For decades, scientists have known that ordinary matter — everything made of atoms — accounts for just 15% of the universe’s matter. The rest is mysterious dark matter. But even that modest slice didn ...

Astronomers tallying up all the normal matter—stars, galaxies and gas—in the universe today have come up embarrassingly short ...

For decades, scientists have been puzzled by the missing mass in the universe. While we know that about 85% of the universe is made up of dark matter, the remaining 15% is made up of normal (baryonic) ...

A paper published in 2024 theorizes that time may have existed before the Big Bang, but we're still not entirely sure.

The finest ever map of the cosmic microwave background - the faint evidence of the universe's early form - has yielded ...

A new analysis of astronomical data suggests unknown physics is at work assisting dark energy in acting almost as ...

One of the Holy Grails in cosmology is a look back at the earliest epochs of cosmic history. Unfortunately, the universe's first few hundred thousand years are shrouded in an impenetrable fog.

Cosmic microwave background data support cosmology’s standard model but retain a mystery about the universe’s expansion rate.

Data from the Atacama Cosmology Telescope (ACT) has now given researchers new detailed images of the universe's earliest ...

The tension comes from two types of measurements. One approach looks far back in time, using the cosmic microwave background—the faint light left over from the Big Bang. The other relies on ...

The images received from this telescope are known as the cosmic microwave background, and they provide an exceptionally clear ...