that the
telescope is pointed much like a cannon
one simply chooses the bearing choose
the altitude and off you go
the problem is to keep track of the
skies motion the telescope pretty much
has to rotate around both axes and at
varying speeds essentially this only
became possible once telescopes were
computer-controlled a small amount is
cheaper to build moreover it fits into a
smaller dome which reduces the costs
even further and it improves the image
quality take the twin keck telescopes on
the why for example although their
10-meter mirrors are twice as large as
the one of the Hale telescope they
nevertheless fit into smaller domes and
the one on palomar mountain
telescope mirrors have evolved to they
used to be thick and heavy now they're
thin and lightweight mirror shells that
can be many meters wide are cast in
giant rotating ovens and they are still
less than 20 centimeters thick an
intricate support structure prevents the
thin mirror from cracking under its own
weight computer-controlled pistons and
actuators also help to keep the mirror
in perfect shape this system is called
active optics the idea is to compensate
and to correct any deformations of the
main mirror caused by gravity the wind
or temperature changes now within mirror
also ways much less that means that its
whole supporting structure including the
amount can also be a lot trimmer and
lighter and cheaper now here's the 3.6
meter new technology telescope built by
European astronomers in the late
nineteen eighties it served as a testbed
for many of the new technologies and
telescope building and even its
enclosure has nothing in common with
traditional telescope domes the new
technology telescope was a great success
it was time to break the six meter
barrier monarchia observatories sits on
the highest point in the Pacific 4200
meters above sea level
on the beaches of Hawaii tourists enjoy
the Sun and the surface but high above
them
astronomers face chilling temperatures
and altitude sickness in their quest to
unravel the mysteries of the universe
the keck telescopes are among the
largest in the world that mirrors are 10
meters across and wafer-thin tiled like
a bathroom floor they consist of 36
hexagonal segments each control to
nanometer precision these are true
Giants devoted to observing the heavens
the cathedrals of science night for
Mountain keya the cat telescopes begin
collecting photons from the far reaches
of the cosmos that when mirrors
combining to be effectively larger than
all earlier telescopes what will be
tonight's catch
a pair of colliding galaxies billions of
light-years away a dying star gasping
its last breath into a planetary nebula
or maybe an extrasolar planet that might
Harbor life
on cerro paranal in the Chilean Atacama
Desert the driest place on earth we find
by far the biggest astronomy machine
ever built the European very large
telescope
the VLT is really for telescopes in one
each sporting an 8.2 me to mirror and
two career
Mellie part yet one native mapuche names
for the Sun the Moon the Southern Cross
and Venus huge mirrors were cast in
Germany polished in France ship to Chile
and then slowly transported across the
desert at sunset the telescope
enclosures open up
star light rains down on the VLT merits
new discoveries are made a laser pieces
the night sky the projecting artificial
star into the atmosphere 90 kilometers
above our heads away from sensors
measure how the Styles image is
distorted by the atmospheric turbulence
then fast computers tell a flexible
mirror of how it has to deform itself in
order to correct the distortion in
effect
I'm twinkling the stars this is called
adaptive optics and it's the big magic
trick of present-day astronomy without
it our view of the universe would look
blood by the atmosphere but with it our
images are razor-sharp the other piece
of optical wizardry is known as
interferometry the ideas to take the
light from two separate telescopes and
to bring it together in a single point
for preserving the relative shifts
between the light waves if it is done
precisely no result is that the two
telescopes act as if they were part of a
single colossal mirror as large as the
distance between them in effect
interferometry use your telescope eagle
like vision it allows smaller telescopes
to review the level of detail that would
otherwise only be visible with a much
darker telescope between keck telescopes
on Mauna Kea regularly team up as an
interferometer in the case of the realty
or four telescopes can work together in
addition several smaller auxiliary
telescopes can also join the ranks in
order to sharpen up the view even more
other big telescopes can be found all
over the globe subaru and Gemini North
on mountain archaea Gemini's south and
the Magellan telescopes in Chile the
large binocular telescope in Arizona
they are constructed at the best
available sites high and dry clear and
