or foreskins our tires at the base of everything lie the eternal questions of
origins these are questions that priests philosophers along with us scientists
have all examined we research extrasolar planets to find the origins of life and
for the origins of the universe people we try to observe the universe in its
infancy and that's the main motivation for building bigger and better
telescopes and evermore sophisticated instruments
even though light travels at 300,000 km/s the universe is so vast that light
from celestial objects takes a long time to reach us
the sun's light takes 8 minutes to traverse the a hundred and fifty million
kilometers between the Sun and the earth while light from the closest star
Proxima Centauri takes four years our neighboring galaxy Andromeda is 2.5
million light years away meaning that when we look at the Andromeda galaxy we
see it as it was more than 2 million years ago by attempting to observe even
more distant galaxies nearly 13 billion light years away we can go back in time
to approach the birth of the universe us hollow from the core table tea
astronomers are contemplative the only thing we can observe is light actually
we would rather do experiments like in other Sciences way a galaxy for instance
or stop it from turning to see what happens but of course we can't do that
our one and only source of information is light
and I'll girl of course we can take pictures look at the shape of objects
and see their colors but because light transmits information about the atoms
that emitted it by using quanta of energy or quantum mechanics we can do
much more than that we can find the signature of those atoms
a sort of unique genetic code and that's really powerful as it means we can
determine the chemical composition the physics of the gas even the movements of
the stars thanks to the Doppler effect the instruments that enable us to obtain
information by analyzing light are called spectrographs they are absolutely
essential to us from associate born
since its invention in the 19th century the spectrograph has been a fundamental
tool in astronomy in the 1990s a new type of instrument was invented in
Europe the 3d or integral field spectrograph for the first time we could
obtain spectra of a wide area of the sky containing many astronomical objects the
first generation of instruments based on this new concept is now installed on
large telescopes around the world with its many telescopes in Chile the
European Southern Observatory or ESO is the spearhead of European astronomy many
examples of first generation 3d spectrographs already in place at the
focus of the four very large telescopes with 8.2 meter diameter mirrors at the
Paranal observatory
as technology advances after say ten years you can build a much better camera
or a much better spectrograph and put it on the telescope and make it more
powerful but it takes five to ten years to do so early 2000s and planning was
going on at easel hmm we should have IDs for new more powerful instruments called
the second generation instruments lapel door for the lasers tender immediately
gave us a chance to move up again and to propose something that was based on
everything we had learned during all those years something much more
ambitious which would mean we'd be able to observe the very distant universe
like never before and so that was the very beginning of the Meuse project the
project in the past and we did have instruments that in a way operate like
we used integral field spectrographs they make images and spectra at the same
time they have been around for 20 years and both you know Lyon and also our
Institute in Potsdam have been very successful in using this type of
observations but what new is now followed really for the first time
introduces is to combine this capability with the capability of a survey
instrument meaning really to look at a significant part of the sky
not just at one galaxy but really at a significant part of the sky and have
lots of stuff in there and everything with this imaging plus spectroscopy
capability that's a very new approach to to do astronomy
Mews the multi-unit spectroscopic explorer is composed of not just one 3d
spectrograph but 24 when the light of the galaxy captured by the telescope
enters the instrument the first optical element the light encounters is the D
rotator which compensates for the Earth's rotation the stabilized image is
then magnified by a pair of mirrors next the beam enters the first field splitter
the image of the galaxy is split into 24 sections
resulting in 24 separate optical beams these beams are distributed by a group
of mirrors and lenses to the 24 modules
the light is again split by a second field splitter called a slicer the
masterpiece of Muse the slicer is composed of two series of 48 spherical
mirrors which split the beam into 48 slices the light reflected by each small
mirror enters the spectrograph where it is dispersed according to its wavelength
the detector registers the spectrum of a small part of the galaxy this process is
repeated for each of the 48 beams the detector is then completely illuminated
the same thing occurs simultaneously in each of the 24 spectrographs the
resulting 400 million pixel image holds the spectral information of every part
of the galaxy if you the more obviously no laboratory
could take on a project as complex as muse alone no one would have had the
strength or capacity for that so I brought together a group of laboratories
in Europe which together have the expertise for such a project five
research laboratories join the Astrophysical research center of Liam to
