A new discovery made by astronomers at the Atacama Large Millimeter/submmillimeter Array (ALMA) telescope in Chile has revealed signs of a “hot spot” (gas bubble) revolving around Sagittarius A*, black hole at the center of the Milky Way.
According to study lead author Maciek Velthus of the Max Planck Institute for Radio Astronomy in Bonn, Germany: around Sagittarius A* in an orbit similar in size to that of the planet Mercury, but makes a complete revolution in about 70 minutes.“
But for this observation to be correct, the Polish astrophysicist explains, “the rate at which [o ponto quente] if it moves, it must be huge, about 30% of the speed of light“. The observations were carried out as part of the international collaboration Event Horizon Telescope (EHT), a “black hole hunter” project that brings together the largest telescopes in the world.
How did Atacama astronomers discover the “hot spot”?
It was during one of these global radio telescope connections in April 2017 that Vilgus and colleagues were able to compare their ALMA data with other Sagittarius A* EHT observations. To his surprise, his research based on radio emission polarized black hole turned out to be stronger.
Coincidentally, some of the observations were made just after the burst of X-ray energy emitted from the center of the Milky Way and detected by NASA’s Chandra Space Telescope. The novelty, Vigas explains, is that this type of explosion, previously limited to X-ray and infrared observations of Sagittarius*, showed that “hot spots in orbit are also present in radio observations”like ALMA.
At the same time, the team expects that in the future it will be possible to observe these gas accumulations together with EHT partners, until “one day we feel free to say we ‘know’ what’s going on in Sagittarius A*,” concludes Vilgus.
ARTICLE – Astronomy and astrophysics – DOI: 10.1051/0004-6361/202244493.
