Supernova ghosts found in Milky Way’s most detailed radio image
Our Milky Way galaxy contains many mysteries. One question astronomers ask themselves is, “Where are all the supernova remnants?” We may now have an answer, thanks to precise observations from a pair of radio telescopes in Australia.
In a statement on Monday, Macquarie University described the new view of the Milky Way as “the most detailed radio image yet of our galaxy.” The image – which shows the birth zones of stars and the consequences of their death – is a combination of observations from the Askap radio telescope and the Parkes radio telescope, both operated by CSIRO, Australia’s national science agency.
A supernova is a spectacular explosion marking the end of a star’s life. Astronomers have made predictions about how many supernova remnants the Milky Way should have, but we haven’t spotted as many as expected yet. The work of the radio telescope team reveals where some of these previously hidden remains are.
Radio telescopes pick up radio waves. Compare that with a telescope like Hubble, which sees mostly in visible light. Or with Webb, which uses infrared. They are different ways of “seeing” the universe.
“This new image shows a region of the Milky Way, visible only to radio telescopes, where we can see extended emission associated with hydrogen gas filling the space between dying stars, linked to the birth of new stars, and hot gas bubbles called supernova remnants,” said Macquarie University astronomer Andrew Hopkins. The full image shows the remnants of 28 supernovae. Only seven of them had already been identified.
The new image is just the start of a bigger hunt for faint supernova ghosts. “It is estimated that there could be around 1,500 more supernova remnants in the galaxy that astronomers have yet to discover,” Hopkins said. “Finding the missing remains will help us better understand our galaxy and its history.”