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Thread: Weird

  1. #1 Weird 
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    There are some strange and exotic animals in the cosmic zoo, many taking the form of stellar remnants.

    NEUTRON STAR - Neutron stars are remnants of supernova explosions. When the cores of these stars collapse, their protons and electrons combine to form neutrons. Neutron stars are dense. A spoonful would weigh a billion tons on earth.

    PULSAR - A pulsar is a neutron star that rotates. It "pulses" like a lighthouse. A pulsar lies in the Crab Nebula, a supernova remnant from 1054 A.D. Pulsars were discovered by Jocelyn Bell.

    SUPERNOVA - A supernova is a massive star blowing up. Enormous energy is released. Heavy elements are created by the explosion and distributed through interstellar space. The elements in our bodies came from supernovas. Supernovas in our own galaxy occur on the average of one per century. Tycho Brahe's star in 1572 was a supernova. One was discovered in 1987 in the Large Magellanic Cloud and given the name SN 1987A.

    EXOPLANETS - 851 exoplanets have been confirmed as of November, 2012. These are planets outside of our solar system, orbiting stars other than our own. Most exoplanets found thus far are like Jupiter although earth-like planets are being exposed as techniques improve. Indirect methods are used. The most successful are the radial velocity and transit methods. Astronomers measure gravitational influence on a parent star as well as a star's brightness as a planet passes in front of it. They look for planets in the habitable zones, ones that may have water and be able to support life. The Kepler Space Telescope has searched for exoplanets since 2009. There may be billions in the Milky Way, many supporting simple life. There may be a few advanced civilizations with the technology needed to send signals in search of other intelligent life. Perhaps we should take the advice of Stephen Hawking and lay low.

    DARK MATTER - Dark matter is believed to make up 25% of the universe. Normal matter accounts for 5%. Astronomers think dark matter is real because of its effect on normal matter. There are many theories as to what it consists of. Dark matter tries to hold the universe together while dark energy tries to pull it apart.

    DARK ENERGY - When the expansion of the universe was found to be accelerating, the mysterious force responsible was given the name "dark energy." Dark energy is driving galaxies apart at a greater and greater speed. It overtook gravity to become the dominant force. Dark energy is said to make up 70% of the universe.

    BLACK HOLE - A black hole is a dead star whose gravity is so strong that even light cannot escape. Black holes are invisible. Their gravity is strong because their mass has collapsed into an infinitely small space. Black holes come in all sizes, the largest being "supermassive." Large galaxies have supermassive black holes at their centers, and there is probably one at the center of the Milky Way. Black holes form when large stars collapse. Scientists detect them by their gravitational affect on the stars around them. An "event horizon" is the boundary beyond which an object cannot escape. NASA's Chandra X-ray telescope has shown black holes to be common.

    WHITE HOLE - White holes do not exist in nature. They exist hypothetically in General Relativity as opposites of black holes. Light entering a black hole can never escape. The reverse applies to white holes. Nothing can enter a white hole, yet light can escape. Einstein's influence on cosmology has been profound.

    QUASARS - Quasars are the cores of young, energetic galaxies falling into black holes. Tremendous radiation is emitted. No larger than our solar system, quasars outshine entire galaxies. They are far away, up to 12 billion light-years. Astronomers get a glimpse of the early universe.

    COSMIC RAYS - Cosmic rays are high-energy particles from other parts of the galaxy. They are pieces of atoms, most likely remnants of supernovas. Cosmic rays travel close to the speed of light.

    GAMMA RAY BURST - A GBR is a brilliant flash of energy. Our eyes do not see gamma rays, nor can they penetrate our atmosphere. We know of their presence via satellites. GRBs come from supernovas and black holes in other galaxies.

    ANTIMATTER - Small amounts of antimatter exist in the universe. It is associated with cosmic rays and black holes. Because antimatter annihilates matter, it poses a threat to space travel.

    NEUTRINOS - It used to be protons, neutrons and electrons. Sub-atomic particles now proliferate: quarks, leptons, muons, gluons, photons and neutrinos. Neutrinos are like electrons but have no electrical charge. Billions of neutrinos created by fusion at the sun's core continually pass through our bodies.

    STRING THEORY - String theory came up in the 1980s. It says that long strings of matter and energy may have triggered the formation of galaxies. These strings may be defects in space-time which formed when the universe cooled.

    WORMHOLES - Wormholes are theoretical. There is no evidence that they exist. They are supposedly tunnels in space-time. Traveling through a wormhole would get us from one point to another in less time. Like a shortcut. Wormholes bring up the idea of time travel.

    MULTIVERSE - In the 21st century the multiverse theory has captured the imaginations of cosmologists. The idea is that our universe is just one of an infinite number of parallel universes, each with its own Big Bang. Some cosmologists accept that every universe has the same physical laws. Others contend that the laws of physics vary from universe to universe. Some universes are sterile. Others teem with life. If other universes exist, they are beyond our visual horizon, and the human species may be extinct before developing technology to detect them.

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  3. #2  
    Forum Bachelors Degree Kerling's Avatar
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    Why is that weird?By the way, you're missing dwarf stars. Magnetars, cosmicmagnetohydrodynamics. Etc. etc. etc.


    In the information age ignorance is a choice.
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    Forum Ph.D. merumario's Avatar
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    you should have asked for funds if you wanted to write your own encyclopedia...an incomplete one although.bravo!!!!
    "I am sorry for making this letter longer than usual.I actually lacked the time to make it shorter."###
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    RED GIANT - A red giant is a star near the end of its life. A star becomes a red giant when temperatures rise at its core, causing the star to expand. Betelgeuse, Antares and Aldebaran are red giants. Our sun will become a red giant in 5 billion years, engulfing the inner planets.

    WHITE DWARF - A white dwarf is a stellar remnant. It is small and dense. Sirius' companion, called "the pup," was the first white dwarf found. Our sun will become a white dwarf after its red giant phase. An expanding shell of gas will surround it, making it a "planetary nebula." The sun's core will cool to become a "black dwarf."
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