121. Sea And Sky: Black Holes This is because black holes challenge the very foundation of the physical laws we tend to hold dear hear on Earth. Anatomy of a Black Hole. http://www.seasky.org/cosmic/sky7a10.html

Return to The Sky Return to The Cosmos Return to Cosmic Wonders Black Holes A Hole in Space Recipe for a Monster Anatomy of a Black Hole Stalking the Unseen A Hole in Space Recipe for a Monster Anatomy of a Black Hole Stalking the Unseen

122. BBC - Science & Nature - Space - Time Travel Gravity, black holes, singularity and mini wormholes. http://www.bbc.co.uk/science/space/exploration/timetravel/index.shtml

@import url('/includes/tbenh.css') ; Home TV Radio Talk ... A-Z Index MONDAY 7th June 2004 Text only Animals Prehistoric Life Genes ... BBC Homepage In Space Solar System My space Play space ... Help Like this page? Send it to a friend! You are here: BBC Space Exploration TIME TRAVEL Shaping the Future by Neil Johnson The idea of travelling forward into the future or back into the past has always fascinated science fiction writers. The 'grandfather paradox' is the argument many people use to suggest that time travel is impossible. What if you went back in time and prevented your grandfather from meeting your grandmother so that your mother was never born? Then you would never have been born... and so on. Until very recently such arguments led most scientists to believe that time travel could never exist outside science fiction. But amazingly, some interpretations of the weirdness of the quantum world now suggest that time travel is possible - at least in theory. Gravity and black holes Einstein's theory of relativity brought space and time together in a single, four-dimensional arrangement that he called spacetime. We know that we can travel forwards, backwards and sideways in space, so why not forwards and backwards in time? Four dimensions are difficult to imagine, so physicists usually suggest you think of spacetime as a rubber sheet stretched out flat. If there are no large masses around, the sheet stays flat, and so any object placed on it will move around in straight lines. But a large mass, such as the

123. 300 Black Hole Links http//antwrp.gsfc.nasa.gov/apod/lib/black_holes.html Astronomy Picture of the Day Index Stars black holes Archive Index Search Glossary Today s http://www.mysteries-megasite.com/main/bigsearch/blackhole.html

124. Black Holes Devour People - PRAVDA.Ru PRAVDA.Ru will hear you! black holes Devour People. 04/26/2004 1406. There are scores of such black holes on Earth, and people frequently get in them. http://english.pravda.ru/science/19/94/377/12624_Holes.html

var zflag_nid="305"; var zflag_cid="98/1"; var zflag_sid="56"; var zflag_width="1"; var zflag_height="1"; var zflag_sz="15"; Photo Reports: Weapons of victory: Russia's military aviation. Aviation history in photos Miss Universe Beauty Contest: gallery of all girls. Front page ... Services Latest news Three Europe's poorest countries Most Russians assign priority to Russia's G8 membership Martian pioneers to stay childless? Putin to live in bungalow in Sea Island ... More>> Latest PRAVDA.Ru Forum Topics Pretzel illogic Gasoline Costs 5 Cents a Gallon in Iraq Thanks to US Taxpayers Selling to Poor, Stores Bill U.S. for Top Prices Edwards Annointed As Next U.S. President? ... More>> Search Search internet Search pravda.ru Subscribe Lists at Felist.Com Comments From PRAVDA.Ru Information Partners Headliner Statistic Say what you want! PRAVDA.Ru will hear you! "Black Holes" Devour People A group of 150 people disappeared within one minute Witnesses clearly saw that a glimmering cloud shrouded the people who entered a small valley. Then the foggy mass lifted off and disappeared in the blue carrying along the first battalion of the 5th Norfolk regiment of the British army - all soldiers to a man were gone... Vanished in a cloud The event which occurred on August 21, 1915, when an entire battalion was gone in the presence of other people, had been an official secret for over fifty years. Only in 1967 the documents containing the testimonies of twenty witnesses to this incident, which happened in the Southern Europe near Dardanelles, were made public. A long search for the vanished soldiers was mounted. But none of them had been found neither among the dead, nor among the POWs released by Turks after the war.

125. Do Black Holes Exist...? Science popularization article on black holes. http://www.freehomepages.com/pgostrov/e3.html

Do black holes exist...? The term ``black hole'' was coined by the astrophysicist John Wheeler in 1969 to describe a kind of astrophysical object. Since then, the expression has been used very often as a metaphor, usually inappropriately. These enigmatic objects have also become stars of science fiction literature, doubtless due to their suggestive names and their peculiar properties. For those are curious about this issue, they have probably run across mysterious funnels, time tunnels and other aberrations. Many so called science popularizing works, resemble fantastic stories, more than essays to explain what is basically a simple concept. But what are in the end, these dark portents of the heavens? Do they really exist? To try to clean the name of this creature a little bit, let's start by clarifying that the concept of black hole (but not its overused name) was first coined by the English physicist John Mitchell in 1783, more than two hundred years ago...! It can be said that towards the end of the seventeenth century, Isaac Newton brought sky and Earth together. Based on planet movement studies made by Tycho Brahe and Johannes Kepler, he deduced the existence of a force that made the Sun, the Earth, the Moon and everything contained in the cosmos attract towards one another. The same law that make planets move as they do, make us keep our feet on the ground, stopping us from being ejected to space.