dark their eyes are as large as swimming
pools all kitted out with adaptive
optics to counteract the blurring
effects of the atmosphere and sometimes
they can have the resolution of a
virtual betterment thanks to
interferometry
actual sizes and school
shapes of some stars a cool planet
orbiting a brown dwarf giant stars
whirling around the core of our Milky
Way galaxy governed by the gravity of a
supermassive black hole we've come quite
away since Galileo's day
five years ago when Galileo Galilei we
wanted to show others what he saw
through his telescope he had to make
drawings
the pockmarked face of the moon
the dance of the Jovian satellite
sunspots all the stars in Orion he took
his drawings & publish them in a small
book the starry messenger that was the
only way you could share his discoveries
with others for well over two centuries
astronomers also had to be artists
viewing through there I pieces in a
detailed drawings of what they saw the
stark landscape of the Moon a storm in
the atmosphere of Jupiter the subtle
view of gas in it is nebulae and
sometimes they all were interpreted what
they saw dark linear features on the
surface of Mars were thought to be canal
suggesting civilized life on the surface
of the red planet we now know that the
canals were an optical illusion
what astronomers really needed was an
objective way to record the light
collected by the telescope's without the
information first having to pass through
their brains and they're drawing pads
photography came to the rescue
the first the karyotype of the moon was
made in 1840 by Henry Draper photography
was less than 15 years old but
astronomers have already seized on its
revolutionary possibilities so how did
photography work well the sensitive
emulsion on a photographic plate
contained small grains of silver halide
expose them to light and they turned
dark
the result was negative image of the sky
with dark stars on a light background
but the real bonus was that the
photographic plate can be exposed for
hours on end when you take in the night
sky with your own eyes once they're dark
adapted you don't see more and more
stars just by looking longer but with a
photographic plate you can do just that
you can collect and add up the light
over ours are men so a longer exposure
reveals more and more stars
and more and more and then some in the
nineteen fifties Schmidt telescope at
the palomar observatory was used to
photograph the entire northern sky
almost 2,000 photographic plates each
exposed for nearly an hour a treasure
trove of discovery photography had
turned observational astronomy into a
true science objective measurable and
reproducible but Silva was slow
you have to be patient the digital
revolution changed all that silicon
replace silver pixels replace grains
even in consumer cameras we no longer
use photographic film instead images are
recorded on a light-sensitive chip a
charge-coupled device or CCD short
professional see cds are extremely
efficient and to make them even more
sensitive they are cooled down to well
below freezing using liquid nitrogen
almost every photon is registered as a
result exposure times can be much
shorter
what the palomar observatory Sky Survey
achieved in an hour
accd can now do in a few short minutes
using a smaller telescope the silicon
revolution is far from over
astronomers have built huge ccd cameras
with hundreds of millions of pixels and
more to come
the big advantage of digital images is
that they're well digital they're all
set and ready to be worked on with
computers astronomers use specialized
software to process their observations
of the sky stretching or contrast
enhancing reveals the faintest features
of navy or galaxies color-coding
enhances and brings out the structures
that would otherwise be difficult to see
moreover by combining multiple images of
the same object that were taken through
different color filters one can produce
spectacular composites that blur the
boundary between science and art you too
can benefit from digital astronomy has
never been so easy to dig up and enjoy
the amazing images of the cosmos
pictures of the universe are always just
a mouse click away
robotic telescopes equipped with
sensitive electronic detectors are
keeping watch over the sky right now the
sloan telescope in New Mexico has
photographed and cataloged over a
hundred million celestial objects
measure distances to a million galaxies
and discovered a hundred thousand new
quasars
but one survey is not enough the
universe is an ever-changing place i see
comments come and go
leaving scattered debris in their way
asteroid zip by
distant planets orbit their mother stars
temporarily blocking part of the star's
light supernovas explode while elsewhere
new stars are born
pulsars flash gamma-ray bursts detonate
black hole secrete
to keep track of these grand plays of
nature astronomers want to carry out all