develop muse along with ESO the process began in 2004 with the conceptualization
design and construction involving experts in optics mechanics electronics
and software the different phases took nine years and involved a hundred
researchers technicians and engineers to overcome the many challenges
particularly in the development of the slicer the key component of Muse offered
a measure so you have to understand that in the beginning when we launched the
project as is often the case we didn't actually know how to create this slice
Idoko quality project we've made a small prototype but that's all and so as the
project went on we had to demonstrate that we could in fact do it so we
launched a whole load of tests made a whole lot of things in metal with
different technologies in the optical field with a variety of manufacturers in
Europe and in the USA and each time it didn't function each time there was
something that didn't work and so at one point we really thought that the project
would have to stop there no slices no Muse and then suddenly a
French manufacturer came up with a technology that meant we could finally
create the slicer and of course there wasn't just one but 24 to be made
we were saved that was us hope he offered the Assembly of Muse began in
Leon in 2010 thousands of components arrived from all over Europe it took
three years to assemble calibrate align and test the instrument
in September 2013 after final tests Muse was disassembled carefully packed and
shipped to Chile
mr. David Musa rived in dozens and dozens of boxes several lorry Lords
arrived in Canal and our first concern was that everything arrived in one piece
because you see their unique pieces and if one part had been broken there
wouldn't have been time to make another one quickly enough so that was already
very stressful but everything was fine and so once all the crates with all the
pieces had been unpacked at paranal and we saw that everything was alright
it had to be assembled tested and aligned and for muse which is one of the
biggest instruments to install on the VLT the biggest in fact that phase took
a long time but the really stressful part of this marathon was respecting the
deadlines the Knights that had been allotted to us for the commissioning on
the sky had been fixed a long time in advance and we absolutely could not miss
the method that was a new experience for us because in earlier projects we
disassembled the instruments put them into single pieces and reassembled them
again on the telescope on the platform but for Muse it turned out is not
feasible because news was too complicated to do all this assembly and
especially these alignments inside of the telescope dome
it was decided that we will lift the instrument as a total in the single lift
into the dome and there is only one way to enter the dome with a big-sized
instrument and that is the slit for observation I wonder how you do sleep I
imagine our state of mind beforehand we knew that it was the crucial part of the
operation and that the weather would play a key role in it being successful
since we were going to unpack the instrument and leave it outside before
installing it in the telescope but of course just as we are about to do this
there was a high wind and risk of rain so we slowed down a bit and waited and
then we had a meeting and looked at the weather forecast I made the decision to
go ahead
one of the biggest risks was of course damage to the instrument but there was
also another parameter the alignment this had taken more than two months to
do in the integration Hall and if it had become misaligned we would have had no
choice but to take it back down again in all this
and then it was lifted up to the 15 meters elevation above our heads but to
be honest at that moment I thought I would be totally excited and fear that
the the instrument would could fall down
I noticed big you take another critical element was that the telescope has
mirrors and we would have had a big problem with the mirrors if the Sun
shone on so we started lifting at around 5:00 5:30 a.m. and when we'd finished at
them we only had about 10 minutes before the Sun arrived on the main mirror which
was the moment when we absolutely had to close the shutter so not only was it a
very delicate technical operation but one that had to be done in a very
limited space of time you tell you tell time
now from Yahoo it was the first time that a light other than ambient light or
from a calibration lamp would reach the instrument the light of a star or of a
galaxy for example I wanted to symbolize that moment by choosing a special object
that was hidden and secret okay so I chose the captain stars it because it's
13 light-years away which means that the light left this star in 2001 at the same
time that we made the bid for ease O's 10 member more you kept on your I love
editor for the RISM Creusot for 13 years the light had traveled
across deep space at 300,000 kilometers per second and arrived 13 years later in
muses channel number 6
it was really amazingly symbolically fried I shared this with the team when
they asked me I also told them that it was because the light from the star had
gone straight ahead whereas for us it had been a bit less straightforward
formula we a slap on your phone it was the first light and it was the first
time that we'd taken a picture of the sky personally I was under a lot of
pressure because we had installed the instrument and then spent a week
aligning it correctly with the telescope so when we took the first image
it was also validation that the instrument was exactly opposite the