126. CGWP Making Waves With Intermediate-Mass Black Holes This site requires JavaScript and Style Sheets enabled. Some content may not appear properly. Focus Session Making Waves with IntermediateMass black holes. http://cgwp.gravity.psu.edu/events/IMBH/imbh.shtml

127. 1st SPOT Cosmology References to cosmological sites featuring indepth coverage of issues like dark matter, black holes and symmetric theory. http://1st-spot.freeservers.com/topic_cosmology.html

1st SPOT Cosmology COSMOLOGY Astroweb Baryon Assymetry Black Holes Introduction to black holes, physics. Creation in Physical Cosmology Academic paper looks at the 'problem' of origins in modern cosmology Cosmology Today Cosmology A simple but comprehensive new Cosmology Dark Matter Energy Science Fundamental Cosmology A philosophical study of a basis of all cosmologies. General Relativity Around The World General Relativity And Cosmology Introduction To Cosmology Isaac Newton's New Physics ... Net Wright's Cosmology Tutorial an illustrated introductory guide to cosmology Personal Cosmology Planet Search Project Search For Et Yourself! Seti@home ... The Planetary Society The Planetary Society is a nonprofit organization founded in 1980 by Carl Sagan, Bruce Murray, and Louis Friedman to encourage the exploration of our solar system and the search for extraterrestrial life. The Symmetric Theory Though widely accepted as a paradigm, the Big-Bang Theory is on weakening empirical ground. The Vacuum Of Space INSTITUTIONS MIT Astrophysics Lawrence Livermore National Lab OBSERVATORIES Arecibo Observatory Big Ear Radio Observatory This Kraus-type radio telescope, larger than three football fields, was famous for the Wow! Signal and for the longest-running SETI project.

128. Black Holes Properties of black holes, What is a black hole like? Quantum mechanics turns black holes from cold, eternal objects into hot shrinking thermodynamics. http://superstringtheory.com/blackh/

The Official String Theory Web Site Black Holes Quiz yourself on the content of this section Some basic books for further reading Some advanced books for further reading What would happen if gravity were so strong that even light could not escape its pull? The answer to this question is the shocking and amazing object known as the black hole. basic advanced What is a black hole like? How were they first discovered? How do astronomers know if they're seeing one? basic advanced Quantum mechanics turns black holes from cold, eternal objects into hot shrinking thermodynamics. Physicists wondered: Is there a microscopic origin for black hole entropy? basic advanced Find out how and why string theory modifies the spacetime equations of Einstein. basic advanced Thanks to the string duality revolution of the early nineties, a microscopic derivation for black hole entropy has been discovered, at least in theory. basic advanced Previous Next ... Gravitational collapse!

129. StarChild: Black Holes What is a black hole and how do we know it exists?(for K4th graders) http://starchild.gsfc.nasa.gov/docs/StarChild/universe_level1/black_holes.html

Listen Black Holes Some scientists believe that there is a black hole in our very own Milky Way. Black holes were once massive stars that used up all their fuel . As they died out, they collapsed inward due to the pull of their own gravity . The gravity of a black hole is so powerful that not even light can escape its pull! Once any matter falls into a black hole, it disappears from the visible Universe It is very hard to see a black hole. Any object that gets too close to a black hole will be pulled inside it. We only know they are there because of the effects they have on other objects that are near them. Any object, whether some dust, or a star, or anything, that gets too close to a black hole will be pulled inside it. As the objects fall toward the black hole, they heat up and get very hot. Scientists can use special instruments to detect the heat the objects give off. That is how we know the black hole must be there. A Question How do we know that there really are black holes? Show me the Level 2 version of this page.

