Images of gas clouds that give rise to stars, except one (top, center) showing a dense cluster of ancient starsESO / VVVX survey
An enormous map of the Milky Way has been created from infrared frequencies detected by the VISTA telescope at the European Southern Observatory (ESO) in Cerro Paranal, Chile. The image contains 10 times as many objects as the previous map, published by the same group in 2012. “We can think of this work as a large census of stars, in which we are trying to understand the structure and evolution of the Milky Way,” explained Roberto Saito, an astrophysicist from the Federal University of Santa Catarina, in an interview with the podcast Pesquisa Brasil. Saito was the lead author of the article describing the research, published in the journal Astronomy & Astrophysics in September. Initially, the project planned to map an area of 560 square degrees (deg2), but in the end, the results covered 1,700 deg2. “This is the equivalent area of 8,600 full moons, triple the initial area.” This is enough space for more than 1.5 billion celestial objects. The observations taken over a decade by the study allowed scientists to see pulsating variable stars, which give a good idea of distance, one of the major difficulties faced by astronomy. This made it possible to map the three-dimensional structure of the galaxy, as well as the kinematics (the movements of the stars) over the 10-year period. One of the achievements was an improved understanding of the part of the galaxy known as the bulge. “It is shaped a bit like a box or an X, which is very different to the classic idea of a spherical galactic bulge,” Saito says, emphasizing the importance of the finding (Pesquisa Brasil, October 4).
Republish