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00:00the night sky is a time machine the further we look out into the universe the further back in
00:12time we reach what we see in the night sky is only a small percentage of the contents of the
00:18universe most is dark matter and dark energy we know it exists but its nature eludes us for the
00:28moment
00:58no longer hampered by a hazy often polluted atmosphere telescopes and other sensors have
01:13been able to obtain clearer images from orbit thanks to advances in technology and engineering
01:18in the 1960s satellites began to explore the cosmos surrounding us they saw beyond visible light into
01:28ultraviolet infrared x-ray and even gamma rays like the universe itself our understanding of its
01:36beginnings construction evolution and future is evolving and constantly expanding
01:42in the last two decades of the 20th century the United States and other nations began to develop
01:49more substantial research programs utilizing larger and more complex space-based telescopes
01:56for hundreds of years thousands of years humans have thought the universe is a very static place
02:03if you go out at night and look into the night sky you will see that things don't really change much
02:09the universe appeared very static for a long time we now know this is not true the universe is a highly
02:16dynamic place and things are happening all the time every single second a star explodes in a gigantic
02:23supernova explosion somewhere in the universe and we have to go and find it we have to build instruments
02:29that are capable of finding those unforeseen events the cosmic background explorer or kobe satellite
02:36started crystallizing the big picture of the universe by mapping the microwave background radiation
02:42leftover from the early universe its successor w map created the most detailed portrait of the infant
02:49universe well because it takes the light over 13 billion years to reach us we are seeing now what
02:55the universe looked like then over 13 billion years ago so it's a it's a fossil remnant of what the early
03:02universe was like and just like fossils are used to study the past we use this light to study what the
03:08universe was like way back near the near the very beginning and you can see in their blue spots and red spots
03:17and what those correspond to are slightly hotter and colder images of the sky that's that's a picture
03:24there those hot and cold spots that pattern it's really the it's the afterglow of the big bang on a sort
03:32of deeper long-term times level it's this amazing consistency that the picture we can put together of the
03:40universe is is relatively simple that the pieces fit together it's uh it's a stunning confirmation of of of this of the study of
03:50cosmology for many years now that's it's just built up and and here it is in some ways that we're getting to know the cosmos
03:57like we know our own backyards he says plank spacecraft joined the fleet and expanded on their observations together they were able to map vast regions in multiple wavelengths
04:08enabling astronomers to determine the size shape and age of the known universe
04:13so 370 000 years after the universe began in a big bang all that existed was a hot plasma similar to a candle flame
04:22protons and electrons seen as the red and green balls were bouncing around scattering the light
04:28particles of light called photons shown in blue couldn't go far without colliding with an electron
04:34as the universe cooled the protons and electrons could pair up forming hydrogen atoms and the light was free to travel
04:41and the light was free to travel it's been traveling freely ever since through the dark ages before there were stars
04:47then past the formation of the first stars
04:51as the universe expanded photons lost energy changing color
04:55changing color
04:57they went past clusters of galaxies
05:00the path of the photon is slightly bent by the gravity of the clusters
05:06now and then going through a cluster an electron that green ball would collide with some of the photons
05:12they would change their path
05:14past more matter more little wiggles due to gravity mass
05:19the photons traveled for thirteen point eight billion years
05:24before they reached the plank detectors
05:26and died a glorious death
05:28giving up the information that they had gleaned
05:31passing through the entire universe to our instruments
05:34and enabling us to make this beautiful map of the universe
05:38the various satellite telescopes have sensors designed for use in multiple wavelengths of the electromagnetic spectrum
05:57from near to far infrared light through visible and ultraviolet frequencies to x-ray gamma and cosmic ray detectors
06:05each can reveal unique aspects of the construction of stars