130. VLT Close To The Action c.moreover.com/click/here.pl?r151671940 black holesblack holes. Gabor Kunstatter Physics Department University of Winnipeg black holes; Einstein’s Gravity and black holes; Problems with Newton; What is Gravity? http://c.moreover.com/click/here.pl?x151671940

131. Physics Central Physics In Action - Black Holes History of black holes The existence of black holes was predicted well before the 20th century. When a star dies. Seeing black holes. Exploring the universe. http://www.physicscentral.com/action/action-01-2.html

In Physics in Action we take you to a frontier area of physics every week. After a short introduction to the basic physics involved, we give you a taste of the current reseach in the field. matters of state gravity waves far out planets whole grains ... physics in action archives What Happens to a Star When It Dies A star exists in a delicate balance between the crushing force of gravity, on the one hand, and the push of incredibly hot gases on the other. This balance exists as long as there is fuel for the fusion process that powers the star. What happens when the star runs out of fuel? Then, gravity collapses the star. The more massive the star, the more drastic the collapse and the more condensed the remaining object. a star about the size of the sun: The collapse produces enough pressure to squeeze atoms right out of existence, leaving electrons and nuclei packed tightly together in an object about the size of Earth. The result is called a white dwarf. a star six to eight times larger than the sun: Upon exhausting its nuclear fuel, a star this large undergoes a catastrophic explosion as a supernova. (See

132. Black Hole Conference black holes III will be a scholarly researchrelated conference focusing on the latest advances in the theoretical and mathematical aspects of black hole http://fermi.phys.ualberta.ca/~gravity/bh3conference/

Black Holes III will be a scholarly research-related conference focusing on the latest advances in the theoretical and mathematical aspects of black hole physics. It will pay special attention to such mathematically oriented problems as the string and M theory approach to black holes, numerical studies of black hole collisions and critical gravitational collapse, and exact solutions of Einstein's equations in higher and lower dimensions. This is the third conference in a series and is being held at the Kananaskis Inn and Conference Center, Kananaskis, Alberta. The previous two were held in Banff, Alberta (1997) and in Val Morin, Quebec (1999). Invited seakers include: Steve Carlip, Matthew Choptuik, Steve Fairhurst, Valeri Frolov, Jack Gegenberg, William Hiscock, Bei-lok Hu, Ted Jacobson, Gabor Kunstatter, Hans Kunzle, Garry Ludwig, Robert Mann, Richard Matzner, Don Page, Renaud Parentiani, Amanda Peet, Scott Tremaine and William Unruh. Click here to download the poster for the meeting.

133. Black Holes And Event Horizons - Ghosts Of Stars Find articles, information, and web sites about these theoretical cellestial objects, formed when a massive star collapses from its own gravity. http://space.about.com/cs/blackholes/index.htm

zJs=10 zJs=11 zJs=12 zJs=13 zc(5,'jsc',zJs,9999999,'') About Homework Help Space / Astronomy Home ... Featured Astronomy Image of the Week zau(256,152,145,'gob','http://z.about.com/5/ad/go.htm?gs='+gs,''); Multimedia Resources News - Current Events Stars Planets Galaxies Education - Astronomy/Space ... Help zau(256,138,125,'el','http://z.about.com/0/ip/417/0.htm','');w(xb+xb); Stay Current Subscribe to the About Space / Astronomy newsletter. Search Space / Astronomy Blackholes and Event Horizons Guide picks Submit Your Site Black Holes Guide Resources dealing with black holes, singularities, and event horizons. Includes images, articles, web links and more black holes information. Lots of great resources on black holes, the ghosts of stars, with more added weekly. Top Fictional Black Hole Movies What are Black Holes - where do Black Holes come from and how do stars fit in? Find the answers to these and other questions in the top ten Black Hole books. Top 10 Nonfiction Black Hole Books The idea of black holes was first theorized in the late eighteenth century. Black holes are still just a theory, but a very good theory. Now that astronomers have acquired evidence that theoretical white dwarfs and neutron stars really exist, the case for black holes has been strengthened. Discover more about these fascinating theoretical phenomena. Black Hole Images Images of black holes provided by the Hubble Space Telescope.

134. Look Down The Throat Of A Black Hole have used the Hubble Space Telescope to trace the spiraling path of galactic material, swirling toward what they believe are voracious black holes at their http://www.msnbc.com/news/385041.asp

The orangish picture focuses on the very center of the active galaxy Markarian 573. The image, which combines readings taken in visible and near-infrared light, traces a spiral of galactic dust with what scientists believe is a supermassive black hole at its center. Look down the throat of a black hole By Alan Boyle MSNBC A STEP FURTHER Pogge explained that starlight passes more easily through galactic dust in near-infrared wavelengths than in the visible wavelengths. Thus, by tinkering with the two views, the researchers could develop images that highlighted the dust patterns rather than the starlight. The researchers believe that inactive galaxies might be in equilibrium, with material cleared out at a safe distance from the central black hole. Pogge said it would take some kind of disturbance to set off a feeding spiral, perhaps a tidal encounter with another galaxy, or shock waves from a cosmic eruption. Here are some other black hole projects that have recently borne fruit, based on research reports: Astronomers at the University of Nottingham and the University of Birmingham in England have developed evidence that supermassive black holes at galactic centers gradually put on weight by consuming a steady diet of gas and stars.

