A Dissident View of Relativity Theory William H. Cantrell, Ph.D. IE Editorial, Issue 59. Welcome dear colleagues to another special issue of IE Magazine. This year marks the 100th anniversary of Albert. Secure Checkout Your payment details are safe and secure. 2CO is self-certified with the U.S. Department of Commerce Safe Harbor Program. Without Any Risk If you are not 100% satisfied with your purchase, within 120 days from. Andromeda Galaxy. The Andromeda Galaxy, also known as Messier 31, M31, or NGC 224; often referred to as the Great Andromeda Nebula in older texts, is often referred to as the Great Andromeda Nebula in older texts. Andromeda is. Astronomical computations and mathematical functions source programs in C. Home page of the Cephes Mathematical Library. Magnetar - Wikipedia, the free encyclopedia. Artist's conception of a magnetar, with magnetic field lines. Artist's conception of a powerful magnetar in a star cluster. A magnetar is a type of neutron star with an extremely powerful magnetic field. The magnetic field decay powers the emission of high- energyelectromagnetic radiation, particularly X- rays and gamma rays.[1] The theory regarding these objects was proposed by Robert Duncan and Christopher Thompson in 1. March 5, 1. 97. 9.[2] During the following decade, the magnetar hypothesis has become widely accepted as a likely explanation for soft gamma repeaters (SGRs) and anomalous X- ray pulsars (AXPs). Description[edit]Like other neutron stars, magnetars are around 2. Sun. The density of the interior of a magnetar is such that a thimble full of its substance would have a mass of over 1. Magnetars are differentiated from other neutron stars by having even stronger magnetic fields, and rotating comparatively slowly, with most magnetars completing a rotation once every one to ten seconds,[3] compared to less than one second for a typical neutron star. This magnetic field gives rise to very strong and characteristic bursts of X- rays and gamma rays. The active life of a magnetar is short. Their strong magnetic fields decay after about 1. X- ray emission cease. Given the number of magnetars observable today, one estimate puts the number of inactive magnetars in the Milky Way at 3. Starquakes triggered on the surface of the magnetar disturb the magnetic field which encompasses it, often leading to extremely powerful gamma ray flare emissions which have been recorded on Earth in 1. Magnetic field[edit]Magnetars are characterized by their extremely powerful magnetic fields of 1. These magnetic fields are quadrillions of times stronger than any man- made magnet,[6] and hundreds of millions of times more powerful than the field surrounding Earth.[7] Earth has a geomagnetic field of 3. J/m. 3. A magnetar's 1. J/m. 3, with an E/c. The magnetic field of a magnetar would be lethal even at a distance of 1. At a distance of halfway from earth to the moon, a magnetar could strip information from the magnetic stripes of all credit cards on Earth.[9] As of 2. As described in the February 2. Scientific American cover story, remarkable things happen within a magnetic field of magnetar strength. X- rayphotons readily split in two or merge together. The vacuum itself is polarized, becoming strongly birefringent, like a calcite crystal. USS Lake Erie (CG-70) docked at Pearl Harbor, Hawaii in July 2004. History; United States; Name: Lake Erie: Namesake: Battle of Put-in-Bay: Awarded: 25 February 1988: Builder: Bath Iron Works: Laid down. Atoms are deformed into long cylinders thinner than the quantum- relativistic de Broglie wavelength of an electron."[2] In a field of about 1. At 1. 01. 0 teslas, a hydrogen atom becomes a spindle 2. Origins of magnetic fields[edit]The strong fields of magnetars are understood as resulting from a magnetohydrodynamic dynamo process in the turbulent, extremely dense conducting fluid that exists before the neutron star settles into its equilibrium configuration. These fields then persist due to persistent currents in a proton- superconductor phase of matter that exists at an intermediate depth within the neutron star (where neutrons predominate by mass). A similar magnetohydrodynamic dynamo process produces even more intense transient fields during coalescence of pairs of neutron stars.[1. Formation[edit]. Magnetar SGR 1. Spitzer Space Telescope. The magnetar itself is not visible at this wavelength, but it has been seen in X- ray light. When in a supernova, a star collapses to a neutron star, its magnetic field increases dramatically in strength. Halving a linear dimension increases the magnetic field fourfold. Duncan and Thompson calculated that when the spin, temperature and magnetic field of a newly formed neutron star falls into the right ranges, a dynamo mechanism could act, converting heat and rotational energy into magnetic energy and increasing the magnetic field, normally an already enormous 1. The result is a magnetar.[1. It is estimated that about one in ten supernova explosions results in a magnetar rather than a more standard neutron star or pulsar.[1. On March 5, 1. 