Instrument aboard Hubble to probe "fossil record" of gases in early universe

Washington, September 18 : The installation of a 70 million dollar instrument on the Hubble Space Telescope in mid-October would help to probe the "fossil record" of gases in the early universe for clues to the formation and evolution of galaxies, stars and planets.

The telephone-booth-sized instrument known as the Cosmic Origins Spectrograph (COS), should help scientists better understand the "cosmic web" of material believed to permeate the universe, according to CU (University of Colorado) Boulder Professor James Green, COS science team leader.

COS will gather information from ultraviolet light emanating from distant objects, allowing scientists to look back in time and space and reconstruct the physical condition and evolution of the early universe, Green added.

"Light traveling from quasars billions of light-years away is altered as it passes through the material between galaxies, allowing us to see fingerprints of different gases," said Green of CU-Boulder's Center for Astrophysics and Space Astronomy.

"By choosing hundreds of targets in many directions, we can build up a picture of the way matter is organized in the universe on the grandest of scales," he added.

While matter is thought to have been distributed uniformly throughout space just after the Big Bang, gravity has collapsed the universe into its present structures.

"The Cosmic Origins Spectrograph is 10 times more sensitive than any instrument of its kind, which opens up a whole new vista of scientific opportunities for Hubble," said Green. "That's why we are so excited to get it into orbit," he added.

The spectrograph will break light into its individual components - similar to the way raindrops break sunlight into the colors of the rainbow - revealing information about the temperature, density, velocity, distance and chemical composition of galaxies, stars and gas clouds.

According to Green, COS will be able to peer back in time to 10 billion years ago when the first galaxies and chemical elements were forming.

The COS team will use distant quasars as "lighthouses" to track light as it passes through the cosmic web, believed to be made up of long, narrow filaments of galaxies and intergalactic gas separated by enormous voids.

"The gases in between the galaxies contain the fossil record of the first stars and galaxies," said CU-Boulder Professor Michael Shull, a co-investigator for COS and a professor in CU-Boulder's astrophysical and planetary sciences department along with Green.

"Light passing through this material in the cosmic web illuminates fingerprints of elements like carbon, oxygen, silicon and iron, the building blocks of life that were made billions of years ago inside young, hot stars," he added.

ANI