Astronomy

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Last year, we found a star with seven

Earth-sized planets, said goodbye to the

Cassini mission, and watched a total solar

eclipse race across America. by Liz Kruesi

Each year, Astronomy ranks the top 10 astronomical discoveries and space stories.

Choosing 2017’s top stories wasn’t easy, as it was a year full of exciting discoveries

and unexpected findings. In the end, the detection of a neutron star merger tops

the list. For the first time, astronomers spotted a pair of neutron stars spiraling

inward and colliding, throwing off gravitational waves, gamma rays, and many

other forms of light. Coming in a close second was the discovery of seven likely

terrestrial planets crammed into their star’s habitable zone. The global network of

astronomers who pinpointed the location of a weird, mysterious blast of radio waves

also makes our top 10.

Not all of the past year’s biggest space stories came from outside our solar system.

Cassini’s final goodbye after 13 years of incredible discoveries brought tears to the

eyes of the scientists who have worked with the craft, as well as those who have

followed the mission from the sidelines. And closer to home, millions watched as the

Moon blocked the Sun and its shadow raced across the continental United States.

Here’s how these and the rest of the top 10 stories stack up.