TheBigBoss projectwill use500 nights of observationat the Mayall telescope, of the Arizona National Optical Astronomy Observatory (USA), with the objective ofmake the most detailed map of the skyand investigate the history of the expansion of the universe and dark energy. In the next five years this program, which has the participation of the Instituto de Astrofísica de Canarias (IAC), will determine theprecise location of 20 million galaxies and quasars, going back ten billion years to the infancy of the universe.
Looking at the sky for 500 nights with a large telescope, it is possible to develop the largest spectroscopic mapping of the universe ever made and unravel some of theenigmas of dark energy and the expansion of the universe. “BigBOSS is undoubtedly the most ambitious, solid and massive spectroscopic project on the horizon,” says IAC astronomer Ismael Pérez Fournón. Not surprisingly, the BigBOSS map will cover ten times the volume of the best map in the universe to date.
The key to the success of BigBOSS will be building aspectroscopic instrument capable of simultaneous measurements of thousands of astronomical objects. This instrument will be available to all users at the Mayall telescope, and it is hoped that the collected data can be used by astronomers around the world and the general public. The BigBOSS collaboration will now seek additional funding for the manufacture of this new instrumentation and associated software. Important contributions to the project will come from the 35 collaborating institutions, both in the United States, as well as in France, the United Kingdom, China, Spain and Korea.
Dark energy
One of the goals of BigBOSS is to examine the history of the expansion of the universe and study the nature of dark energy, a component of the cosmos about which very little is still known, and which would be responsible for the acceleration of such expansion. By measuring “baryonic acoustic oscillations,” BigBOSS “will study dark energy and may even test whether the general theory of relativity is valid,” according to the researchers.
The work is based on the study of the spectrum of light and, specifically, its“shift” or “redshift”. Measuring the redshift of light in the electromagnetic spectrum of each galaxy revealshow much the universe has expanded since the light left that galaxy. A redshift of 0.5, for example, means that the universe has expanded by 50% since the emission of the analyzed light. Comparing how the distribution of galaxies varies with the redshift at different times in the history of the universe will allow an accurate calibration of theoscillations of baryons, ordinary matter, in the early universe, and therefore the current model of the universe. These data will also constitute an unpublished source of information for the study of the evolution of galaxies, including ours.





