A blazar is an astronomical object within an elliptical galaxy, at whose centre there is a supermassive black hole which emits jets of radiation and particles with huge energies. When these are directed towards the Earth we can detect them. They are among the most energetic phenomena in the universo.
Magneto-hydrodynamic 3-D simulations of a relativistic jet [Credit: G. Bodo and P. Rossi (INAF-Osservatorio Astrofisico di Torino, Italy) and A. Mignone (Torino University, Italy)] |
To follow this event the researchers of the Astrophysical Observatory of Turin (OATo) coordinated an intense multifrecuency observational campaign in the framework of of the international collaboration Whole Earth Blazar Telescope (WEBT). More than 40 telescopes in the northern hemisphere took thousands of observations in the visible, radio, and near infrared ranges, which enabled the production of detailed light curves. Among the telescopoes used in the collaboration were the Carlos Sanchez Telescope and the IAC-80 and STELLA telescopes, all of them at the Teide Observatory (Izana, Tenerife).
published in Nature.
The researchers' interpretation is that the jet is "serpentine and inhomogeneous" because it emits radiation over a range of frequencies and from different zones, which change their orientation due to the instabilities in the jet, or to orbital motions.
"Three dimensional numerical simulations, taking into account the magnetohydrodynamic properties and the relativistic velocities, predict the appearance and the propagation of instabilities in the jet, which then distort it " explains Acosta. He adds that " In addition the images obtained by radio-interferometry show,on scales of one parsec (some three light years) that the jet appears to be helical, and contains many vortices. The picture which emerges is one of a twisting jet whose emission is amplified at different wavelengths at different times, by the "lighthouse effect." The orientation in December 2016 was especially favourable for the extraordinary amplification observed.
Source: Instituto de Astrofisica de Canarias (IAC) [January 30, 2018]