Our Sun Came Late to the Milky Way's Star-Birth Party

[HubbleSite]

Our Sun missed the stellar "baby boom" that erupted in our young Milky Way galaxy 10 billion years ago. During that time the Milky Way was churning out stars 30 times faster than it does today. Our galaxy was ablaze with a firestorm of star birth as its rich reservoir of hydrogen gas compressed under gravity, creating myriad stars. But our Sun was not one of them. It was a late "boomer," arising 5 billion years later, when star birth had plunged to a trickle.

Astronomers compiled this story of our Milky Way's growth from studying galaxies similar in mass to our galaxy, found in deep surveys of the universe. Stretching back in time more than 10 billion years, the census contains nearly 2,000 snapshots of Milky Way-like galaxies. The analysis comprises the most comprehensive multi-observatory galaxy survey yet, and includes data from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), taken with NASA's Hubble Space Telescope.

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