Studying the "heart" of a turbulent galaxy and enigmatic, with
much detail as possible, using radio telescopes of three continents, all at the same time pointing to the same celestial body. A great scientific and technological challenge which ended with a resounding success.
Driving this ambitious project of astronomical observations on a global scale, real-time Marcello was Giroletti, INAF-IRA in Bologna.
The objective of this observing campaign, which lasted from March July 2009, was an active galactic nucleus known as PMN J0948 +0022, a celestial object from the properties of all details. It is the first of a new class of active galactic nuclei issuers of high-energy gamma rays discovered in 2009 by Luigi Foschini
INAF Osservatorio Astronomico di Brera and other means of Fermi satellite. The news has created a very intriguing real "hunt" involving astronomers and telescopes around the world, tracking J0948 +0022 in different bands of radiation, from gamma rays to radio waves and X up, needed to get more scientific information on this object and image precision. And in the "window" radio is certainly one can achieve a result: an accurate map of the central region of PMN J0948 +0022 reconstructed from data collected by the network VLBI (Very Long Baseline Interferometry), which coordinates the activities of the largest radio telescopes on Earth and in which scattered is engaged, among others, the 32-meter antenna at INAF-IRA Medicine (Bo).
The level of detail achieved is impressive: only a few tens of micro-arc seconds (millionths of seconds of arc). The same keenness of vision capable of detecting a soccer ball on the surface of the Moon. "With this resolution we have sensational to reveal a super-compact and extremely bright, "says Giroletti, first author of the article published online today on Astronomy & Astrophysics Letters describing the results of this work.
"The physical mechanism that best explains these data requires the presence of a jet of matter moving at speeds close to quelledella light, which can only be achieved by extracting energy from unenorme black hole. In fact, in our image is possibiledistinguere the basis for this project. "
Observations involving instruments located in Europe and Australia, via the Far East (China and Japan), a12500 km distant from each other up, as almost the diameter of Earth. And questadistanza allowed to obtain such precise measurements, using laproprietà is increasingly becoming a resolution increasing separazionetra antennas.
And contrary to what happened so far, arrived risultatisono virtually live, using a data link infibra optical high-speed real-time allowed riversarei data generated by individual radio telescopes spread across three continents. Unavalanga of information that reached a maximum value of more than 4.2 billion bits per second, the same flow lines obtained from 600 ADSLdomestiche the maximum available bandwidth. To statoutilizzato prosecute is a supercomputer located in Holland, at the headquarters of the JIVE (Joint Institute for VLBI in Europe).
This procedure, which is now quasiprassi in Europe, had never been used before on scalaplanetaria. A pioneering experiment really, but this was funzionatoalla perfection. "The contribution of these observations dalradiotelescopio INAF / IRA of Medicine was very important. And the Italian futuroper radio astronomy is even more promising and we look forward to the return of the operational antenna NOTOC the forthcoming entry into service of the Sardinia Radio Telescope, which will enhance duestrutture also VLBI Network "sottolineaGiroletti.
Source: INAF
Marco Galliani
Office of Public Relations and Press
INAF - National Institute of Astrophysics
Viale del Parco Mellini, 84
00136 Rome
galliani@inaf.it
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