Vela Pulsar
Saturday, May 23, 2009
How Long Malar Rash Last?
In July 1967, caught a strange radio signal sequence. They were looking for quasars using a technique called IPS (interplanetary scintillation) in a radio telescope designed by Antony Hewish. It was the telescope that we used to, such as satellite dish. This consisted of a thousand posts about 3 m in height which held two thousand antennas (dipole) connected. The show, from 1.6 ha in size and with a couple of hundred miles of cable and wire, called Interplanetary Scintillation Array (Array IPS) and was at the Mullard Radio Astronomy Observatory at the University of Cambridge.
The IPSA explored a region of space between 50 ° and -10 ° with a periodicity of four days. The results were printed with pen on paper rolls at a rate of about 34 m per day. These records were examined manually by Jocelyn Bell Burnell, at age 23 was working on his doctoral thesis. Within a few weeks to analyze the records, Jocelyn found some signs that did not fit the typical scintillation of quasars they studied but did not seem interference. Also realized that although they disappeared and reappeared, came from the same region of space.
Jocelyn Bell in the IPS Array (1968)
According to his thesis advisor, Antony Hewish, decided to accelerate the paper to have a better discrimination of the strange signal. This could not be done continuously because it involved about 3 km of paper per day so it was sought only the right times. For weeks Jocelyn was not able to find the happy signal until one night in late November 1967, reappeared. It was a regularly spaced series of pulses.
One night before Christmas, Jocelyn began to examine other areas different in the records and found something that looked similar in the area of \u200b\u200bα-Cassiopeia. Confirmed that appeared on other days and some hours later analyzed with the telescope suspicious area for just five minutes: the pulses were clearly with periods of 1.2 seconds.
A comprehensive analysis of the records allowed to find two new sets of signals were already four. Although called LGM2, 3 and 4, the hypothesis of little green men fell apart: it was highly unlikely that four alien worlds sent at a time and at the same frequency similar signals from as far away. Had to be another cause.
From that moment and after a period of popularity, "media", Jocelyn Bell left the comments and went on to take forward his thesis on quasars, their original objective. Then he changed his place of residence and work and never returned to work on the issue that made fleetingly famous. He followed his college career and this year 2007, 64, received an honorary doctorate from the universities of Oxford and Durham.
The source of the unusual signs proved to be a hallucinogen type of star that was named pulsar (of pulsating star). Pulsars have a mass similar to that of our Sun, only a small area of \u200b\u200bfew tens of km in diameter. Are a type of neutron stars with a magnetic field more intense than Earth, about a billion times or so. The radiation is emitted at the poles of that field, not being aligned with the axis of rotation, the star becomes a cosmic lighthouse. The rotation periods of pulsars are difficult to assimilate: the LGM1, called PSR B1919 +21 then, is 1.3373 s, PSR B0531 +21 (Crab pulsar) rotates 30 times a second, PSR B1937 +21 has a period in 0.0015578 s, ie, turn 642 veces por segundo. La superficie de este púlsar se mueve a 1/7 de la velocidad de la luz.
El púlsar Vela por el observatorio de Rayos X Chandra
Es una estrella que emite radiaciones a intervalos breves y regulares, como si se tratara de un radiofaro.
Este singular comportamiento se explica admitiendo que los púlsar son estrellas de neutrones, en rápida rotación alrededor de su propio eje. http://golemp.blogspot.com/
Y así suena el pulsar Vela:
The other version
Le Noir de l'etoile III. Vela Pulsar
Grisey composed the work after meeting the astronomer and cosmologist Joe Shiloh in 1985. "... He introduced me to the sound of pulsars. I was seduced by the sounds of the Vela Pulsar and immediately asked me, like Picasso when he picked up the bike seat, 'What could I do with this?' "He explains in an introductory of the work. The answer came quickly. The composer joined the sounds of pulsars, without any manipulation, musical work, leaving it there simply as a point of reference, using the frequencies as time and developing the ideas of rotation, frequency, deceleration, acceleration and small faults seduce both astronomers. "
Le Noir de l'etoile consists of six parts, two of them devoted to the Vela Pulsar and the Pulsar 0329 +54, plus an introduction and three movements. A work that is also perfect for the Festival by the International Year of Astronomy. "Heaven is a place of noise, rhythm and violence, says of this work of Grisey French astrophysicist Jean-Pierre Luminet. Grisey's music is, in fact, as the image of the stars, sometimes rhythmic, violent, disturbing, stuttering, constantly returning to start. "
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