Great new episode with Alex Filippenko, a University of California, Berkeley astronomer, who was part of the Nobel-winning teams that discovered dark energy in the late 1990s. Please listen.

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Nearly 25 years after its discovery, the mystery at the core of dark energy persists. Astronomers are no closer to understanding what’s behind this cosmic repulsive force that counteracts gravity and causes the cosmos to expand at an accelerating rate than when it was first discovered in 1998. Guest Alexei Filippenko is a member of the Nobel Prize-winning team that detected dark energy via supernovae surveys. He gives us the inside scoop on how dark energy was detected; what it means for our existence and the prospects for unmasking this bizarre force of nature that makes up some 70 percent of the observable universe.

Circa 2019 o.o

Scientists might be able to piece together a better understanding of the complexities around how black holes behave.

A new study shows our planet is much closer to the supermassive black hole at the galaxy’s center than previously estimated.

Scientists were expecting to find an intermediate-mass black hole at the heart of the globular cluster NGC 6397, but instead they found evidence of a concentration of smaller black holes lurking there. New data from the NASA /ESA Hubble Space Telescope have led to the first measurement of the extent of a collection of black holes in a core-collapsed globular cluster.

Globular clusters are extremely dense stellar systems, in which stars are packed closely together. They are also typically very old — the globular cluster that is the focus of this study, NGC 6397, is almost as old as the Universe itself. It resides 7800 light-years away, making it one of the closest globular clusters to Earth. Because of its very dense nucleus, it is known as a core-collapsed cluster.