ScAm

April 2020, ScientificAmerican.com 33

XING

­WU ZHENG AND MARK J. REID, BAR AND SPIRAL STRUCTURE LEGACY (BESSEL) SURVEY

(A VLBA KEY SCIENCE PROJECT), NANJING UNIVERSITY, AND CENTER FOR ASTROPHYSICS |

HARVARD & SMITHSONIAN (

Milky Way chart

and

illustration

)

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