The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here:

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Rewriting the past and future of the universe

An astronomical image.

New international research has improved the accuracy of the parameters governing the expansion of the universe. This will help astronomers determine how the universe grew to its current state - and how it will evolve in the future. Małgorzata Bogdan, statistics professor at Lund University in Sweden, is one of the scientists behind the study.

It is well established that the universe is expanding. But with no landmarks in space, it is difficult to accurately measure how fast it is expanding. So, astronomers search for reliable landmarks. 

The same way a candle looks fainter as it gets farther away, even though the candle itself hasn’t changed, distant objects in the universe look fainter. If we know the intrinsic (initial) brightness of an object, we can calculate its distance based on its observed brightness. Objects of known brightness in the universe that allow us to calculate the distance are called “standard candles.”

An international team ushered in a new research field by leveraging the use of a variety of new statistical methods to analyze data for various standard candles such as Supernovae, Quasars (powerful black holes consuming matter in the distant universe), and Gamma Ray Bursts (sudden flashes of powerful radiation). 

Different standard candles are useful in different distant ranges, so combining multiple standard candles allowed the team to map larger areas of the universe.

The new results reduce the uncertainty of key parameters by up to 35 per cent. More accurate parameters will help determine whether the universe will continue expanding forever, or eventually fall back in on itself.

"In an era of precision cosmology, in which we strive to reduce cosmological parameters, it is important to study the distances obtained by the different objects and check that statistical assumptions are valid”, says Maria Giovanna Dainotti, Assistant Professor at the National Astronomical Observatory of Japan, who led the team of scientists.

The article in The Astrophysical Journal:
Quasars: Standard Candles up to z = 7.5 with the Precision of Supernovae Ia