06:11nebulae galaxies and the exotic blazers and black holes
06:16however in the public's eye the poster pin-up star of the latest generation
06:23would undoubtedly be the Hubble Space Telescope
06:26over its 25 year lifespan Hubble has produced some of the most amazing imagery of the cosmos
06:39as it delves back in time through visible and infrared light
06:43another advantage of Hubble is its long lifespan thanks to several maintenance missions
06:54which allows it to study objects over a long period of time with some amazing results
07:01newborn stars eject streams of matter into the surrounding star forming region
07:07known as Herbig Haro objects
07:10these supersonic jets can be seen to change over a very short time span
07:15if you see just a single picture from Hubble you can interpret it in many different ways
07:21but the fact that Hubble has been around for as long as it has been means by taking multiple images
07:26you can actually stitch them together and watch how the material moves
07:30and so that really gives you the only way to give true insight into the physics of the dynamics of what's going on
07:37the horse head nebula in the Orion constellation silhouetted by glowing gas is a good example
07:48infrared can see right through revealing its dark secrets
07:52the Spitzer telescope is one of NASA's great observatories
07:59Spitzer is an infrared telescope which means it sees through the dust that's out in space
08:04and by seeing through the dust we get to pinpoint the stellar nurseries that are out there where stars are being born
08:13we've been flying for about 10 years that's about 33,600 days
08:18we have 5,000 published papers that means every day a new paper based on Spitzer data
08:24announcing new results and new discoveries is published which to me is absolutely amazing
08:30Spitzer has made several surprising revelations within our solar system and beyond
08:36it helps pinpoint some of the most distant galaxies in the universe
08:40and Spitzer's ultra-high resolution map of the Milky Way
08:44substantially improved our understanding of our own galaxy structure
08:49Japan and ESA had launched their own infrared telescopes in various infrared wavelengths
08:56the European Herschel in particular focused on massive star formation regions
09:03we are really happy to have new things and to understand trying to understand
09:10because we are making a new step towards our understanding of massive star formation
09:15so the idea is that Herschel can reveal this population of highly embedded star that are formed in gas and dust cocoon
09:25but that are not visible at optical wavelength for example
09:30so we need Herschel to detect all this population of very young stars
09:34The next great space-borne infrared telescope is the James Webb Telescope
09:40which is nearing test completion in preparation for its launch in 2018
09:46it will have a 6.5 meter primary mirror almost three times larger than Hubble
09:52however ground-based telescopes are also working in the infrared spectrum
09:59so there's a large complementarity between space and ground
10:07from space with the Hubble images you can characterize the images
10:11you see the images much better
10:13with the ground-based telescopes you then can take that light
10:17and look at spectra and then find the redshifts for example for distant galaxies
10:22or you can take infrared observations which Hubble couldn't do for a long time
10:26to then see how these objects look in the infrared
10:30Together they have delved into the star-forming nebulae
10:34left over from exploding supernova and witnessed the birth of stars
10:39Another observational tool in the electromagnetic spectrum for astronomers and cosmologists
10:57is the X-ray band
11:00An amazing discovery of the last 20 years is that every galaxy like our own Milky Way
11:05has a massive black hole at its heart
11:08and as material from this galaxy dust and gas falls onto this central black hole
11:15it radiates and we can see that
11:18so if we look at the sky in visible light we see stars
11:21if we look at the sky in X-rays we see black holes
11:27You can observe X-rays from very distant objects
11:31so you can investigate the cosmic structure of the universe
11:40so you investigate the matter distribution in the universe
11:45while observing the galaxies, the active black holes in the center of the galaxies
11:52to very far distances
11:54and this is very important for cosmology
12:00and to learn about the origin and the evolution of our universe
12:07X-rays are absorbed in our atmosphere
12:10so X-ray detectors must be placed at either high altitudes by balloon or into orbit
12:17NASA's flagship X-ray telescope and one of their great observatories is Chandra
12:23If you want to find black holes, you want to use an X-ray telescope
