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| Onset Of A Relativistic Jet |
Studies of journal Nature provide possibilities of cosmic accidents on August 25 2011 that has been emitting X-rays towards Earth since late march. Astronomers were first alerted of the intense and unusual high-energy flares from the new source in the constellation Draco by NASA's Swift satellite.
Professor of astronomy at Penn state university and lead scientist for the mission's X-ray telescope instrument, David Burrows says,"Incredibly, this source is still producing X-rays and may remain bright enough for Swift to observe next year." He adds,"It behaves unlike anything we've seen before." Astronomers soon realized that the source of huge-energy was because of a extraordinary event--the awakening of a distant galaxy's dormant black hole and consuming a star--known as Swift J1644+57. The galaxy is so far away that it took approximately 3.9 billion years for the to reach earth. burrows along with NASA scientist highlights X-ray and gamma ray observations from Swift and other detectors, including Japan-led-monitor of All-sky X-ray Image (MAX) instrument abroad the International Space Station.
Ashley Zauderer led the second study who is a post doctoral fellow at the Harvard-Smithsonian Center for Astrophysics in Cambridge, mass. It examines the unprecedented outburst observations from numerous ground-based radio observatories, including the National radio Astronomy Observatory's Expanded Very Large Array (EVLA) near Socorro, N.M. New studies suggest that the black hole in the galaxy hosting Swift j1644+57 may be twice the mass of the four million solar-mass black hole in the center of the MilkyWay Galaxy which itself weighs millions of times the weight of sun.
Intense tides rip apart when a star starts falling toward a black hole. The gas then swirls around the black hole, corralled as a disk, and becomes rapidly heated to temperature of millions of degrees. Rapid motion and magnetism of the innermost gas in the form of disk that spiral toward the black hole create dual, oppositely directed "funnels" through which some particles may escape. Jets driving matter at velocities greater than 90 percent the speed of light from along the black hole's spin axis. In the case of Swift J1644+57 was seen at X-rays energies and appeared so strikingly luminous.
The initial flares detected on March 28 were assumed to be a signal of a gamma-ray-burst, one of the nearly daily short blasts of high-energy radiation often associated with the death of a massive star and the birth of a black hole in the distant universe. Astronomers realized that the most plausible explanation, when they saw the emission continuing to brighten, was the tidal disruption of a sun-like star seen as beamed emission. Zauderer's team showed a brightening radio source centered on a faint galaxy near Swift's position for X-rays flares under EVLA observations by March 30.
"Our observations show that the radio-emitting region is still expanding at more than half the speed of light," said an associate professor of astrophysics at Harvard and a coauthor of radio paper, Edo Berger,"and by tracking this expansion backward in time, we can confirm that the outflow formed at the same time as the SwiftX-Ray source."
Swift, launched in November 2004, is managed by NASA's Goddard Space Flight Center in Greenbelt,Md. It is operated in collaboration with Penn state, the Los Alamos National Labrotory in N.M and the Orbital Sciences Corp., in Dulles, Va., with international collaborators in the U.K., Germany, Italy, and Japan. MAXI is operated by the Japan Aerospace Exploration Agency as an external experiment attached to the Kibo module of the space station.
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