Gigantic elliptical galaxies, with their football shape, differ from our flat disk-like Milky Way. They are ancient galaxies which scientists have tried to understand for decades.
Now, astronomers have used new techniques to find the birth sites of these enormous systems, which offer greater insight into how they were formed.
Finding new evidence
Dr Annagrazia Puglisi, Anniversary Fellow, co-authored the research that will change what we know about the workings of the universe.
The research suggests that large flows of cold gas and collisions between disk galaxies in the early universe created these giant systems around 8 to 12 billion years ago, as the universe was rapidly evolving.
Our findings take us closer to solving a long-standing mystery in astronomy that will redefine our understanding of how galaxies were created in the early universe.
Dr Annagrazia Puglisi, Anniversary Fellow
Annagrazia explains: “Two disk galaxies smashing together can cause gas – the fuel from which stars are formed – to sink towards their centre, generating trillions of new stars.
"These galaxies form quickly – gas is sucked inwards to feed black holes and triggers bursts of stars, which are created at rates 10 to 100 times faster than our Milky Way."
Annagrazia adds that this is the first direct evidence that spheroids form through intense episodes of star formation located in the cores of distant galaxies.
International collaboration
The team included peers from around the world, such as experts from the Purple Mountain Observatory in China and the Chinese Academy of Science, among others. The study was led by Dr Qing-Hua Tan from the Purple Mountain Observatory.
Experts analysed more than 100 star-forming galaxies in the distant universe using the world’s largest radio telescope, known as ALMA, located in Chile’s Atacama desert.
Teams used a new technique which analyses the distribution of light emitted by distant and highly luminous galaxies. They then used the open-source A3COSMOS and A3GOODSS archival projects to gather high-quality observations of many distant galaxies.
This will give us a more complete picture of early galaxy formation and deepen our understanding of how the universe has evolved since the beginning of time.
Dr Annagrazia Puglisi, Anniversary Fellow
The scientists plan to combine their findings with data taken from telescopes aboard the JWST and Euclid satellites, as well as the Chinese Space Station, to map the stellar components of galaxies.
You can read more about this research in the scientific journal 'Nature'.