telescope city love was the result of 10 years of work and it functioned we could
see our stars they were clearly defined then we could put them in the right
order well he had succeeded minute so now we've had this instrument over to
the scientists and we knew that they were going to have a lot of fun like
easily simulating
Muse was set up but before entering service it had to pass a battery of
tests and adjustments this stage known as commissioning required many nights of
data acquisition so that the engineers and researchers could obtain muses
optimal performance
Siddiq on this screen we can see the reconstructed image of the area of sky
which is being observed you can see the different objects that we have marked
and for each of the objects you can see the spectra which gives us the
characteristics and tells us what it is if it's a galaxy or a quasar or another
object of scientific interest of the colors report a one of the big
challenges of this project was being able to analyze efficiently the enormous
amount of data that the instrument provides sorry about the project Edsel
you see it's capable of producing 400 million bytes of data a minute the
volume of information can be considerable but it's not only the
volume it's also the complexity the image that arrives on the detector has
been cut several times into small pieces by slices and by field splitters and so
it's extremely complicated for and you have to retrace algorithmically what
happened on the detector and compare it to what was in the sky solution but Muse
fundamentally creates a lot of pixel data on some detectors and if you look
at that well he cannot make much head nor tail of it so it's it's a very
complicated process we have an expert in the team who wrote what we call the data
reduction software and that basically puts these all these pixel data together
to make images spectra the combined data cube and so on
in February 2014 during the validation phase Muse observed the Orion Nebula to
test its ability to analyze a large region of the sky in less than two hours
Muse took more than 60 pictures of the nebula that is 2 million spectra 100
times more than available so far after processing the data was arranged in a
cube composed of a series of four thousand images of different wavelengths
the analysis of this data reveals a number of distinct chemical elements as
well as the physical conditions of the gas in the nebula compared to simple
images the data cube produced by Muse is so rich in information that researchers
will need many months to fully analyze its contents and publish the results so
the real thing is what we got with the Orion Nebula was really what we hope for
even much better it was so spectacular they really the because there's a lot of
gas and that gas is in motion and there's stars hot stars that excite this
gas that bring it to radiates in different parts of the electrometric
spectrum so the earth all sorts of you can easily visualize this with very
colorful maps and that's what we've done afterwards
yeah and really the interesting things this is was a showpiece for the
capabilities of Muse but it also contains an incredible richness of
scientifically valuable data
every six months the members of the Meuse consortium meet for busy weeks at
these times they report on the status of the observing programme and discuss the
latest results throughout the week professors postdocs and students of many
nationalities come together with one objective to extract scientific
information from the light analyzed and dissected by muse numerous topics are
explored in particular my own interest is on how galaxies like our own Milky
Way galaxy how galaxies change with time how they evolve how they are formed in
the early universe how they then develop over time what controls how they develop
and so on and we know that a key part of that is the interaction with gas in the
universe how gas flows from the surrounding universe onto the galaxies
and that's then the fuel out of which stars like the Sun are eventually made
and we know that surrounding galaxies there is gas it's the gas leftover if
you like from the Big Bang we see that in absorption against background objects
but we that always just gives us a sort of one-dimensional probe it's like a
needle through literally a needle through a haystack with Moo's we can
actually now see where this gas is in a sort of three-dimensional volume and so
what we want to do with Muse is to understand this process of how gas flows
from the surrounding universe onto onto galaxies
I would say holy grails of my own research field has been to detect this
web of gas which we think must be there in the early universe out of which
galaxies are are forming and muse really is the best instrument now to really try
and see this
we observe quasar so-called quasars and these are some of the brightest sources
in the universe and what the quasar is supermassive black hole gas is spiraling
in because of the gravity of the supermassive black hole and because the
gravity is so strong with the gas moves really really fast as it spirals into
the black hole and because it's moving so fast there's a lot of friction
between gas layers that are moving at different speeds the gas gets really
really hot and as a gas hot its emits a huge amount of radiation now we were
using those quasars as tools not to study than themselves but as flashlights
because it's so bright you can see them all the way across the universe and you
see a flashlight and if you then check what the gas on its way from the quasar
