FCT researcher leads discovery of the first stars in the Universe

An international team led by astrophysicist David Sobral has discovered the brightest early universe galaxy ever found, and has shown that this galaxy appears to contain examples of the first generation of stars being formed. These discoveries confirm the long-standing theoretical prediction of the existence of these first-generation stars, which would have formed from the primordial material of the Big Bang. These huge, bright objects would have created the first elements needed to form stars like the Sun, planets and Life as we know it today.

The first stars must have formed from elements known to have existed before the existence of stars: hydrogen, helium and trace amounts of lithium. They would have been huge (several hundred or even thousands of times more massive than the Sun), extremely hot and transient, with a lifespan of just a few million years. No international search for physical evidence of their existence has been successful. Until now.

The team decided to take a different route from other researchers, mapping large areas of the sky instead of focusing on a limited, in-depth study of a small area. They used the European Southern Observatory's (ESO) Very Large Telescope (VLT), the W. M. Keck Observatory and the Subaru telescope, as well as the special NASA/ESA Hubble telescope, to observe the primordial Universe, some 800 million years after the Big Bang. Big Bang.

David Sobral, who is also a researcher at Leiden University, explains, "We knew that the risk of looking where no one is looking was easily offset by unexpected discoveries (...) It was fantastic when we discovered the CR7 galaxy, the brightest ever found in the early Universe." And the discoveries went further, "As we put the different pieces of the puzzle together, we realized that we had found something much deeper and that we were seeing, for the first time, a Holy Grail of astronomy - the first stars."

The Portuguese astrophysicist is extremely proud of his team's work, and of FCT's support, "It was only possible to make this discovery (and many others) in Portugal because of the Investigador FCT program, which I believe has the potential to help the country and universities really take advantage of FCT's support (on a par with the best funding agencies in the world). Without the Studentship given to me by the FCT in 2007 to do my PhD in Edinburgh, it would be impossible for me to be coordinating my own team today and competing with the best in the world. I would also stress the importance of Portugal being part of ESO (and ESA, for access to the Hubble Space Telescope) - without this it would be impossible to get all the time we have for discovery."

The results of the team (which includes researchers from Leiden University, the University of California and the University of Geneva) will be presented in the renowned Astrophysical Journal. They have been included by ESO in the Top 10 discoveries in astronomy made using ESO's telescopes.

Portugal at ESO - 15 years

This year marks 15 years since Portugal joined ESO. Being one of the 16 member states of the "world's largest terrestrial astronomical observatory" is recognized by researchers, funding agencies and the government as central to building and sustaining the country's small but highly productive space science community. At the public event organized by FCT on the occasion of the anniversary, Tim de Zeeuw, Director General of ESO, welcomed Portugal's good participation in ESO, in terms of the good use made of the telescopes' observation time (through competitive Calls ), the growing contribution to instrumentation and the greater involvement of national companies in ESO projects.

Paulo Garcia, Portugal's delegate to the ESO Council, reinforced these successes, reminding everyone that Portugal has a "winning agreement" with ESO. The high level of scientific impact in the area of space sciences and the capacity demonstrated by the research units in the area to attract European funding (71% compared to 35% for the other units funded by the FCT), demonstrate the positive return on Portugal's contribution of 1% to ESO's global budget.