Universe: Discover the Milky Way’s twin

The central question in astrophysics is the formation of stars. A cold cloud of gas and dust collapses under the influence of its own gravity, increasing the pressure and temperature inside the cloud until the hydrogen it contains dissolves into helium and energy is released through this nuclear fusion. Previous observations indicated that galaxies formed stars in the early universe differently than they did in our own, which is a mystery to science.

To clarify this question, the research team looked around Nicholas Sulzinor He received his Ph.D. from the Institute of Astrophysics at the University of Vienna, Cold Molecular Gas, the Fuel for Star Formation, with radio telescopes. They used data collected from different Spanish radio telescopes. Molecular hydrogen cannot be directly observed in the radio range, but the gas can be detected by monitoring carbon monoxide.

Sulzenauer has already done the preparatory work for this project on his Master’s thesis at Co-Autor Helmut Dannerbauer Described by the Astronomical Institute of the Canary Islands. right Now at the Max Planck Institute for Radio AstronomyHe will continue to characterize cold gas in distant galaxies as part of his PhD thesis.

seahorse galaxy

Scientists have chosen a galaxy whose brightness is enhanced by a gravitational lens for an intermediate group of galaxies. This effect takes advantage of the fact that very massive cosmic objects with their own gravitational field bend the light of an object behind them, which acts as a magnifying glass. “The galaxy discovered in this way is severely distorted in shape by this effect and resembles a seahorse,” Solzinore told APA of the Astrophysical Journal Letters. study.

Mithilfe des 30-Met-Radioteleskop des Institute for Millimeter Radio Astronomy (ram) in the Sierra Nevada, they determined the distance of the “cosmic seahorse”, the nickname of the galaxy: its light has already traveled 9.6 billion years. Together with observations with another 40-meter radio telescope near Madrid, they were also able to determine the physical properties of the fuels for star formation. “The gravitational lensing effect turns the two telescopes into 300- and 400-meter-vessel instruments — which in reality would be impossible to build,” says Dannerbauer.

Cold molecular gas analysis has revealed previously unknown mechanisms of star birth at a time when star formation in the universe was at its peak. The excitation of molecular gas, which depends on the temperature and density of the gas, is similar in the seahorse galaxy to the Milky Way – so the conditions and efficiencies for star formation are very similar. “We were able to show that it is called a main-sequence galaxy with a slowly evolving star formation,” says co-author Bodo Ziegler of the University of Vienna. The Milky Way also falls into this category of galaxies.