Crab Nebula
Looking up at the night sky you see stars lying on a never-ending dark blanket. It is within this “blanket”, called the interstellar medium, that new stars are formed. The interstellar medium consists of 99% gas and about 1% dust particles. Hydrogen is the predominant gas in both atomic and molecular forms. While being the place where stars are born, the interstellar medium also creates beautiful nebulae. A reflection nebula is created when light from a nearby star reflects from the dust particles in the interstellar medium. There are two main types of nebulae and two other descriptions of what happens to the light that comes from nearby stars.
One of the main types of nebulae is called a reflection nebula. The particles around stars are about the same size as the wavelength of visible light and therefore they are able to reflect the visible light being emitted from the nearby star. However, most of the time these clouds of dust have a bluish color to them and that is due to the fact that the particles are at about the same size as the blue wavelengths and it is harder for them to interact with the longer red or orange wavelengths. The best reflections nebulae come around stars that are cooler than 25000 K. Another main type of nebula is an emission nebula and this type derives its light from the UV radiation being emitted from a nearby star. The light from the starts exites atoms in the dust cloud which in turn emit light. . When describing what happens to light coming from a star there are two things that refer to it. One would be extinction and this happens when the dust cloud around the star is so dense that the light cannot pass through it and it appears as if the light just stops or makes the star appear dimmer than it really is. Another one would be reddening and this happens when the dust particles in the interstellar medium pass the longer red or orange wavelengths. This process gives the clouds a reddish color and overpowers the blues, greens , and violets.
A supernova remnant is a cloud of gas created in the explosion of a star as a supernova. Located 6,300 light years away, the Crab Nebula (M1) is one of the most famous supernova remnants and is one of only a few historically observed supernovae in the Milky Way Galaxy. It is specifically located at right ascension 5 hour...
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... our own sun (In Context).
Some neutron stars emit radio waves, light, and other forms of radiation that appear to pulse on and off like a lighthouse beacon. Called pulsars, they only appear to turn radio waves on and off because the star is spinning. We can only pick up the radio waves when the pulsar’s beam sweeps across Earth. Their rapid rotation makes them powerful electric generators, trapping and emitting charged particles though space as radio waves. It can charge these particles up to millions of volts. The Crab pulsar, produces enough energy to power the nebula and make it expand (History).
Because a pulsar’s energy output lights up and expands the nebula around it, it loses energy from the rotation, causing it to spin slower over time. However, the rate of loss is so minimal that it will take about 10,000 years for the pulsar to slow to even half of its current speed. As time goes on, the Crab’s pulses will become less and less intense, and its X-Ray emissions will eventually end. The nebula itself will disappear after only a few thousand years, leaving only the radio pulsar to beam every few seconds (History).
These stars are very large and therefore have very big surface areas. These large surface areas give off large amounts of light and this makes the stars bright. Most of these stars are known as red giants. Some are so large however that they are referred to as supergiants. Red giants have a temperature of about 3,500 degrees Kelvin and an absolute magnitude of around 0. Supergiants have a temperature of around 3,000 degrees Kelvin and an absolute magnitude of about -7.
Messier 8, nicknamed the Lagoon Nebula is an interstellar cloud located in Sagittarius, discovered by John Flamsteed in 1680. It is one of the few nebulae that can be seen by the naked eye. It was given its nickname by Agnes
... only be seen via X-rays. Hotter areas can be seen more clearly than the cooler areas. Lastly, there are things called Accretion stars. Sometimes, debris from other material around the pulsar will be pulled into orbit around it. The debris will become superheated in the intense energy of the neutron star. The material becomes hot enough to radiate x-rays in addition to the radio signals being emitted by the pulsar itself.
This accretion disk heats up through friction to such high temperatures that it emits X-rays. And also there are some X-ray sources which have all the properties described above. Unfortunately, it is impossible to distinguish between a black hole and a neutron star unless we can prove that the mass of the unseen component is too great for a neutron star. Strong evidence was found by Royal Greenwich Observatory astronomers that one of these sources called Cyg X-1 (which means the first X-ray source discovered in the constellation of Cygnus) does indeed contain a black hole. It is possible for a star to be swallowed by the black hole....
Stars explode at the end of their lifetime, sometimes when they explode the stars leave a remnant of gasses and, dust behind. What the gasses come together to form depend on the size of the remnant. If the remnant is less than 1.4 solar masses it will become a white dwarf, a hot dead star that is not bright enough to shine. If the remnant is roughly 1.4 solar masses, it will collapse. “The protons and electrons will be squashed together, and their elementary particles will recombine to form neutrons”. What results from this reaction is called a neut...
Nebula that was destroyed after it’s sun went supernova. Troubled by his findings, the priest
The Orion Nebula is one of the closest stellar regions to the Earth. Using parallax measurements, it has been estimated that this nebula is only 1,500 light years away. In addition, the Orion Nebula is a relatively young star cluster, with an approximate age of less than one million years. It has even been speculated that some of the younger stars within the cluster are only 300,000 years old.
