Chandra reveals the jet of Sagittarius A *
It’s faint but there. The data of the observatory orbiting NASA and the Very Large Array confirmed that the jet of particles at high energies at the center of our galaxy exists. After decades of research and trial and error, scientists have found evidence.
Sagittarius A * was not very active in the last few centuries and that’s why even its jet is less visible to telescopes. Sagittarius A* (pronounced “Sagittarius A-star”, standard abbreviation Sgr A*) is a bright and very compact astronomical radio source at the center of the Milky Way Galaxy, near the border of the constellations Sagittarius and Scorpius. Sagittarius A* was discovered on February 13 and 15, 1974, by astronomers Bruce Balick and Robert Brown using the baseline interferometer of the National Radio Astronomy Observatory.
The orbiting observatory NASA’s Chandra X-ray amazes us with a new discovery. A group of researchers , also using the radio telescope, the Very Large Array (VLA) , has finally found almost certain evidence of the presence of a powerful jet coming from Sgr A * (Sagittarius A *) , the massive black hole at the center of our Milky Way (at least 4 million times more massive than the Sun). The painstaking research has gone on for decades, using also other tools, but no one until now had been able to infirm or to confirm this hypothesis.
How are these projects? Scientists believe that form when the material falls to the galactic center black hole, which rejects outside. Sagittarius A * is a black hole which is 26,000 years light from the Earth and, at least in recent centuries, it is not very active (meaning that incorporates little material) and it is for this reason that the jet is not very visible and it is weak. The study was conducted from September 1999 to March 2011, with a total of 17 days of exposure.
The jets of particles at high energies have been studied in the past and are found throughout the Universe and are produced by young stars or holes blacks even thousands of times larger than our galaxy. What are they? They carry large amounts of energy from the center of the object and govern well, in a sense, the formation of new stars in the surrounding areas. From the latest observations, the general one was that the axis of rotation of Sagittarius A * pointed in the same direction of the axis of rotation of the Milky Way. This suggests to scholars that gas and dust are constantly migrated into the black hole over the past 10 billion years.
The jet produces X-rays detected by Chandra and radio emissions; however, it was also captured by the Very Large Array . The two major tests of the existence of the jet is a straight line of X-ray emitting gas pointing towards Sagittarius A * and a shock wave seen in the Very Large Array data, where the jet seems to collide with the gas. In addition, the spectrum of Sagittarius A * is similar to that of the jets from supermassive blacks holes in other galaxies.