A 3-dimensional interpretation of the filaments of galaxies - the largest structure known to man.
Credit: Subaru Telescope, National Astronomical Observatory of Japan
SYDNEY 31 July 2006 - Massive filaments of galaxies, stretching across an incomprehensible 200 million light-years of space have been discovered, making them the largest structure ever known to man.
The finding gives a clue into the size and structure of the universe, as well as an insight into the early days after the Big Bang.
Astronomers using the Subaru and Keck telescopes in Hawaii made the discovery while mapping an area of the sky 12 billion light-years from earth, known to harbour a large number of galaxies.
The filaments were found after researchers realised that this high concentration of galaxies was just a section of significantly larger structure. The concentration of galaxies within the filaments is more than four-times the universe's average. Previously discovered structures with such a high density have been no larger than around 50 million light years across.
Within the newly discovered galaxy filaments are large concentrations of gas, some around 10 times the size of our own Milky Way galaxy, that are probably the ancestors of the largest galaxies in existence.
Thirty-three of these gas concentrations, known as Lyman alpha blobs, have so far been spotted within the structure, the most ever discovered in the distant universe.
"Galaxies of various sizes surround us," said astronomer Yuichi Matsuda of Kyoto University, Japan. "The large gas concentrations we found may tell us a lot about how the largest of these came to be."
Formed only two billion years after the Big Bang (believed to have occurred around 13 billion years ago) the blobs reveal a glimpse of the universe in its early days.
Researchers believed the cosmos to have been quite smooth during this time and so such entities were unusual.
"Something this large and this dense would have been rare in the early universe," said astronomer Ryosuke Yamauchi from Tohoku University, Japan.
The blobs emit green light and display a diversity of shapes and brightness, with some containing several galaxies.
Telescopes have revealed that gases within the giant blobs move at speeds greater than 500 kilometres per second. The scale of the gas concentrations and the movement of the materials within them indicate their incredible size.
with the Subaru Telescope
