| Interstellar Phenomens |
Stellarer Cluster (Deltaquadrant): | Recent surveys of star-forming regions have shown that most stars, and probably all massive stars, are born in dense stellar clusters. The mechanism by which a molecular cloud fragments to form several hundred to thousands of individual stars has remained elusive. Here, we use a numerical simulation to follow the fragmentation of a turbulent molecular cloud, and the subsequent formation and early evolution of a stellar cluster containing more than 400 stars. We show that the stellar cluster forms through the hierarchical fragmentation of a turbulent molecular cloud. This leads to the formation of many small subclusters, which interact and merge to form the final stellar cluster. The hierarchical nature of the cluster formation has serious implications in terms of the properties of the new-born stars. The higher number-density of stars in subclusters, compared to a more uniform distribution arising from a monolithic formation, results in closer and more frequent dynamical interactions. Such close interactions can truncate circumstellar discs, harden existing binaries and potentially liberate a population of planets. We estimate that at least one-third of all stars, and most massive stars, suffer such disruptive interactions. (credit:Monthly Notice of the Royal Astronomical Society,Volume 343 Issue 2 Page 413 - August 2003) | |
Flash Plasmastorm: | recorded by Voyager in the delta Quadrant on planet named New Earth | |
Gravimetric Distortion: | Gravimetric fluctuations sometimes accompany interruptions in the normal folow of space and tim. Spatial distortion phenomena can cause a wide range of problems. | |
Quantum Singularität: | | |
Inversion Nebula: | interstellar gas cloud, filled with highlz unstable plasma strings. Normally they are so unstable, that they burn themsselfs out in a very short time. Inversion Nebula's can have very colorfull spectra. | |
Nekrit Expanse Region: | a vast reagion in the delta quadrant. It is filled with an unknown form of interstellar dust clouds and plasma storms. The Necrit expanse region is so large and unstable, that until now it wasn't even cartiographed. Recorded by Voyager in 2373 | |
Gravitation Ellipse: | A rare phenomen, which travels in subspace and emerge periodically in real space. It is drawn by shieldpolarity. | |
Nexus: | The entrance into the Nexus, which is in fact a nonlinear temporal phenomenon, was a temporal flux energy ribbon which crossed the Milky Way Galaxy every 39.2 years. The Nexus itself, once you are inside, causes reality to shape itself according to personal desires. Time itself has no meaning and any reality you want becomes fact. | |
| pictures taken on Terra in the 20th and 21th century | ||
Sombrero Galaxy: | The famous Sombrero galaxy (M104) is a bright nearby spiral galaxy. The prominent dust lane and halo of stars and globular clusters give this galaxy its name. Something very energetic is going on in the Sombrero's center, as much X-ray light has been detected from it. This X-ray emission coupled with unusually high central stellar velocities cause many astronomers to speculate that a black hole lies at the Sombrero's center - a black hole a billion times the mass of our Sun. (credit:NOAO/AURA/NSF) | |
Pferdekopfnebel: | One of the most identifiable nebulae in the sky, the Horsehead Nebula in Orion, is part of a large, dark, molecular cloud. Also known as Barnard 33, the unusual shape was first discovered on a photographic plate in the late 1800s. The red glow originates from hydrogen gas predominantly behind the nebula, ionized by the nearby bright star Sigma Orionis. The darkness of the Horsehead is caused mostly by thick dust, although the lower part of the Horsehead's neck casts a shadow to the left. Streams of gas leaving the nebula are funneled by a strong magnetic field. Bright spots in the Horsehead Nebula's base are young stars just in the process of forming. Light takes about 1500 years to reach us from the Horsehead Nebula. The above image was taken with the 0.9-meter telescope at Kitt Peak National Observatory. (Terra) (credit:NOAO/AURA/NSF) | |
dark molecular cloud Barnard 68: | Where did all the stars go? What used to be considered a hole in the sky is now known to astronomers as a dark molecular cloud. Here, a high concentration of dust and molecular gas absorb practically all the visible light emitted from background stars. The eerily dark surroundings help make the interiors of molecular clouds some of the coldest and most isolated places in the universe. One of the most notable of these dark absorption nebulae is a cloud toward the constellation Ophiuchus known as Barnard 68, pictured above. That no stars are visible in the center indicates that Barnard 68 is relatively nearby, with measurements placing it about 500 light-years away and half a light-year across. It is not known exactly how molecular clouds like Barnard 68 form, but it is known that these clouds are themselves likely places for new stars to form. It is possible to look right through the cloud in infrared light (credit:NOAO/AURA/NSF) | |