sky surveys every year or every month or
twice a week at least that's the
ambitious goal of the large synoptic
survey telescope if completed in 2015
it's three gigapixel camera will open up
a webcam window on the universe more
than fulfilling astronomers dreams this
reflecting telescope will photograph
almost the entire sky every three nights
when you listen to your favorite piece
of music your ears pick up on a very
wide range of frequencies from the
deepest rumblings of the base to the
very highest pitch vibrations
now imagine your ears were only
sensitive to a very limited range of
frequencies this out and most of the
good stuff but that's essentially the
situations that astronomers are in our
eyes only sensitive to a very narrow
range of light frequencies visible light
but we are completely blind to all other
forms of electromagnetic radiation
however there are many objects in the
universe that do emit radiation at other
parts of the electromagnetic spectrum
for example in the nineteen thirties it
was discovered by accident that there
are radio waves coming from the depths
of space some of these ways have the
same frequency as your favorite radio
station but there are much weaker and of
course there's nothing to listen to in
order to tune into the radio universe
you need some sort of receiver radio
telescope fall but the longest
wavelength a radio telescope is just a
dish much like the main mirror of an
optical telescope but because radio
waves are so much longer than visible
light ways the surface of a dish doesn't
have to be nearly as smooth as the
surface of a mirror and that's the
reason why it's so much easier to build
a large radio-telescope than it is to
build a large optical telescope also at
radio wavelengths it is much easier to
do interferometry that is to increase
the level of detail that can be seen by
combining the light from two separate
telescopes as if they were part of a
single giant dish
The Very Large Array in New Mexico for
example consists of 27 separate antennas
each measuring 25 meters across
now each antenna can be moved around
individually and in its most extended
configuration the virtual dish mimicked
by the array measures 36 kilometres
across
so what does the universe look like in
the radio
well four star our Sun shines very
brightly at radio wavelengths so does
the center of our Milky Way galaxy but
there's more fossils are very dense
stellar corpses that emit radio waves
only into a very narrow beam in addition
they rotate at speeds of up to several
hundred revolutions per second so in
effect apostle looks like a rotating
radial lighthouse and what we see from
them is a very regular and fast sequence
of very short radio pulses and the name
the radio source known as Cassiopeia A
is in fact the remnant of a supernova
that exploded in the 17th century
Centaurus A Cygnus a and Virg away are
all giant galaxies that poor a huge
amounts of radio waves each galaxy is
powered by a massive black hole at its
center some of these radio galaxies and
quasars are so powerful that their
signals can still be detected from a
distance of ten billion light-years and
then there's the faint relatively short
wavelength radio hits that fills the
entire universe
this is known as the cosmic microwave
background and it is the echo of the Big
back the very afterglow of the hot
beginnings of the universe
each and every part of the spectrum has
his own story to tell at millimetre and
submillimetre wavelengths astronomers
study the formation of galaxies in the
early universe and the origin of stars
and planets in our own Milky Way but
most of this radiation is blocked by
water vapor in our atmosphere to observe
it you need to go high and dry to land a
chat or for example at five kilometers
above sea level this surrealistic
plateau in more than chili is the
construction site of Alma the Atacama
Large millimeter/submillimeter in 2014
Alma will be the largest astronomical
observatory ever built
64 and tenants each weighing 100 tons
will work in unison giant trucks will
spread them out over an area as large as
London to increase the detail of the
image or bring them close together to
provide a wider view each move will be
made with millimeter precision many
objects in the universe also glow in the
infrared discovered by William Herschel
infrared radiation is often also called
heat radiation because it is emitted by
all relatively warm objects including
humans
you may be more familiar with infrared
radiation than you think because on
earth this kind of radiation is used by
night vision goggles and cameras but to
detect the faint infrared glow from
distant objects astronomers need very
sensitive detectors cool down to just a
few degrees above absolute zero in order
to suppress their own heat radiation
today mostly optical telescopes are also
equipped with infrared cameras they
allow you to see right thru a cosmic