to you the telescope The Observer what that gas around the galaxy that's in
between you absorbs then you can learn about the gas around a galaxy that you
can't observe in any other way but to learn how that relates to gas inflow and
outflow of the galaxy you need to know where the galaxy is and that was the
bottleneck and we couldn't find the galaxies only the very brightest ones
with Meuse we can go much fainter one two tours of magnitude fainter so we can
find many more galaxies in fact I realize we could find as many galaxies
as we could see absorption lines so we could really start to correlate the gas
that we see in absorption with the galaxy is detected by Muse and in that
way for the first time learning about the gas inflows and outflows of galaxies
that are far away and these are important because far away in astronomy
means further back in time and the muse we can study this process
at a time when the galaxies are most active in the history of the universe
and they were forming stars very vigorously and because of that's
producing big explosions that blew a lot of gas back into intergalactic space
kinetic art art they do ice core drilling in that arctica to go back in
climate history and it's the same when we observe a skyzone very deeply we go
back in time now I'm particularly interested in galaxies those huge groups
of millions of stars and the millions of galaxies in the universe we want to know
when they were formed how they evolved I don't and so it's like very deep core
drilling of the universe which means we can see galaxies at different ages when
they were infants adolescents adults and so on and that's how we try to retrace
their story news is really the perfect instrument for doing this I think it's
brilliant because I used to want to be an archaeologist and I've rediscovered
the love I had for it in my youth with Muse I'm doing the archaeology of the
universe
in 2014 over the equivalent of four nights
music served an area of the Hubble Deep Field this field had previously been
imaged in the year 2000 by the Hubble Space Telescope using very long
exposures to obtain color images of hundreds of galaxies the Muse data cube
of this field is rich in information as we go through the cube we advanced in
wavelength from blue to infra red a
number of bright points can be seen which vary in brightness with wavelength
these are mostly galaxies from the brightness variations we can deduce the
physical properties of the galaxies for example which types of stars are present
there we now select a small region of the data cube two zones to be precise
the first is the center of a bright galaxy the second is empty on the Left
we see a spectrum appear near 520 nanometers we encounter a bright
emission line the galaxy shines intensely at this wavelength showing the
presence of hot oxygen in the galaxy
in the red we suddenly see another line in the second part of the cube there
where nothing was visible before a galaxy is now revealed thanks to the
presence of ionized hydrogen by measuring the precise wavelength of the
emission line it's possible to deduce the distance to the galaxy it's a very
distant 113 billion light-years away and we have observed it just 1 billion years
after the Big Bang
Nalini may the quality of the Hubble telescopes image allows you to see a
galaxy and its form with precision but what you are essentially seeing is how
much light is received at a given moment in that galaxy like a techie I think
with the spectrum you also have the distribution of the energy of this light
all its wavelengths and all its colors a sow fits and we're done and this
provides a lot more information like the speed at which these galaxies rotate the
movement of gas chemical elements and the number of stars of different ages
young and old that the galaxies are composed of into size and is not for my
sake do men do all this information put together enables us to estimate what
stage of development the galaxy has reached
gasai Moo's well thanks to music we could measure the distances of something
like 180 galaxies in the same field of vision and we have discovered about 30
new very distant galaxies in that same field that couldn't be seen with Hubble
luckily we are aware that we have made a very beautiful instrument which is now
considered not only by us but by the community of those who have really used
it to be the Rolls Royce of astronomy after being used for a year a remarkable
number of articles have been published using data from it mostly by people who
are not on the Meuse team it's really great to see that people outside of the
project can use this instrument easily you can get results and extremely good
results very quickly who thought was he talking
you
to meet that dolls in 2014 I lived through some truly extraordinary moments
it was like a dream come true it was an idea a vague plan that became in reality
a fantastic machine to travel back in time they're all true it was a technical
scientific and human adventure throughout it I met some remarkable
people with remarkable intelligence devoted to the project and together we
made something extraordinary that none of us could have done alone Muse will be
used by ESO and by us for maybe the next 10 15 or 20 years so I think that Muse
will market Sarah as an important contributor to scientific discovery
you're about the only person around it doesn't have TV coverage of the food and
I don't need it man you got the flag up now and you can see
the deal yes we are getting a TV picture with you now
at one of them
but daya please for me


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