NASA Spitzer telescope discovers ancient galaxies from early universe days

Scientists have been able to peer back to the early days of the universe using NASA's Spitzer space telescope. The data helped them to understand how space was 13 billion years in the past and found out some of the initial galaxies.

They appear as small orange dots in the darkness of the space. The images show a host of young stars, composed mostly of helium and hydrogen. The discovery of these galaxies could help astronomers understand one of the important cosmic events called the "Epoch of Reionization."

The new research required the Spitzer telescope to stare into the same region of the sky for over 200 hours, studying the cosmos. NASA's Hubble Space Telescope also contributed data for the study.

Spitzer gathered light that had traveled across the universe to reach the Earth. The telescope received infrared signals from 135 distant galaxies, produced due to high levels of ionizing radiation.

It is considered to be an important finding because ionizing radiation is believed to have contributed to the Epoch of Reionization in the initial days of the universe.

"Our latest Spitzer result reveals how different these early galaxies are to those at later times and pinpoints our sample as a key set for providing insights into how galaxies so efficiently reionized the universe," said Garth Illingworth, a co-author on the new study.

"We did not expect that Spitzer, with a mirror no larger than a Hula-Hoop, would be capable of seeing galaxies so close to the dawn of time," said Michael Werner, a project scientist with Spitzer. "But nature is full of surprises, and the unexpected brightness of these early galaxies, together with Spitzer's superb performance, puts them within range of our small but powerful observatory."

Besides, Astronomers have managed to merge 264,000 galaxies into a single mosaic, dating back to the time just 500 million years after the big bang. NASA's Hubble Telescope data which was gathered in the last 16 years was used to chronicle the universe's evolution into a single image.