Solar nebula is a rotating flattened disk of gas and dust in which the outer part of the disk became planets while the center bulge part became the sun. Its inner part is hot, which is heated by a young sun and due to the impact of the gas falling on the disk during its collapse. However, the outer part is cold and far below the freezing point of water. In the solar nebula, the process of condensation occurs after enough cooling of solar nebula and results in the formation into a disk. Condensation is a process of cooling the gas and its molecules stick together to form liquid or solid particles. Therefore, condensation is the change from gas to liquid. In this process, the gas must cool below a critical temperature. Accretion is the process in which the tiny condensed particles from the nebula begin to stick together to form bigger pieces. Solar nebular theory explains the formation of the solar system. In the solar nebula, tiny grains stuck together and created bigger grains that grew into clumps, possibly held together by electrical forces similar to those that make lint stick to your clothes. Subsequent collisions, if not too violent, allowed these smaller particles to grow into objects ranging in size from millimeters to kilometers. These larger objects are called planetesimals. As planetesimals moved within the disk and collide with one another, planets formed. Because astronomers have no direct way to observe how the Solar System formed, they rely heavily on computer simulations to study that remote time. Computer simulations try to solve Newton’s laws of motion for the complex mix of dust and gas that we believe made up the solar nebula. Merging of the planetesimals increased their mass and thus their gravitational attraction. That, in turn, helped them grow even more massive by drawing planetesimals into clumps or rings around the sun. The process of planets building undergoes consumption of most of the planetesimals. Some survived planetesimals form small moons, asteroids, and comets. The leftover Rocky planetesimals that remained between Jupiter and Mars were stirred by Jupiter’s gravitational force. Therefore, these Rocky planetesimals are unable to assemble into a planet. These planetesimals are known as asteroids. Formation of solar system is explained by solar nebular theory. A rotating flat disk with center bulge is the solar nebula. The outer part of the disk becomes planets and the center bulge becomes the sun.
When itBetelgeuse cannot fuse anymore anything over iron, the star will not have enough energy to make heat. Eventually, the core will collapse. When Betelgeuse collapses, it is so strong and powerful that it causes the outer layers to rebound. With the rebound it will have an explosion, which is called a Supernova (Type two). The explosion has so much energy and power that the temperature becomes really hot. The temperature is so hot that it can use the fusion process much heavier than iron. The elements that were given off from the explosion are sent throughout space and are now new nebula. When the Supernova is done, it has left behind a star called a Neutron star. They form when atoms of the core of a dead star are crushed together and the end result produces neutrons. The neutrons are with electrons that are degenerate on the surface. Many Neutron stars have magnetic fields and they give off strong waves of radiation from their poles. These types of Neutron Stars are known as Pulsars.
A star begins as nothing more than a very light distribution of interstellar gases and dust particles over a distance of a few dozen lightyears. Although there is extremely low pressure existing between stars, this distribution of gas exists instead of a true vacuum. If the density of gas becomes larger than .1 particles per cubic centimeter, the interstellar gas grows unstable. Any small deviation in density, and because it is impossible to have a perfectly even distribution in these clouds this is something that will naturally occur, and the area begins to contract. This happens because between about .1 and 1 particles per cubic centimeter, pressure gains an inverse relationship with density. This causes internal pressure to decrease with increasing density, which because of the higher external pressure, causes the density to continue to increase. This causes the gas in the interstellar medium to spontaneously collect into denser clouds. The denser clouds will contain molecular hydrogen (H2) and interstellar dust particles including carbon compounds, silicates, and small impure ice crystals. Also, within these clouds, there are 2 types of zones. There are H I zones, which contain neutral hydrogen and often have a temperature around 100 Kelvin (K), and there are H II zones, which contain ionized hydrogen and have a temperature around 10,000 K. The ionized hydrogen absorbs ultraviolet light from it’s environment and retransmits it as visible and infrared light. These clouds, visible to the human eye, have been named nebulae. The density in these nebulae is usually about 10 atoms per cubic centimeter. In brighter nebulae, there exists densities of up to several thousand atoms per cubic centimete...
If the nebula is dense enough, certain regions of it will begin to gravitationally collapse after being disturbed. As it collapses the particles begin to move more rapidly, which on a molecular level is actually heat, and photons are emitted that drive off the remaining dust and gas. Once the cloud has collapsed enough to cause the core temperature to reach ten-million degrees Celsius, nuclear fusion starts in its core and this ball of gas and dust is now a star. It begins its life as a main sequence star and little does it know its entire life has already been predetermined.
The Big Bang, the alpha of existence for the building blocks of stars, happened approximately fourteen billion years ago. The elements produced by the big bang consisted of hydrogen and helium with trace amounts of lithium. Hydrogen and helium are the essential structure which build stars. Within these early stars, heavier elements were slowly formed through a process known as nucleosynthesis. Nucleosythesis is the process of creating new atomic nuclei from pre-existing nucleons. As the stars expel their contents, be it going supernova, solar winds, or solar explosions, these heavier elements along with other “star stuff” are ejected into the interstellar medium where they will later be recycled into another star. This physical process of galactic recycling is how or solar system's mass came to contain 2% of these heavier elements.
After a supernova, the core is likely to travel someplace else within space. When the core is less size than about 5 solar masses, the neutrons will halt the collapse of the star. This will create a Neutron Star. Neutron stars are observed as pulsars or X-ray binaries. When the core is very large, nothing that h...
The idea behind the Solar Nebular Hypothesis is that the solar system was condensed from an enormous cloud of hydrogen, helium, and a few other elements and rocks. Around five billion years this cloud of materials began to spin and contract together into a disk shape under their own gravitational forces. The particles started combined together, protoplanets, to eventually form planets. A great mass of the material eventually began to form together, protosun, and make up the sun.
The Sun, in turn, is moving in an undulating orbit around the centre of the MIlky Way at 800,000 km/h (ka-boom would be 15 TJ - about a 3.5 kiloton baby nuke), which in turn is moving with the Local Group towards the Virgo Cluster, which in turn...... and so on and so on.