広報室
Public Relations


Discovery of Very Distant Galaxy Candidates Near Cosmic Dawn

An international team of astronomers, including Yoshiaki Ono and Masami Ouchi at the University of Tokyo, ICRR, has conducted an ultra-deep survey with the Hubble Space Telescope, and discovered seven galaxy candidates near the so-called "cosmic dawn", when the first galaxies were born.

One of the galaxies might be the most primitive and distant galaxy ever seen. The galaxy as observed existed merely 380 million years after our universe was created 13.7 billion years ago in the Big Bang. The other six sources are also very distant galaxy candidates more than 13 billion light-years away, when the universe was just about 4 percent of its present age.

The ultra-deep survey yielded the deepest optical and near-infrared images ever taken, by combining all the exposures including the data from other Hubble programs. Analyzing the deepest images, the astronomers identified the seven faint sources as galaxy candidates at distances of more than 13 billion light years.

The new study shows that the number of galaxies in a period between 350 million and 600 million years after the Big Bang was larger than previously thought. It suggests that galaxies formed steadily, not in a sudden burst, at very early times in cosmic history.

This research will be published in the Astrophysical Journal Letters.

For more information, please refer to press releases below by Hubble Site and NASA.

>>STScI
>>NASA