Infrared snapshot unveils an in-depth perspective of the Milky Way
For over a decade, scientists at the European Southern Observatory in Chile have been utilizing a distinctive telescope to capture the Milky Way, amassing over 200,000 pictures and identifying 1.5 billion celestial entities. Alongside these first infrared images, they're now sharing their findings.
This was a groundbreaking endeavor: An alliance of international astronomers employed the VISTA telescope at the European Southern Observatory in Chile to capture the Milky Way's core in infrared light over 13 years. Planets of data amounting to around 500 terabytes were amassed and over 1.5 billion objects were detected - an extensive hoard whose examination may span decades, the researchers note in "Astronomy & Astrophysics."
According to the lead researcher Roberto Saito from the University of Santa Catarina in Brazil and his team, this is the most intricate and complete map of the Milky Way's core ever created. The map reveals ten times more objects than their former discovery, published 12 years prior. VISTA, or the Visible and Infrared Telescope for Astronomy, thrives in infrared observations, enabling it to efficiently peel back the dense gas and dust veils within the Milky Way.
Infant Stars and Unexplored Star Clusters
In the 200,000 celestial images, the astronomers found unhatched infant stars enshrouded in thick dust clouds, in addition to previously unidentified star clusters - accumulations of hundreds of thousands to millions of stars. Among their numerous discoveries are also brown dwarfs - cooled-out star remnants devoid of sustained nuclear fusion - and solitary cold giant planets that traverse through empty space.
Over a span of 13 years, the researchers employed VISTA for 420 consecutive nights. They photographed each area of the surveyed celestial region, whose size equals that of 8,600 full moons, multiple times in order to track changes. In doing so, they detected a multitude of stars that exhibited regular brightness fluctuations. Certainly, some of these - referred to as Cepheids - serve astronomers as distance markers. Employing these stars, the team managed to construct a 3-dimensional map of the core Milky Way.
Stars with Hypervelocity Momentum
Moreover, by comparing various images, the astronomers also detected the movement of stars. They found numerous superspeeding stars called hypervelocity runners: stars that fly through space at velocities of up to a thousand kilometers per second. It is suspected that these stars recently approached the supermassive black hole located at the center of the Milky Way, thereby gaining their incredible speed.
Although the researchers are busily deciphering the data, they remain ambitious. The European Southern Observatory intends to upgrade VISTA with a new component, and the Extremely Large Telescope of the European Southern Observatory is also set to receive a hyper-sensitive instrument. With these telescopes, scientists will then be equipped to study the radiation of countless millions of objects in even greater detail.
This extensive data collected from VISTA could potentially lead to significant advancements in our understanding of star formation, especially in identifying and studying infant stars enshrouded in dust clouds. The comprehensive map of the Milky Way's core, achieved through education and collaboration among international astronomers, opens up new opportunities for exploration and discovery.
