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Brian Koberlein

Who needs dark energy?

Dark energy is thought to be the driver for the expansion of the universe. But do we need dark energy to account for an expanding universe?

7 Earth-sized worlds? What we really see

A reality check from astrophysicist Brian Koberlein on what we actually see of the 7 recently discovered Earth-sized planets orbiting the star TRAPPIST-1.

What are the odds aliens exist?

The star KIC 8462852 continues to display strange behavior, baffling astronomers and prompting speculation – and these musings – about advanced aliens.

Using light to simulate time travel

Most work on time travel has focused on its theoretical aspects, but there are also attempts to simulate the effects of time travel experimentally.

Is the universe really accelerating?

New research questions the claim that the universe is accelerating. But this new work isn’t as strong as some claim.

Four quasars in a row

Astronomers at Keck Observatory in Hawaii have found a quartet of quasars, embedded in a giant nebula of cool, dense gas. The odds of four of them being so closely packed purely by chance is about 1 in 10 million.