cats eye nebula: | Three thousand light years away, a dying star throws off shells of glowing gas. This Hubble Space Telescope image reveals "The Cat's Eye Nebula" to be one of the most complex "planetary nebulae" known. In fact, the features seen in this image are so complex that astronomers suspect the visible central star may actually be a double star system. The term planetary nebula, used to describe this general class of objects, is misleading. Although these objects may appear round and planet-like in small telescopes, high resolution images reveal them to be stars surrounded by cocoons of gas blown off in the late stages of evolution. Image Taken in the year 1995 Terra (credit:NOAO/AURA/NSF) | |
Lagoon Nebula: | The bright Lagoon Nebula is home to a diverse array of astronomical objects. Particularly interesting sources include a bright open cluster of stars and several energetic star-forming regions. When viewed by eye, cluster light is dominated by an overall red glow that is caused by luminous hydrogen gas, while the dark filaments are caused by absorption by dense lanes of dust. The above picture, from the Curtis-Schmidt Telescope, however, shows the nebula's emission in three exact colors specifically emitted by hydrogen, oxygen, and sulfur. The Lagoon Nebula, also known as M8 and NGC 6523, lies about 5000 light-years away. The Lagoon Nebula can be located with binoculars in the constellation of Sagittarius spanning a region over three times the diameter of a full Moon. (Credit: R. Barba, N. Morrell et al. (UNLP), CTIO, NOAO, NSF 2002) | |
Rho Ophiuchi Wolken: | The many spectacular colors of the Rho Ophiuchi (oh'-fee-yu-kee) clouds highlight the many processes that occur there. The blue regions shine primarily by reflected light. Blue light from the star Rho Ophiuchi and nearby stars reflects more efficiently off this portion of the nebula than red light. The Earth's daytime sky appears blue for the same reason. The red and yellow regions shine primarily because of emission from the nebula's atomic and molecular gas. Light from nearby blue stars - more energetic than the bright star Antares - knocks electrons away from the gas, which then shines when the electrons recombine with the gas. The dark regions are caused by dust grains - born in young stellar atmospheres - which effectively block light emitted behind them. The Rho Ophiuchi star clouds, well in front of the globular cluster M4 visible above on far lower left, are even more colorful than humans can see - the clouds emits light in every wavelength band from the radio to the gamma-ray. (Credit: Photograph made from plates taken with the UK Schmidt Telescope. Color photography by David Malin. Copyright: Royal Observatory, Edinburgh, Anglo-Australian Observatory 1996) | |
Cygnus Loop Supernova Shockwave: | 15,000 years ago a star in the constellation of Cygnus exploded. This picture shows a portion of a shockwave from this supernova explosion still expanding past nearby stars. The collision of this gaseous shockwave with a stationary gas cloud has heated the gas causing it to glow in a spectacular array of colors, known as the Cygnus Loop. This picture was taken with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope. (Credit: NASA, HST, WFPC2, Jeff Hester 1995) | |
Eta Carinae: | The star Eta Carinae, at the center of the photo, will likely destroy itself in a spectacular explosion in a few million years - or sooner! Currently it is one of the brightest, most massive, and least stable stars known. Much of the gas in this Hubble Space Telescope photograph was blown off the star itself. Some of these gas clouds are similar in size to our solar system. Astronomers cannot yet fully explain the motions of the surrounding nebula, and continue to study this system. (Credit: NASA, HST, WFPC2, J. Hester (ASU)1995 ) | |
Orion Nebula: | The Great Nebula in Orion, an immense, nearby starbirth region, is arguably the most famous of all astronomical nebulae. The Orion Nebula, also known as M42, is shown above through ultraviolet and blue filters augmented with three exact colors specifically emitted by hydrogen, oxygen, and sulfur. In addition to housing a bright open cluster of stars known as the Trapezium, the Orion Nebula contains many stellar nurseries. These nurseries contain glowing gas, hot young stars, proplyds, and stellar jets spewing material at high speeds. Many of the filamentary structures visible in this image are actually shock waves - fronts where fast moving material encounters slow moving gas. The Orion Nebula spans about 40 light years and is located about 1500 light years away in the same spiral arm of our Galaxy as the Sun. (Credit: NASA, Hubble Space Telescope 1995 ) | |
