According to the National Astronomical Data Center,On January 14, Beijing time, the National Observatory's Beijing Arizona Sky Survey (bass) team and the international cooperation project team of dark energy spectral Sky Survey (DESI) jointly released the latest huge two-dimensional sky map of the universeIt paves the way for a new generation of cosmological red shift survey.
"This is the largest map of the universe we have ever measured. The sky map covers 20000 square degrees of sky, which is about half the area of the whole celestial sphere. It holds 10 trillion digital pixels and contains 2 billion objects. " David Schlegel, a project scientist from LBNL and Desi, said.
According to reports, modern astronomical observation and research found that the universe is constantly expanding, and in a state of accelerated expansion. The force that drives the expansion of the universe is called dark energy by astronomers.
Dark energy is still a mystery, it accounts for about 68% of the universe, the remaining matter is dark matter and ordinary baryonic matter. Through the spectral observation of a large number of galaxies in the universe, people can accurately obtain the retrograde velocity of galaxies, that is, the redshift, so as to obtain the distance of celestial bodies.
Redshift measurements of large-scale galaxies can accurately depict the three-dimensional distribution of cosmic matter and the influence of dark energy on the expansion of the universe.
Desi survey is a new generation of cosmological redshift survey project, which studies the growth and expansion history of cosmic structure through a large number of Galaxy redshift observations.
The project is an international cooperation project supported by the U.S. Department of energy and the U.S. natural science foundation. The leading unit is Lawrence Berkeley National Laboratory (LBNL), a subordinate unit of the U.S. Department of energy. The participating countries include China, France, Spain, the United Kingdom, Australia, Canada, Mexico, Switzerland, South Korea and Colombia.
Zhao Gongbo, a member of the desi project and deputy director of the National Astronomical Observatory, said: "desi is known as the fourth generation cosmological survey project after Sloan spectral survey. It plans to use five years to obtain the redshifts of tens of millions of galaxies and build the largest three-dimensional universe at present, which is expected to reveal the mystery of dark energy."
Nathalie palanque delabruille, cosmologist of the French Atomic and alternative energy commission and spokesman of desi, commented: "we have made great achievements in collecting and processing these data. Without these data, the desi sky survey project cannot be carried out. "