The team of astronomers formed by Josep Martí Ribas (Universidad de Jaén), Josep M. Paredes Poy and Marta Peracaula Bosch (Universitat de Barcelona) have successfully detected the expansion of relativistic matter in the microquasar  Cygnus X-3  at 50% of the light speed. The discovery appeared in the cover page of the journal Astronomy & Astrophysics, in its August 2001 issue.

The authors of this research have discovered that Cygnus X-3 is able to eject jets of relativistic plasma at a distance far beyond than previously suspected. The jet expansion, in matter of a few weeks, can be seen with detail in the  sequence of images obtained by this group with  interferometric  techniques and using the instrument known as the VLA.

Only about a dozen of microquasars  are currently known in the Galaxy.  These astronomical objects are X-ray binary stars that behave as small scale analogs of extragalactic quasars. Their most remarkable fingerprint is their capability to accelerate and eject jets of plasma or ionized gas at relativistic velocities, i.e., comparable to the speed of light. All these phenomena take place in time scales very short in astronomical terms, hence their interest.
 

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