Part of the Desi Telescope at the Kitt Peak National Observatory in Arizona.Credit: KPNO/Noirab/NSF/Aura/P. Marinfield
The new data has strengthened the discovery that the dark energy, the mysterious power that causes galaxies accelerating away from each other, has weakened over the past 4.5 billion years.
The impact was reported for the first time in April last year, but the recent results-which were presented on March 19 by the Dark Energy Sifting tool (DESI) at a meeting of the American Physical Association in Nahaim, California-was based on three years of receiving data, compared to one year of the results announced in 2024.
“Now I am really sitting and is the first of interest,” says Catherine Haymans, an astronomer at Edinburgh University, UK, and Astronomy Royal in Scotland.
If the results are withstanded, they can force universe scientists to review their “standard model” of the history of the universe. The model has generally assumed that dark energy is an inherent property in an empty space that does not change over time – the “cosmic constant”.
“Glove has been thrown to physicists to explain it,” he said.
Cosmic maps drawing
The Desi Telescope is located at the Kitt Peak National Observatory near Toxon, Arizona. 5,000 automatic weapons are used to direct optical fibers at specific points where galaxies or parallels are found in the field of vision. Then the fibers provide light to the sensitive spectrum that measures the amount of what each object is transformed – it means the degree that its light waves extend by expanding the space on its way to Earth. Researchers can estimate the distance of the object using its red displacement, to produce a 3D map for the date of the expansion of the universe.
On that map, the researchers then looks at the density of galaxies to determine the differences that are left from sound waves called the baron vocal fluctuations (Baos), which were present before the stars began to cost. These differences have a distinctive scale that started at 150 kilos (450,000 light years) in the primitive universe and increased with cosmic expansion; It has now grown with a factor ranging from 1000 to 150 megabyard – which makes them the largest known features in the current universe.
A slice of 3D map of galaxies based on the data collected by Desi in the first year of its wiping. Credit: Desi Collaboration/Noirab/NSF/Aura/R. Protector
By tracking the advanced size of Baos, researchers can rebuild how the expansion rate in the universe changes on EONS. About 5 billion years ago, the expansion of slowdown turned to acceleration under the pushing of dark energy. Until last year, cosmology data were compatible with the dark energy stable – which means that the universe should continue to expand at an increasing rapid rate.
But the results of the latest Desi analysis indicate that the cosmic expansion is now lower than it was in the past, which is not commensurate with the assumption that the dark energy is fixed. Instead, the data indicates that the energy density – the amount of dark energy per cubic meter of the area – is approximately 10 % less than it was 4.5 billion years ago.