dust cloud revealing the newborn stars
inside something that just cannot be
seen in the optical for example take
this optical image of the famous stellar
nursery in Orion but look how different
it is when seen through the eyes of an
infrared camera being able to see
infrared is also very helpful when
studying the most distant galaxies the
newborn stars in a young galaxies shine
very brightly in the ultraviolet but
then this ultraviolet light has to
travel for billions of years across the
expanding universe the expansion
stretches the light ways so that when
they are received by us they've been
shifted all the way into the
near-infrared this stylish instrument is
the magic telescope on La Palma it
searches the sky for cosmic gamma rays
the most energetic form of radiation in
nature
lucky for us the lethal gamma rays are
blocked by the Earth's atmosphere but
they do leave behind footprints for
astronomers to study after hitting the
atmosphere they produce cascades of
energetic particles these in turn caused
a faint glow that magic can see and hear
the plga observatory in Argentina it
doesn't even look like a telescope plga
consists of 1600 detectives spread over
three thousand square kilometers they
catch the particle fallout of cosmic
rays from distant supernovas and black
holes and what about neutrino detectives
built in deep mines or beneath the
surface of the ocean or in the Antarctic
ice could you call those telescopes
well why not after all they do observe
the universe even if they don't capture
data from the electromagnetic spectrum
neutrinos are elusive particles that are
produced in the Sun and supernova
explosions they were even produced in
the Big Bang itself
unlike other elementary particles
neutrinos can pass through regular
matter travel near the speed of light
and have no electric charge
although these particles may be
difficult to study they are plentiful
each second more than 50 trillion
electron neutrinos from the Sun passed
through you finally astronomers and
physicists have joined forces to build
gravitational wave detectors these
telescopes do not observe radiation or
catch particles instead they measure
tiny ripples in the very structure of
space-time a concept predicted by Albert
Einstein's theory of relativity
with a stunning variety of instruments
astronomers have opened up the full
spectrum of electromagnetic radiation
and have even ventured beyond but some
observations simply can't be done from
the ground the answer space telescopes
the Hubble Space Telescope it's by far
the most famous telescope in history and
for good reason
Hubble has revolutionized so many fields
in astronomy by modern standards doubles
mirror is actually quite small
it only measures about 2.4 meters across
but its location is literally out of
this world
high above the blurring effects of the
atmosphere it has an exceptionally sharp
view of the universe
what small double can see ultraviolet
and me infrared light this light just
cannot be seen by ground-based
telescopes because it is blocked by the
atmosphere cameras and spectrographs
some as big as a telephone booth dissect
and register the light from distant
cosmic shores just like any ground-based
telescope bubble is upgraded from time
to time
spacewalking astronauts carryout
servicing missions broken parts get
refurbished and all the instruments get
replaced with newer and state-of-the-art
technology Hubble has become the
powerhouse of observational astronomy
and it has transformed our understanding
of the cosmos with its keen eyesight
Hubble observed seasonal changes on Mars
a cometary impact on Jupiter
an edge on viewer Saturn's rings
and even the surface of tiny computer
it revealed the life cycle starts from
their very birth and baby days in the
nursery of dust-laden clouds of gas all
the way to their final farewell as
delicate nebula slowly blown into space
by dying stars or as Titanic supernova
explosions that almost outshine their
home galaxy deep in the Orion Nebula
double even saw the breeding ground of
new solar systems dusty disks around
newborn stars that may soon condensed
into planets the Space Telescope studied
thousands of individual stars in giant
globular clusters the oldest stellar
families in the universe and galaxies of
course
never before had astronomers seen so
much detail majestic spirals absorbing
dust lanes violent collisions
extremely long exposures of blank
regions of sky even revealed thousands
of faint galaxies billions of
light-years away photons that were
emitted when the universe was still
young a window into the distant past
shedding new light on the ever-evolving
cosmos double is not the only telescope
in space
this is NASA's Spitzer Space Telescope
launched in august 2003 in a way it is
Hubble's equivalent for the infrared
Spitzer has a mirror that is only 85
centimeters across but the telescope is
