Galactic archaeologists are mapping the galaxy's past

With the richest vein of crystal-clear images of the galaxy to date, researchers are mapping the past orbits of stars to get closer to understanding the Milky Way's history.

What's going on: The practitioners of this science call it "galactic archaeology," which has gotten a huge boost with a burst of images from Gaia, an observatory launched into orbit by the European Space Agency in 2013 (see image above.)

Why it matters: "Astronomers, who had previously catalogued just 2.5 million of the brightest stars in the galaxy, are hailing a new era of precision astronomy," reports Quanta magazine's Natalie Wolchover.

• The observatory has tracked 1.7 billion stars with often astonishing precision. It provided the position of 14,000 asteroids and a half million quasars, galaxies that are powered by "supermassive black holes at their core."
• "For some of the brightest stars in the survey, the level of precision equates to Earth-bound observers being able to spot a Euro coin lying on the surface of the Moon," the European Space Agency said in a news release.
• The result "places us in a unique position to ... open the most exciting Galactic archaeology playground to date," researchers from the University of Strasbourg said in a paper on the Gaia data.

What's next: Walchover quotes Khyati Malhan, lead author of the paper: “The idea is to trace the streams backward in time along their orbits in order to contemplate the galaxy’s past and its formation history.”

Go deeper: 360-degree visualizations from Gaia