HH 47 Star Jet: | The star masked by a dust cloud at the left of the above photo is expelling an energetic beam of charged particles into interstellar space. This jet, moving from left to right, has burrowed through much interstellar material, and now expands out into the interstellar space. Although jet particles move at nearly three hundred kilometers per second , we still do not see any daily movement because of the enormous distances involved. In fact, the jet is trillions of kilometers long. This stellar jet occurs in a system called HH-47 which is located near the edge of the Gum Nebula. (Credit: NASA, HST, WFPC 2, J. Morse 1995) | |
Cocoon of a New White Twarf: | Like a butterfly, a white dwarf star begins its life by casting off a cocoon that enclosed its former self. In this analogy, however, the Sun would be a caterpillar and the ejected shell of gas would become the prettiest of all! The above cocoon, the planetary nebula designated NGC 2440, contains one of the hottest white dwarf stars known. The white dwarf can be seen as the bright dot near the photo's center. Our Sun will eventually become a "white dwarf butterfly", but not for another 5 billion years. The above false color image and was post-processed by Forrest Hamilton. (Credit: H. Bond (STScI), R. Ciardullo (PSU), WFPC2, HST, NASA) | |
Wings of a Butterfly Nebula | Are stars better appreciated for their art after they die? Actually, stars usually create their most artistic displays as they die. In the case of low-mass stars like our Sun and M2-9 pictured above, the stars transform themselves from normal stars to white dwarfs by casting off their outer gaseous envelopes. The expended gas frequently forms an impressive display called a planetary nebula that fades gradually over thousand of years. M2-9, a butterfly planetary nebula 2100 light-years away shown in representative colors, has wings that tell a strange but incomplete tale. In the center, two stars orbit inside a gaseous disk 10 times the orbit of Pluto. The expelled envelope of the dying star breaks out from the disk creating the bipolar appearance. Much remains unknown about the physical processes that cause planetary nebulae. (Credit: B. Balick (U. Washington) etp al., WFPC2, HST, NASA 12/1997) | |
Gaseous Pillars M16: | Explanation: Newborn stars are forming in the Eagle Nebula. This image, taken with the Hubble Space Telescope in 1995, shows evaporating gaseous globules (EGGs) emerging from pillars of molecular hydrogen gas and dust. The giant pillars are light years in length and are so dense that interior gas contracts gravitationally to form stars. At each pillars' end, the intense radiation of bright young stars causes low density material to boil away, leaving stellar nurseries of dense EGGs exposed. The Eagle Nebula, associated with the open star cluster M16, lies about 7000 light years away. (Credit: Credit: J. Hester, P. Scowen (ASU), HST, NASA 11/1995) | |
Wings of a Butterfly Nebula: | The Rosette Nebula is a large emission nebula located 3000 light-years away. The great abundance of hydrogen gas gives NGC 2237 its red color in most photographs. The wind from the open cluster of stars known as NGC 2244 has cleared a hole in the nebula's center. The above photograph, however, was taken in the light emitted by three elements of the gas ionized by the energetic central stars. Here green light originating from oxygen and blue light originating from sulfur supplements the red from hydrogen. Filaments of dark dust lace run through the nebula's gases. The origin of recently observed fast-moving molecular knots in the Rosette Nebula remains under investigation. (Credit: T. A. Rector, B. Wolpa, M. Hanna (AURA/NOAO/NSF) 12/1997 | |
North American Nebula: | Explanation: Here's a familiar shape in an unfamiliar location! This emission nebula is famous partly because it resembles Earth's North American Continent. To the right of the North America Nebula is a less luminous Pelican Nebula. Let's be grateful that pelicans aren't really that large! The two emission nebula are located about 1500 light years away and are separated by a dark absorption cloud. The nebulae can be seen without a telescope from a dark location. Look for a small nebular patch north-east of Deneb in the constellation of Cygnus. It is still unknown which star or stars ionize the red-glowing hydrogen gas. (Credit and Copyright: Dominique Dierick and Dirk De la Marche) | |