hiding behind a heat shield that
protects it from the sum and it's
detectors are tucked away in a jeweler
filled with liquid helium here the
detectors are cooled down to just a few
degrees above absolute zero making them
very very sensitive Spitzer has revealed
the dusty universe dark opaque clouds of
dust blowing infrared when heated from
within shockwaves from galaxy collisions
sweep up dust and telltale rings entitle
features new sites for ubiquitous star
formation
dust is also produced in the aftermath
of the stars death Spitzer found that
planetary nebulae and supernova remnants
are laden with dust particles the
prerequisite building blocks of future
planets and other infrared wavelengths
Spitzer can also see right thru a dust
cloud revealing the stars inside hidden
in the dark cause finally the Space
Telescope spectrographs have studied the
atmospheres of extrasolar planets gas
giants like Jupiter that race around
their parent stars in just a few days so
what about x-rays and gamma rays
well they're completely blocked by the
Earth's atmosphere and so without space
telescopes astronomers will be totally
blind to these energetic forms of
radiation x-ray and gamma-ray space
telescopes reveal the hot energetic and
violent universe of galaxy clusters
black holes supernova explosions and
galaxy collisions
they're very hard to build though
energetic radiation passes right through
a conventional mirror x-rays can only be
focused with nested mirror shells made
of pure gold and gamma rays are studied
with sophisticated pinhole cameras are
stacked scintillators that give a brief
flashes of normal light when struck by a
gamma-ray photon in the nineteen
nineties NASA operated the constant
gamma ray observatory at the time it was
the largest and most massive scientific
satellite ever launched a fully-fledged
physics lab in space in 2008 Compton was
succeeded by glassed the gallery large
area space telescope it will study
everything in a high-energy universe
from Dark Matter two pulsars meanwhile
astronomers have to x-ray telescopes in
space
NASA's Chandra x-ray observatory and
ESA's xmm-newton observatory are both
studying the hottest places in the
universe
this is what the sky looks like with
x-ray vision
extended features are clouds of gas
heated to millions of degrees by shock
waves in supernova remnants the bright
point sources are x-ray binaries neutron
stars or black holes that sucking matter
from a companion star this hot infalling
gas emits x-rays
likewise x-ray telescopes reveal
supermassive black holes in the cause of
distant galaxies matter that spirals
inward gets hot enough to glow in x-rays
just before it plunges into the black
hole and out of sight hot but tenuous
gas also fills the space between
individual galaxies in a cluster
sometimes this intracluster gas is
shocked and heated even more by
colliding and merging galaxies clusters
you more exciting are gamma ray bursts
the most energetic events in the
universe
these are catastrophic terminal
explosions of very massive rapidly
spinning stars in less than a second
they release more energy than the Sun
does in 10 billion years Hubble Spitzer
chandra xmm-newton and glass are all
versatile Giants but some space
telescopes are much smaller and have
much more focused missions take a role
for example this French satellite is
devoted to stellar seismology and the
study of extrasolar planets or nasa's
swift satellite a combined x-ray and
gamma-ray observatory designed to
unravel the mysteries of gamma-ray
bursts and then there's w map the
Wilkinson microwave anisotropy probe in
just over two years in space it had
already map the cosmic background
radiation to unprecedented detail w map
of cosmologists the best view yet of one
of the earliest phases of the universe
more than 13 billion years ago
opening up the space frontier has been
one of the most exciting developments in
the history of the telescope so what's
next
in Arizona the first mirror has been
cast for the giant Magellan telescope
this huge instrument will be built at
the last Campanas Observatory in Chile
it's seven mirrors each well over eight
meters across will be arranged like the
petals of a flower and together they
will capture more than four times the
amount of light any current telescope
can catch the Californian thirty meter
telescope plan for 2015 is more like a
giant version of keck hundreds of
individual segments makeup one enormous
mirror as tall as a six-story apartment
in your plans already for a European
extremely large telescope at 42 meters
in diameter its mirror will be as large
as an Olympic swimming pool twice the
surface area of the thirty meter
telescope these future monsters
optimized for infrared observations will
all be outfitted with sensitive
instruments and adaptive optics they
should reveal the very first generation
of galaxies and stars in the history of
the universe
