The Swift satellite, launched by the US space agency last year, and terrestrial telescopes detected and measured the powerful explosion and its afterglow of gamma rays on September 4, charting new scientific territory.

The explosion of a massive star in the furthest reaches of the cosmos occurred at a distance of about 12.6 billion light years, said Don Lamb, an astrophysicist at the University of Chicago.

Until now, the most distant explosion recorded was 12.2 billion light years. A light year corresponds to the distance that light travels in one year, which is about 10,000 billion kilometers.

Lamb and his colleague Daniel Reichart of the University of North Carolina have anticipated since 1999 that the Swift space telescope, launched by NASA in November 2004, would break new ground by capturing the emission of gamma rays from explosions dating back to the beginning of the universe.

"We are finally starting to see the remnants of some of the oldest objects in the Universe," Reichart said.

Lamb predicted that the Swift satellite would continue to detect explosions and gamma ray emissions at even greater distances.

"It tells us when this dark matter we know indirectly exists in the universe has clamped enough and has put in enough of the ordinary matter to form stars," Lamb said at a news conference.

"So knowing when that happened in the history of the universe is extremely important for cosmologists to explain how the galaxies formed and evolved."

Gamma-ray bursts signal the death of enormous stars and the birth of black holes. The afterglow of an explosion is visible for a few days at x-ray and optical wavelengths.

Scientists measure cosmic distance by calculating redshift, the amount of light from a distant object that is shifted toward the red end of the light spectrum by the expansion of the universe.

All rights reserved. copyright 2018 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.