Hydrogen Trifid: | Clouds of glowing hydrogen gas mingle with dark dust lanes in the Trifid Nebula, a star forming region in the constellation Sagittarius. In this and other similar emission nebulae, energetic ultraviolet light from an embedded hot young star strips electrons from the surrounding hydrogen atoms. As the electrons and atoms recombine they emit longer wavelength, lower energy light in a well known characteristic pattern of bright spectral lines. At visible wavelengths, the strongest emission line in this pattern is in the red part of the spectrum and is known as "Hydrogen-alpha" or just H-alpha. This image of the nebula was taken using a filter to select only light near the H-alpha wavelength. It shows those regions with substantial emission from atomic hydrogen. The relative strength of this emission can trace the densities of atoms within the gas cloud. (Credit and Copyright: David McDavid ( Limber Observatory) | |
The Witch Head Nebula | Double, double toil and trouble; Fire burn, and cauldron bubble ... Maybe Macbeth should have consulted the Witch Head Nebula. This suggestively shaped reflection nebula is associated with the bright star Rigel in the constellation Orion. More formally known as IC 2118, the Witch Head Nebula glows primarily by light reflected from Rigel. Rigel is located about one photo-width off the image to the right. Fine dust in the nebula reflects the light. The blue color is caused not only by Rigel's blue color but because the dust grains reflect blue light more efficiently than red. The same physical process causes Earth's daytime sky to appear blue, although the scatterers here are molecules of nitrogen and oxygen. The nebula lies about 1000 light-years away. (Credit: G. Greaney ) | |
The Crab Nebula from VLT | The Crab Nebula, filled with mysterious filaments, is the result of a star that was seen to explode in 1054 AD. This spectacular supernova explosion was recorded by Chinese and (quite probably) Anasazi Indian astronomers. The filaments are mysterious because they appear to have less mass than expelled in the original supernova and higher speed than expected from a free explosion. In the above picture taken recently from a Very Large Telescope, the color indicates what is happening to the electrons in different parts of the Crab Nebula. Red indicates the electrons are recombining with protons to form neutral hydrogen, while blue indicates the electrons are whirling around the magnetic field of the inner nebula. In the nebula's very center lies a pulsar: a neutron star rotating, in this case, 30 times a second. (Credit: FORS Team, 8.2-meter VLT, ESO ) | |
Disorder in Stephan's Quintet | What are four closely grouped galaxies doing in this image? The grouping composes a majority of the large galaxies in Stephan's Quintet, with the fifth prominent galaxy located off the above image to the lower right. Three of these four galaxies show nearly the same redshift, indicating that they reside at the same distance from us. These three galaxies are in the midst a titanic collision, each ripping the others apart with gravitational tidal forces. The large bluish spiral below and left of center is a foreground galaxy much closer than the others and hence not involved in the cosmic battle. Most of Stephan's Quintet lies about 300 million light-years away towards the constellation of Pegasus. (Credit: Jane C. Charlton (Penn State) et al., HST, ESA, NASA 11/1995) | |
Closeup of Antennae Galaxy Collision | It's a clash of the titans. Two galaxies are squaring off in Corvus and here are the latest pictures. When two galaxies collide, however, the stars that compose them usually do not. This is because galaxies are mostly empty space and, however bright, stars only take up only a small amount of that space. But during the slow, hundred million year collision, one galaxy can rip the other apart gravitationally, and dust and gas common to both galaxies does collide. In the above wreckage, dark dust pillars mark massive molecular clouds, which are being compressed during the galactic encounter, causing the rapid birth of millions of stars. (Credit: B. Whitmore (STScI), F. Schweizer (DTM), NASA ) | |
M31: The Andromeda Galaxy: | Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. The several distinct stars that surround Andromeda's image are actually stars in our Galaxy that are well in front of the background object. Andromeda is frequently referred to as M31 since it is the 31st object on Messier's list of diffuse sky objects. M31 is so distant it takes about two million years for light to reach us from there. Much about M31 remains unknown, including why the center contains two nuclei. (Credit: Credit: J. Hester, P. Scowen (ASU), HST, NASA) | |
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