A group of astronomers looking to better understand dark energy have started creating a three-dimensional map of the universe.
The first segment of the 3-D map is being designed to include data from 1.4 million galaxies and 160,000 quasars according to the University of Arizona, which is part of the project. The researchers hope to complete that part of the map by 2014, the university said.
The team is using a 2.5-meter telescope, equipped with two powerful special-purpose instruments, at Apache Point Observatory in New Mexico. They have so far collected astronomical data on a thousand galaxies and quasars.
Scientists have not announced how long it might take to create the whole map.
"Making a three-dimensional map is essential to understanding why the universe is expanding at an ever-accelerating rate," said University of Arizona astronomy professor Daniel Eisenstein, director of the Sloan Digital Sky Survey III. A collaboration of 350 scientists are working on the survey, also known as SDSS-III. The mapping project, known as the Baryon Oscillation Spectroscopic Survey, or BOSS, is part of SDSS-III.
Astronomers long have been trying to figure out dark energy. Experts theorise that about 70 per cent of the universe is made up of dark energy.
The universe, which is believed to be driven by the mysterious force known as dark energy, is expanding at an accelerating rate. The rapid expansion has mystified scientists.
Following the Big Bang theory, it was believed that the universe was created out of a massive explosion. It was theorised that the pull of gravity would slow the universe's rate of expansion over time, but in 1998 the Hubble Space Telescope determined that the expansion actually is speeding up, not slowing down.
According to NASA, scientists generally believe that dark energy, while its particulars are unknown, appears to be causing the universe's increasing expansion.
"We're trying to understand why that is. It's a very odd thing," said Eisenstein. "Gravity pulls things together, so you'd expect gravity would be pulling the universe back together so that it would expand at a decelerating rate. But something is causing the universe to expand at an accelerating rate. Either we misunderstand how gravity works on the largest scales, or there's some extra thing in the universe that actually causes gravity to repel structure."
Here on Earth, the Large Hadron Collider, which is the world's largest particle collider, is also looking for clues about the ingredients of dark energy and its effect on the expansion of the universe.
The BOSS team, which is made up of personnel from 42 different institutions, is focused on measuring the spectra, or colours, of galaxies and quasars. That information enables astronomers to determine how far away and how far back in time the celestial objects they're observing are.
"The data from BOSS will be the best ever obtained on the large-scale structure of the universe," said BOSS principal investigator David Schlegel of the U.S. Department of Energy's Lawrence Berkeley National Laboratory, in a statement.