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The Universe Presented by NASA s Chandra X ray Observatory Like the jelly beans in this jar the Universe is mostly dark about 96 percent consists of dark energy about 73 and dark matter about 22 Only about 4 6 percent the same proportion as the lighter colored jelly beans of the Universe including the stars planets and us is made of familiar atomic matter X rays can help reveal the secrets of the darkness X ray astrophysics is crucial to our understanding not only of the Universe we see but the quest to determine the physics of everything Dark Universe two that we know the least about yet nothing less than the ultimate fate of the The two largest pieces of the Universe dark matter and dark energy are the together and dark energy tends to drive it apart A full understanding of this cosmic struggle will require major observational and theoretical breakthroughs Universe will be determined by them Dark matter tends to pull the Universe Dark Energy At the close of the 20th century our perception of the Universe was jolted Instead of slowing down after the Big Bang the expansion of the Universe was found to be accelerating Was the cosmic acceleration due to Einstein s cosmological constant a mysterious form of dark energy or perhaps a lack of understanding of gravity The answer is still out there By studying clusters of galaxies X ray astronomy is tackling this question using powerful techniques that are independent of other methods currently being employed or proposed for the future Observable Cosmos our eyes and telescopes This includes all intergalactic and interstellar gas and The remaining 4 of the Universe is composed of everything we can see with dust stars planets and life Before dark matter was discovered in the 1930s Black Holes Dark Matter The next largest chunk of the Universe s budget is another unknown dark matter Of all of the material we know about because we can see its gravitational effects about 85 is composed of matter that emits no light and is radically different from material found in planets and stars X rays can be used to study the effects of dark matter in a variety of astronomical settings and thus probe the nature of this mysterious substance that pervades the Universe this 4 was our entire Universe Scientists now use their telescopes and computers to learn ever more about the exciting objects and phenomena in the observable cosmos but also to glimpse through keyholes into the much larger Dark Universe Galaxy Clusters Black holes once the subject of science fiction are now science fact X ray telescopes have been crucial in this shift of thinking While many things have been learned about these mysterious objects much more remains to be discovered In fact black holes provide a natural arena for quantum mechanics and general relativity to meet and clash This means that if we are ever to unify the theories of physics the much sought after goal of the physics of everything we need to push forward the studies of black holes Supernovas Galaxy clusters are the largest structures in the Universe that are held together by gravity These mammoth objects can contain thousands of individual galaxies are immersed in vast clouds of hot gas and are held together by immense amounts of dark matter The hot gas which radiates at temperatures detectable by X ray satellites like Chandra contains much more mass than the galaxies themselves Their size and mass along with their rich reserves of dark matter make galaxy clusters valuable cosmic laboratories for the study of the properties of the whole Universe Missing Baryons Supernovas are produced when stars end their lives in spectacular explosions so bright that they outshine their home galaxies During their lives stars convert hydrogen and helium into heavier more complex elements which are distributed into space when the star explodes Nearly everything on Earth including life owes its start to the demise of earlier generations of stars that went supernova The remnants of supernovas can glow in X ray light for thousands of years and reveal their secrets to sensitive X ray telescopes Our Universe questions in the Universe In the past decade Chandra has demonstrated that X rays Astronomers use every appropriate means at their disposal to investigate the biggest Astronomers have known for some time that about half of all of the baryonic matter a k a protons and neutrons in the recent nearby Universe is unaccounted for It s all there in the early Universe so where did it go One idea is that these missing baryons became part of an extremely diffuse weblike system of gas clouds from which galaxies and clusters of galaxies formed One of the best ways to detect these missing baryons is through their faint but observable X ray signatures are a fundamental part of the modern astronomer s toolkit Many wavelengths One Universe Energy Distribution of the Universe 73 Dark Energy 22 Dark Matter 4 6 Everything else including all stars planets and us Download the Dark Universe podcast from http chandra harvard edu resources podcasts sd html HOW MANY JELLY BEANS FILL A ONE LITER CONTAINER There are many possible calculations but this is one approximately 80 of the volume of the bottle is filled How big is a jelly bean A typical jelly bean would measure about 2 cm long by about 1 5 cm in diameter The number of jelly beans is the occupied volume of the container divided by the volume of a single jelly bean Do jelly beans completely fill the container Number of beans occupied volume of container volume of 1 Bean The irregular shape of jelly beans result in them not being tightly packed The volume of one jelly bean is approximated by the volume of a small Credits Jelly Bean Image Fermilab Pie Illustration NASA CXC M Weiss Dark Energy NASA STScI G Bacon Dark Matter 1E 0657 56 X ray NASA CXC CfA M Markevitch et al Optical NASA STScI Magellan U Arizona D Clowe et al Lensing Map NASA STScI ESO WFI Magellan U Arizona D Clowe et al Observable Cosmos Earth Aurora NASA MSFC CXC A Bhardwaj R Elsner et al Earth model NASA GSFC L Perkins G Shirah NGC 4696 X ray NASA CXC KIPAC S Allen et al Radio NRAO VLA G Taylor Infrared NASA ESA McMaster Univ W Harris Galaxy Clusters Perseus Cluster NASA CXC IoA A Fabian et al Supernovas Chandra X ray Center cxcpub cfa harvard edu cylinder 2 cm long and 1 5 cm in diameter Volume of 1 Jelly Bean pi x 1 5cm 2 2 x 2 cm 3 5 cubic centimeters The approximate number of beans in the container is Number of beans 80 x 1000 cubic

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