12:28What we're tending to find is that a cluster of galaxies has a bright central galaxy in the middle
12:34it's often an active galaxy or a quasar
12:37so a supermassive black hole in the middle of a big galaxy
12:40because when the cluster is forming, a lot of material tends to fall to the middle
12:44so you get the biggest galaxy in the middle
12:47So you see the power of an observatory
12:49an observatory like Chandra with a state-of-the-art telescope
12:53and these imaging and spectroscopic capabilities of its science instruments
12:57can do things that maybe weren't even things that you planned on doing
13:00because you didn't know about them at the time
13:02and a lot of the science with Chandra falls in that category
13:06The most recent telescope launched is New Star
13:10which has the ability to focus X-rays for a much sharper image
13:14One of New Star's main scientific goals
13:17is to make a full census of black holes in the universe
13:21X-rays have also revealed the explosive processes of NOVA
13:25seen only at these wavelengths
13:28ESA have their XMM Newton
13:32studying cosmic evolution
13:34and INTEGRAL, the International Gamma Ray Astrophysics Laboratory
13:38looking at gamma ray frequencies
13:40revealing unseen structures
13:42and new sources of gamma rays
13:46So INTEGRAL is important because it's one of the few satellites
13:50which look in gamma rays
13:52and together with other satellites
13:56and observatories around the Earth
13:58you can get a complete picture of how these stars evolve
14:02and without INTEGRAL you're missing a large piece of the puzzle
14:06We want to know how did they produce the elements which we are made of
14:10These are the objects which throw all the different kinds of material into the universe
14:18and they wander off into space
14:22We are made of all these elements which are produced by the supernova
14:26So it is important for us to know where does life originate
14:32and how does it originate
14:34Gamma rays are at the top of the electromagnetic spectrum
14:38the most energetic and powerful photons
14:41which stream from black holes, exploding stars
14:45and even from our own star, the Sun
14:50Originally called GLAST
14:52the Fermi Gamma Ray Space Telescope
14:54observes the entire sky in high energy gamma rays every three hours
14:59creating the most detailed map of the universe ever known at these energies
15:05When it detects a new gamma ray burst
15:07it works in conjunction with the SWIFT satellite
15:11Then SWIFT is able to spin rapidly across the sky
15:15and point an X-ray telescope
15:17and an optical ultraviolet telescope
15:19at the possible location of the gamma ray burst
15:23BLAST is primarily devoted to seeing a new energy range
15:28It's designed to pick up at the upper end of the SWIFT energy range
15:33and carry it on up to much higher energies
15:35And it allows you to just see, you know, stranger and more exotic things
15:39the further up in energy that you go
15:44GLAST and SWIFT are very different
15:46SWIFT is like a nimble small satellite that points here and there
15:49but it isn't surveying the whole sky
15:51it's pointing in its particular objects
15:54GLAST looks in the high energy gamma ray sky
15:56looks over the whole sky at all times
15:59So when we see something interesting with GLAST
16:02we can ask SWIFT to go look at it with their other telescopes
16:06and gain additional information about it
16:08We don't know what will happen over the next ten years
16:11hoping that SWIFT will still give us exciting data
16:15but what we do know is that SWIFT will give us exciting new data
16:19because of its pure nature
16:22this is what it was built for
16:24to study new, unforeseen, unexpected events
16:27and they will inevitably be happening
16:29There is one more type of radiation being studied in orbit
16:33cosmic rays
16:34The eight-ton cosmic ray particle detector
16:37called the Alpha Magnetic Spectrometer or AMS instrument
16:40is attached to the International Space Station
16:43Cosmic rays consist of protons, alpha particles, atomic nuclei of heavier elements
16:51electrons, their antimatter partner positrons and gamma rays
16:56Studying these particles may answer some fundamental questions
17:00like the unexplained absence of antimatter
17:03and the nature of dark matter in the universe
17:06Collaboration of positrons is important
17:15because when you have dark matter collision with another dark matter
17:27you produce excess positrons
17:31So, the characteristics of the excess positrons
17:36tells you what's the origin of dark matter
17:54About 80% of the matter in the universe is invisible to telescopes
17:59This dark matter neither reflects, absorbs nor emits light
18:04Yet it interacts with matter via a gravitational influence
18:08which can be seen in the orbital speeds of stars around galaxies