135. Central Force With Java A JAVA applet to simulate orbits in four different central forces gravity, Yukawa, 1/R^4 and black holes http://www.astro.queensu.ca/~musgrave/cforce/

Central Force Motion with Java The applet below illustrates the orbits of particles in a variety of color-coded forces. (Your browser is not Java aware) Overview of this site Investigate the qualitative behaviour of orbits in different forces (gravity, Yukawa potential, Harmonic force (i.e. spring), 1/R force) See how effective potentials are used to find turning points of orbits in a central force and for black holes Use the OrbitApplet to try and change the orbit of a spaceship to intercept a target (your chance to "make it so") Learn something about Java by delving into the source code including Booch-like diagrams of the object heirarchy employed Central Force Central force refers to a force which always acts towards a fixed point (the center). As the above Applet demonstrates different central forces result in qualitativly different orbits. Some forces produce closed orbits, others a "spirograph" pattern. (The black hole is not described by a force per se see the black hole explanation).

136. BUBL LINK / 5:15 Internet Resources: Black Holes singularities. Also outlines the physical properties of black holes, and examines the connection between them and the theory of relativity. http://bubl.ac.uk/link/b/blackholes.htm

BUBL LINK / 5:15 Catalogue of Internet Resources Home Search Subject Menus A-Z ... About Black holes A-Z Index Titles Descriptions Astronomy Information Leaflets Black Holes FAQ Exploring Gravity High Energy Astrophysics Science Archive Research Center ... Virtual Trips to Black Holes and Neutron Stars Page last updated: 17 March 2003 Comments: bubl@bubl.ac.uk Astronomy Information Leaflets Text from a series of educational leaflets covering a wide range of topics in astronomy and cosmology. Educational use of the information by private individuals or schools is encouraged. Author: Royal Greenwich Observatory Subjects: astronomy education, black holes, cosmology, pulsars, satellites, spectroscopy, stars DeweyClass: ResourceType: document collection Location: uk Last checked: url=12676/">Black Hole: The Death of a Star Provides an introduction to the black hole phenomena, including the formation of singularities. Also outlines the physical properties of black holes, and examines the connection between them and the theory of relativity. Author: Loi Hui Min, Cuandi and Tan Keng Kiang.

137. Black Holes: General Information Learn about the amazing phenomenon that is a black hole. http://www.geocities.com/blackholeinfo/

138. The Astrophysical Journal Founded in 1895 and published by the American Astronomical Society. It is devoted to recent developments, discoveries, and theories in astronomy and astrophysics. Quasars, pulsars, neutron stars, black holes, solar and stellar magnetic fields, Xrays, and interstellar matter. In addition, videos that complement specific issues are periodically available. http://www.journals.uchicago.edu/ApJ/

This web site was designed using frames. If your browser does not support frames, you must upgrade to either or Internet Explorer 3.0 (or later)

139. Blackh black holes. A massive star universe. It has even been speculated that black holes could be pathways into other universes. Gravity is http://www.pbs.org/wnet/hawking/strange/html/strange_blackh.html

BLACK HOLES A massive star starts to collapse when it exhausts its nuclear fuel and can no longer counteract the inward pull of gravity. The crushing weight of the star’s overlying layers implodes the core, and the star digs deeper into the fabric of space-time. Although the star remains barely visible, its light now has a difficult time climbing out of the enormous gravity of the still-collapsing core. The star passes through its event horizon and disappears from our universe, forming a singularity of infinite density. Singularities Stephen Hawking Do Black Holes Really Exist? Can Anything Escape from a Black Hole? P ile enough matter into a small enough volume and its gravitational pull will grow so strong that nothing can escape from it. That includes light, which travels at the absolute cosmic speed limit of 186,000 miles per second. In a stroke of descriptive genius, physicist John Wheeler named these objects “black holes.” The radius of a black hole is called the event horizon because it marks the edge beyond which light cannot escape, so any event taking place inside the event horizon can never be glimpsed from outside—in effect, the inside of the black hole is cut off from our universe. It has even been speculated that black holes could be pathways into other universes. Gravity is so strong at the center of a black hole, that even Einstein’s gravitational laws must break down. The theory that governs the incredibly dense matter and strong gravitational fields at the center of a black hole is not yet known.”

140. Wired News: Black Holes And Space Travel black holes and Space Travel. The idea that spaceships might zip across the universe using black holes as a highspeed portal is a well-worn sci-fi cliché. http://www.wired.com/news/technology/0,1282,58359,00.html?tw=wn_story_related

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z

Page 7     121-140 of 172    Back | 1  | 2  | 3  | 4  | 5  | 6  | 7  | 8  | 9  | Next 20