DR. FANXIA AN How were your findings conducted?
Could you give a brief explanation of what the COSMOS field is? The COSMOS field is an astronomical survey field, located near the equator in the sky. The location made it accessible to several groundbased large telescopes in the Northern and Southern Hemispheres, as well as the major space-based telescopes. Consequently, it is one of the best-studied fields, which yielded a rich trove of astronomical data. Therefore, it is ideal for studying the properties of the galaxies in our Universe.
What is the importance of the Meerkat radio telescope? The MeerKAT radio telescope is currently the most sensitive radio telescope in the Southern Hemisphere. The MeerKAT radio is set to be surpassed by the Square Kilometre Array (SKA), which will be the world’s largest radio telescope when complete. It will have unprecedented power in reaching deeper space and forming clearer images, which will help us explore the origins of our Universe and our home galaxy — the Milky Way, to better understand our own position in the Universe.
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DVC: RESEARCH & INNOVATION MAGAZINE
We used the early science data observed by the South African MeerKAT telescope to analyse a little more than 2000 galaxies. Galaxies are a fundamental component of our Universe, and understanding how they form and evolve over cosmic time remains one of the greatest challenges of modern astronomy. We selected 2,094 galaxies that are active in forming stars, which means they are energetic and young (in cosmic time scales). This is an ideal sample for us to study the growth of the galaxies and the key features that affect their formation and evolution. The distances to these galaxies are so great that light, the fastest messenger in the Universe, takes roughly 1 to 11 giga-years (Gyr= 9 years) to arrive from them. In this way, the galaxies we observe now reflect how they used to be roughly 1 to 11 billion years ago. That means we have a collection of galaxies at different evolutionary stages. We then studied the fundamental physical properties of these distant galaxies by combining the new observations from MeerKAT and the existing observational data from other telescopes — remember that this is one of the best-covered survey fields. The MeerKAT data was collected over nearly 20 hours as part of the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) project, one of the MeerKAT’s large survey projects prioritised by the South African Radio Astronomy Observatory (SARAO). By combining the emission of light, from these galaxies, we measure how massive, how active, and how bright they appear to be at different radio frequencies, as well as other fundamental physical properties. We then connect the intensities of radio emission with the measured physical properties of these galaxies.
What was the most challenging part of your research? Combining different data from different wavelengths (optical, infra-red, and radio) is the most challenging part of our work. The angular