moreover they may provide us with the
first true picture of a planet in
another solar system for radio
astronomers 42 meters peanuts they hook
up many smaller instruments to
synthesize a much larger receiver in the
Netherlands the low-frequency array so
far is under construction
fiber optics will connect 30,000
antennas to a central supercomputer
novel design has no moving parts but it
cannot observe in eight different
directions simultaneously loaf our
technology will probably find its way
into the Square Kilometre Array which is
now talking the witness of radio
astronomers
the International array will be built in
Australia or south africa large dish
antennas and small receivers will team
up to provide incredibly detailed views
of the radio sky and with a total
collecting area of one square kilometer
the new array will be by far the most
sensitive radio instrument ever
constructed evolving galaxies half
quasars blinking pulse ox no single
source of radio waves will be safe from
the spine eyes of the Square Kilometre
Array the instrument will even look for
possible radio signals from
extraterrestrial civilizations and what
about space
well after its fifth and final servicing
mission the Hubble Space Telescope will
be on active duty until 2013 so around
that time
its successor will be launched
meet the James Webb Space Telescope a
space infrared Observatory named after a
former naza administrator once in space
it's 6.5 need a segmented mirror unfolds
like a blooming flower 17 times as
sensitive as Hubble's a large sunshade
keeps the optics and the low-temperature
instruments in permanent shadow allowing
them to operate near a whopping minus
233 degrees Celsius the James Webb Space
Telescope won't orbit the Earth instead
it will be parked 1.5 million kilometers
from our planet in a wide orbit around
the sun off a century ago the Hale
telescope on palomar mountain was the
largest in history now an even bigger
one will be flying into the depths of
space we can only speculate about the
exciting discoveries it will make stay
tuned
meanwhile creative engineers come up
with revolutionary designs for new
telescopes all the time in Canada
scientists have built the so-called
liquid mirror telescope in this kind of
telescope the star light is reflected
not by a solid mirror but rather by the
curved surface of a rotating reservoir
of liquid mercury
because of their design mercury
telescopes can only look straight up but
their advantages is that they're
relatively cheap and easy to build radio
astronomers want to put the local like a
rail small antennas onto the surface of
the moon as far away as possible from
terrestrial sources of interference who
knows one day there might even be a big
optical telescope on the far side of the
Moon using space telescopes and
occulting discs x-ray astronomers hope
to improve their eyesight tremendously
in the future they may even succeed in
imaging the very edge of a black hole
interferometers launched into the
darkness of space may provide a novel
answer right now
Nasser is considering a project called
the terrestrial planet finder and in
Europe scientists are designing the
Darwin ra6 Space Telescope's orbit the
Sun and formation lasers control their
mutual distances to the nearest
nanometer together they have incredible
resolving power canceling out the light
from overbearing stars so scientists can
actually see earth-like planets around
other stars next astronomers must study
the light reflected by the planet is
Carrie is the spectroscopic fingerprint
of the planet's atmosphere who knows in
15 years time we may detect the
signatures of oxygen methane and ozone
the signposts of life the universe is
full of surprises
the sky never cease to impress no wonder
that hundreds of thousands of amateur
astronomers across the globe go out
every clear night to marvel at the
cosmos their telescopes are much better
than the instruments used by Galileo the
digital images even surpass the
photographic images taken by
professionals just a few decades ago
astronomers quest for cosmic
understanding the telescopic exploration
of the universe is only 400 years old
there's still a lot of uncharted
territory out there
we've come a long way since Galileo
began charting the heavens with his
telescope for centuries ago today we
still observe the universe with
telescopes for earth but in the
limitless regions of space the seed of
humanity lines in our seemingly endless
supply of ingenuity and curiosity we
have just begun answering some of the
greatest questions concede we have
charted over 300 planets around other
stars in our own Milky Way and located
organic molecules on planets around
far-flung stars these incredible
discoveries may seem like there's any
human exploration but the best is
undoubted yet to come
you too can join the discovery look up
then one
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