Colliding neutron stars, gene editing, human origins and more top stories of 2017

In science, progress rarely comes in one big shebang. Well, it has now, two years running. The first-ever direct detection of gravitational waves, our top story in 2016, launched a long-dreamed-of kind of astronomy capable of “unlocking otherwise unknowable secrets of the cosmos,” as physics writer Emily Conover puts it. 2017’s key event: a never-before-seen neutron star collision that immediately validated some theories in physics and killed others. And so a new way to probe cosmic mysteries wins our top spot again this year.

Another turning point is coming, and maybe soon, via CRISPR/Cas9, a biotechnology that holds the promise of curing genetic diseases (and the peril of making permanent, heritable tweaks). Nearly five years after the gene-editing tool debuted, researchers for the first time have used it to alter genes in viable human embryos. That’s a big advance, and worthy of the No. 2 spot.

Don’t be fooled, though. Even eureka moments like these are the fruits of the slow build of progress: Fossil by fossil, paleoanthropologists draw a picture of Homo sapiens’ earliest days. Brain by brain, the extent of damage caused by chronic traumatic encephalopathy — a disease linked to hard head knocks — becomes clear.

And crack by crack, one of the biggest icebergs ever recorded calves. That story, No. 3 on our list, is not exactly progress, but it’s surely an opportunity to make scientific headway. Teams racing to Antarctica’s Larsen C ice shelf will have an unprecedented chance to collect real-time data on how the remaining ice reacts and to reveal secrets of a long-hidden ecosystem. Building on those advances, as well as others described in our Top 10 picks, will fuel “aha!” moments — both revolutionary and incremental — well into the future. — Macon Morehouse, News Director

The Top 10 Stories of 2017

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