97. Venus, the two unmanned Soviet spaceprobes, Venera 1. Solar System were hit by a blast of gamma radiation at approximately 1. EST. This contact raised the radiation readings on both the probes from a normal 1. This burst of gamma rays quickly continued to spread. Eleven seconds later, Helios 2, a NASA probe, which was in orbit around the Sun, was saturated by the blast of radiation. It soon hit Venus, and the Pioneer Venus Orbiter's detectors were overcome by the wave. Seconds later, Earth received the wave of radiation, where the powerful output of gamma rays inundated the detectors of three U. S. Department of Defense. Vela satellites, the Soviet Prognoz 7 satellite, and the Einstein Observatory. Just before the wave exited the Solar System, the blast also hit the International Sun–Earth Explorer. This extremely powerful blast of gamma radiation constituted the strongest wave of extra- solar gamma rays ever detected; it was over 1. Because gamma rays travel at the speed of light and the time of the pulse was recorded by several distant spacecraft as well as on Earth, the source of the gamma radiation could be calculated to an accuracy of about 2 arcseconds.[1. The direction of the source corresponded with the remnants of a star that had gone supernova around 3. B. C. E.[4] It was in the Large Magellanic Cloud and the source was named SGR 0. GRB 7. 90. 30. 5b, the first observed SGR megaflare. Recent discoveries[edit]. Artist's impression of a gamma- ray burst and supernova powered by a magnetar.[1. On February 2. 1, 2. NASA and researchers at Mc. Gill University had discovered a neutron star with the properties of a radio pulsar which emitted some magnetically powered bursts, like a magnetar. This suggests that magnetars are not merely a rare type of pulsar but may be a (possibly reversible) phase in the lives of some pulsars.[1. On September 2. 4, 2. ESO announced what it ascertained was the first optically active magnetar- candidate yet discovered, using ESO's Very Large Telescope. The newly discovered object was designated SWIFT J1. On September 1, 2. ESA released news of a magnetar close to supernova remnant Kesteven 7. Astronomers from Europe and China discovered this magnetar, named 3. XMM J1. 85. 24. 6. In 2. 01. 3, a magnetar PSR J1. Sagittarius A* system. This object provides a valuable tool for studying the ionized interstellar medium toward the Galactic Center. Known magnetars[edit]. On 2. 7 December 2. SGR 1. 80. 6- 2. 0 passed through the Solar System (artist's conception shown). The burst was so powerful that it had effects on Earth's atmosphere, at a range of about 5. As of November 2. A full listing is given in the Mc. Gill SGR/AXP Online Catalog.[5] Examples of known magnetars include: SGR 0. Large Magellanic Cloud, the first found (in 1. SGR 1. 80. 6- 2. 0, located 5. Earth on the far side of the Milky Way in the constellation of Sagittarius. SGR 1. 90. 0+1. 4, located 2. Aquila. After a long period of low emissions (significant bursts only in 1. May–August 1. 99. August 2. 7, 1. 99. NEAR Shoemaker to shut down to prevent damage and to saturate instruments on Beppo. SAX, WIND and RXTE. On May 2. 9, 2. 00. NASA's Spitzer telescope discovered a ring of matter around this magnetar. It is thought that this ring formed in the 1. SGR 0. 50. 1+4. 51. August 2. 00. 8.[2. E 1. 04. 8. 1−5. Carina. The original star, from which the magnetar formed, had a mass 3. Sun. As of September 2. ESO reports identification of an object which it has initially identified as a magnetar, SWIFT J1. GRB 0. 70. 61. 0).[1. CXO J1. 64. 71. 0. Westerlund 1, which formed from a star with a mass in excess of 4. SWIFT J1. 82. 2. 3 Star- 1. July 2. 01. 1 by Italian and Spanish researchers of CSIC at Madrid and Catalonia. This magnetar contrary to previsions has a low external magnetic field, and it might be as young as half a million years.[2. XMM J1. 85. 24. 6. Discovered by international team of astronomers, looking at data from ESA's XMM- Newton X- raytelescope. Bright supernovae[edit]A recent progress in theory suggests that the energy deposition from these magnetars into the expanding supernova remnant could possibly explain some observed cases of unusually bright supernovae. Traditionally such bright events are thought to come from very large stars when they become pair- instability supernova (or pulsational pair- instability supernova). However, two papers[2. University of California, Berkeley, University of California, Santa Cruz and University of California, Santa Barbara provided semi- analytical and numerical models to explain some of the brightest events ever seen, such as SN 2. SN 2. 00. 8es. A research led by Matt Nicholl, of the Astrophysics Research Centre at Queen's School of Mathematics and Physics of Queen's University Belfast, the results of which were published on October 1. Nature, has explained the newly discovered luminous transient PTF 1. See also[edit]References[edit]Specific^ ab. Ward; Brown lee, p. Kouveliotou, C.; Duncan, R. C.; Thompson, C. (February 2. Magnetars Magnetars". Scientific American; Page 3. Magnetars, Soft Gamma Repeaters and Very Strong Magnetic Fields". Robert C. Duncan, University of Texas at Austin. March 2. 00. 3. Retrieved 2. Kouveliotou, C.; Duncan, R. C.; Thompson, C. (February 2. Magnetars". Scientific American; Page 3. Mc. Gill SGR/AXP Online Catalog". Retrieved 2 Jan 2. HLD user program, at Dresden High Magnetic Field Laboratory". Retrieved 2. 00. 9- 0. Naeye, Robert (February 1. The Brightest Blast". Sky & Telescope. Retrieved 1. 7 December 2. Duncan, Robert. "`MAGNETARS', SOFT GAMMA REPEATERS & VERY STRONG MAGNETIC FIELDS". University of Texas. Archived from the original on May 1. Retrieved 2. 01. 3- 0. Wanjek, Christopher (February 1. Cosmic Explosion Among the Brightest in Recorded History". NASA. Retrieved 1. December 2. 00. 7. ^Dooling, Dave (May 2. Magnetar" discovery solves 1. Science@NASA Headline News. Retrieved 1. 7 December 2.
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