The Universe is expanding – but how fast exactly? The answer appears to depend on whether you estimate the cosmic expansion rate – referred to as the Hubble’s constant, or H0 – based on the echo of ...

Scientists have clocked the speed of Cepheid stars -- 'standard candles' that help us measure the size of the universe -- with unprecedented precision, offering exciting new insights about them.

Physicists have improved the accuracy of a technique that uses variable stars to measure distances in the universe, providing a new figure for its expansion rate. When you purchase through links on ...

Taking advantage of the presence of light echoes, a team of astronomers have used an ESO telescope to measure, at the 1% precision level, the distance of a Cepheid - a class of variable stars that ...

This Hubble Space Telescope image shows RS Puppis, one of the most luminous Cepheid variable stars. It rhythmically brightens and dims over a six-week cycle. (ASA, ESA, Hubble Heritage Team ...

Breakthroughs, discoveries, and DIY tips sent six days a week. Terms of Service and Privacy Policy. The universe is expanding—but astronomers can’t agree how fast ...

A long-running dispute about how fast our universe is expanding just became even more entrenched. New and more precise measurements of stars in the Large Magellanic Cloud, a satellite galaxy of the ...

In 1998, two teams of cosmologists observed dozens of distant supernovas and inferred that they’re racing away from Earth faster and faster all the time. This meant that—contrary to expectations—the ...

Trying to measure the size of the universe is no easy task. We know that the universe is expanding, though the exact rate of this expansion is not yet fixed. So one method that astronomers use to tell ...

Astronomers have turned up the first direct proof that “standard candles” used to illuminate the size of the universe, termed Cepheids, shrink in mass, making them not quite as standard as once ...