18:12and in the motions of clusters of galaxies
18:15Yet, despite decades of effort
18:18no one knows what this dark matter really is
18:22This visualization shows galaxies composed of gas, stars and dark matter
18:28colliding and forming filaments in the large scale universe
18:33providing a view of the cosmic web
18:35It is believed that dark matter provides the framework for this web
18:40Galaxy clusters are the largest gravitationally bound structures in the universe
18:46It is also believed that after the Big Bang
18:49the universe originally decelerated in its expansion
18:53but then changed gears and began to accelerate
19:00Important discoveries in astronomy and astrophysics
19:04was the discovery of dark energy
19:07and that is that the universe is accelerating apart
19:11What people are trying to do using various different techniques
19:17and again in all the different wavelength bands
19:19is to measure the parameters to characterize the dark energy
19:26With a launch date set for 2020
19:28ESA is building Euclid
19:30A space telescope which, it is hoped, will chart dark matter
19:34and dark energy's effect on the universe
19:39I am working on Euclid
19:41that is a mission to map the universe
19:45and for that we built a highly precise telescope
19:49in which we can map dark matter structures
19:52as well as derive the properties of the dark energy
19:56Understanding dark energy will allow us to understand the future of the universe
20:01The interesting thing is, we get more and more dark energy
20:06Why? Because our universe is expanding
20:09and with our expanding universe
20:12we get more dark energy in our universe
20:15Now the ordinary matter, so dark matter and normal matter
20:20is not expanding, it's diluting
20:22So the fraction of dark energy compared to normal matter
20:28is increasing in time
20:31When the universe expands more and more
20:33we get more volume of our universe
20:36we get more space and we get more dark energy
20:39The leading particle physics model for dark matter
20:42is called weakly interacting massive particles
20:45or also known as WIMPs
20:46These guys just fly through the universe
20:49without even bumping into anything or each other
20:52The idea of two WIMPs coming together
20:55annihilating and forming gamma rays
20:58is kind of like two bullets hitting head-on in a crossfire
21:01It's very rare
21:03But when you go to the area around a supermassive black hole
21:07we expect the density to be much higher
21:09so the probability of annihilation is much higher
21:12in this detection with a gamma-ray telescope
21:17In his theoretical process, Schnittmann's computer simulation
21:21shows particles of dark matter around a massive spinning black hole
21:27All of the action takes place close to the black hole's event horizon
21:31the boundary beyond which nothing can escape
21:34in a flattened region called the ergosphere
21:37Within the ergosphere, the black hole's rotation drags space-time along with it
21:43and everything is forced to move in the same direction
21:46at nearly the speed of light
21:49Concentrated, fast-moving dark matter particles collide and make gamma rays
21:54but only some of this high-energy light can escape the black hole
21:58in this case from the left side
22:00where the black hole is spinning towards us
22:03giving us a lopsided glow of high-powered gamma rays
22:07The simulation tells astronomers that there is an astrophysically interesting signal
22:13they may be able to detect as gamma-ray telescopes improve
22:17Schnittmann believes this would be conclusive evidence of the WIMP model
22:22To me, dark matter, black holes, two of the most elusive things in the universe
22:28coming together to help explain each other is quite poetic
22:33Future missions will see a gravitational wave observatory to study gravity waves
22:42and test Einstein's theory of general relativity
22:45The Athena mission mapping hot gas structures
22:51and searching for supermassive black holes due to launch in 2028
22:56The Sloan Digital Sky Survey, the most ambitious astronomical survey ever undertaken
23:04will provide a three-dimensional map of about a million galaxies and quasars
23:09The recently refurbished and upscaled CERN Large Hadron Collider
23:16is one of the tools in search of WIMPs and other exotic particles
23:20that may help explain the fabric of the cosmos
23:27Then perhaps the scientists, astronomers and engineers can turn their attention
23:32to other mysterious theories brought about by particle physics
23:35such as multiple dimensions, entire universes beyond our own
23:39and what lies beyond the event horizon
23:43These in time will become the new frontier
23:47The New Frontier
23:50The New Frontier
23:56The New Frontier
24:01The New Frontier
24:03The New Frontier