Through 20 years of research into the night sky, astronomers were able to map the expansion of the universe over a period of 11 billion years, using data from the Sloan Digital Survey (SDSS) project. The latest analysis of SDSS data highlights the mismatch of the Hubble constant, filling a huge gap that has long plagued astronomers — when the universe began to expand.
“Although we already know about the ancient universe and the history of recent expansion, there is still a troubling gap in the middle of 11 billion years,” said Project Researcher Kyle Dawson. Through the tireless efforts of the past five years, we are using this information to drive the most important advances in the field of cosmology in the last decade”.
It is reported that the new map uses data from different stages of the SDSS Sky Survey project to map three-dimensional images of objects at different distances from Earth to point out different time periods in the history of the universe. This map centers on the Earth, with rings of different colors representing different data sets and then spreading further afield at the latitude of space-time.
The green section of the figure highlights the closest galaxy data collected to Earth during the first two SDSS missions, with red representing large, ancient galaxies, which cover an area about 6 billion light-years with a pink circle, and blue for younger galaxies.
In further detail, quasars data from about 11 billion years ago are included. As a class of bright galaxies, its center has a fairly active supermassive black hole. The newly created map also reveals some new information to astronomers.
It is reported that researchers can use the map to measure the speed of the expansion of the universe (also known as the Hubble constant). Curiously, the team found that the current value was about 10% lower than the one calculated by measuring the distance of the adjacent galaxy.
The eBOSS 3D map of the Universal (via)
The team says the maps cite accurate data from different data sets, and their conclusions are consistent. Further research is needed as to why the Hubble constant does not match. As for the accelerated expansion of the universe, it seems to have occurred about 6 billion years ago.
It is well known that the universe is still in the process of accelerating its expansion. But in the past, astronomers have struggled to determine the speed of expansion. Previous studies have suggested that accelerated expansion began about 4 billion years ago, but new research suggests that the event node sits earlier than previously thought.
The best guess at the moment about what causes accelerated expansion is driven by “dark energy”. Finally, the study covers a considerable amount of time and control, so it can give the clearest picture of the “shape” of the universe, hopefully to calm the debate about whether it is flat or bent.