The Evolutionary Map of the Universe (EMU) Early Science Project, utilizing the Australian Square Kilometer Array Pathfinder (ASKAP) radio telescope, has made remarkable discoveries by observing a satellite galaxy of the Milky Way called the Large Magellanic Cloud. This powerful telescope has detected thousands of previously unknown radio sources, including nearby stars, supernovae, and distant galaxies. These findings could provide valuable insights into these objects' inner workings and evolution.
Scientists from Keele University described the new image produced by ASKAP as revealing thousands of radio sources that had never been seen before. Many of these sources are galaxies located millions or billions of light-years beyond the Large Magellanic Cloud. These galaxies are often detected due to supermassive black holes in their centres, emitting radio waves. However, the researchers have also identified galaxies where stars form incredibly rapidly. Scientists can study these galaxies in unprecedented detail by combining this radio data with observations from X-ray, optical, and infrared telescopes.
The Large Magellanic Cloud is a dwarf spiral galaxy that orbits the Milky Way at a distance of approximately 160,000 light-years. Its proximity makes it an ideal object for studying the structure of galaxies and the life cycle of stars. The research team used ASKAP to observe the overall structure of the Large Magellanic Cloud and individual objects within it, such as stars, supernovae, and stellar nurseries like the Tarantula Nebula, known for its intense star formation.
The team's observations included a wide range of celestial objects, from young stars to remnants of dead stars, such as expanding bubbles of material left behind after a supernova. The high resolution of ASKAP's images played a crucial role in detecting radio-emitting stars and compact nebulae in the Large Magellanic Cloud. The researchers identified diverse radio sources, from fledgling stars to planetary nebulae formed by the death of stars like the Sun.
These observations represent a significant improvement over previous radio surveys of the Large Magellanic Cloud, enabling the detection of over 50,000 radio sources. Combining the ASKAP data with other datasets, astronomers will conduct detailed analyses of planetary nebulae and supernova remnants in the future. Additionally, the radio data obtained from galaxies behind the Large Magellanic Cloud will allow for large-scale measurements of Faraday rotation and neutral atomic hydrogen. These measurements can help map the structure of galaxies and provide further insights into their characteristics.
The early observations from the EMU project using ASKAP have been promising, demonstrating the telescope's sensitivity and wide-field imaging capabilities. The discoveries so far provide a glimpse of what the full EMU survey may reveal.